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4.9.126-intel-pk-standard Kernel bug #5

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dv01d opened this issue Oct 3, 2018 · 3 comments
Open

4.9.126-intel-pk-standard Kernel bug #5

dv01d opened this issue Oct 3, 2018 · 3 comments

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@dv01d
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dv01d commented Oct 3, 2018

Not certain how you want these, but I keep having this kernel error pop up on every boot. Using an Up2 board with NV4200. Primarily using default kernel options from meta-intel and meta-up-board, with a just a few extra kernel modules compiled in.

------------[ cut here ]------------
[ 9.027445] WARNING: CPU: 1 PID: 222 at /home/build/yocto/build/tmp/work-shared/up-board/kernel-source/fs/sysfs/dir.c:31 sysfs_warn_dup+0x62/0x80
[ 9.027446] sysfs: cannot create duplicate filename '/bus/platform/devices/intel_usb_dr_phy.0'
[ 9.027470] Modules linked in: snd_soc_skl(+) sdw_cnl snd_soc_skl_ipc sdw_bus crc8 snd_soc_sst_ipc snd_soc_sst_dsp snd_hda_ext_core snd_soc_sst_match snd_soc_core pinctrl_upboard intel_rapl x86_pkg_temp_thermal efivars leds_upboard iwlmvm mac80211 coretemp btusb btrtl btbcm snd_compress iwlwifi btintel cfg80211 spi_pxa2xx_platform ac97_bus bluetooth pwm_lpss_pci(+) pwm_lpss mei_me(+) mei dwc3_pci(+) upboard_fpga i915 video
[ 9.027473] CPU: 1 PID: 222 Comm: systemd-udevd Not tainted 4.9.126-intel-pk-standard #1
[ 9.027474] Hardware name: AAEON UP-APL01/UP-APL01, BIOS UPA1AM33 01/17/2018
[ 9.027478] ffffc900007fb6c8 ffffffff81409ef9 ffffffff81be1ad0 ffffc900007fb718
[ 9.027480] ffffc900007fb708 ffffffff8114c96c 00000009752a2000 ffff8801752a2000
[ 9.027482] ffff8801762b14e0 ffff88017b208d98 0000000000000001 ffffffffffffffef
[ 9.027483] Call Trace:
[ 9.027489] [] dump_stack+0x4d/0x64
[ 9.027493] [] __warn.cold.10+0x93/0xb8
[ 9.027497] [] warn_slowpath_fmt+0x4f/0x60
[ 9.027499] [] ? kernfs_path_from_node+0x4f/0x60
[ 9.027501] [] sysfs_warn_dup+0x62/0x80
[ 9.027503] [] sysfs_do_create_link_sd.isra.2+0xbe/0xd0
[ 9.027505] [] sysfs_create_link+0x25/0x40
[ 9.027509] [] bus_add_device+0x122/0x1d0
[ 9.027512] [] device_add+0x2d5/0x5d0
[ 9.027514] [] platform_device_add+0x10c/0x220
[ 9.027520] [] dwc3_pci_quirks+0x33c/0x390 [dwc3_pci]
[ 9.027523] [] ? mp_map_gsi_to_irq+0xa0/0xc0
[ 9.027526] [] ? acpi_register_gsi_ioapic+0x84/0x140
[ 9.027529] [] ? pci_conf1_read+0xa9/0x100
[ 9.027532] [] ? __kmalloc_track_caller+0x101/0x200
[ 9.027535] [] ? complete_all+0x42/0x50
[ 9.027537] [] ? platform_device_add_resources+0x2c/0x70
[ 9.027540] [] dwc3_pci_probe+0x13f/0x1fa [dwc3_pci]
[ 9.027543] [] pci_device_probe+0x95/0x100
[ 9.027545] [] driver_probe_device+0x1ae/0x280
[ 9.027547] [] __driver_attach+0x99/0xb0
[ 9.027549] [] ? driver_probe_device+0x280/0x280
[ 9.027550] [] bus_for_each_dev+0x70/0xa0
[ 9.027552] [] driver_attach+0x1e/0x20
[ 9.027553] [] bus_add_driver+0x1a1/0x1e0
[ 9.027555] [] ? 0xffffffffa02de000
[ 9.027556] [] driver_register+0x70/0xc0
[ 9.027558] [] ? 0xffffffffa02de000
[ 9.027559] [] __pci_register_driver+0x49/0x50
[ 9.027562] [] dwc3_pci_driver_init+0x1e/0x20 [dwc3_pci]
[ 9.027564] [] do_one_initcall+0x3d/0xf0
[ 9.027565] [] ? kfree+0x172/0x190
[ 9.027567] [] ? kmem_cache_alloc_trace+0xbc/0x1a0
[ 9.027570] [] do_init_module+0x60/0x1d0
[ 9.027571] [] load_module+0x1d34/0x21b0
[ 9.027573] [] ? __symbol_put+0x60/0x60
[ 9.027576] [] ? kernel_read_file+0x1a1/0x1d0
[ 9.027578] [] SYSC_finit_module+0xa8/0xc0
[ 9.027580] [] SyS_finit_module+0xe/0x10
[ 9.027582] [] do_syscall_64+0x61/0xc0
[ 9.027586] [] entry_SYSCALL_64_after_swapgs+0x58/0xc6
[ 9.027588] ---[ end trace 9573789947157798 ]---

sys-oak pushed a commit that referenced this issue Oct 3, 2018
[ Upstream commit 46b3722 ]

We occasionaly hit following assert failure in 'perf top', when processing the
/proc info in multiple threads.

  perf: ...include/linux/refcount.h:109: refcount_inc:
        Assertion `!(!refcount_inc_not_zero(r))' failed.

The gdb backtrace looks like this:

  [Switching to Thread 0x7ffff11ba700 (LWP 13749)]
  0x00007ffff50839fb in raise () from /lib64/libc.so.6
  (gdb)
  #0  0x00007ffff50839fb in raise () from /lib64/libc.so.6
  #1  0x00007ffff5085800 in abort () from /lib64/libc.so.6
  #2  0x00007ffff507c0da in __assert_fail_base () from /lib64/libc.so.6
  #3  0x00007ffff507c152 in __assert_fail () from /lib64/libc.so.6
  #4  0x0000000000535373 in refcount_inc (r=0x7fffdc009be0)
      at ...include/linux/refcount.h:109
  #5  0x00000000005354f1 in comm_str__get (cs=0x7fffdc009bc0)
      at util/comm.c:24
  #6  0x00000000005356bd in __comm_str__findnew (str=0x7fffd000b260 ":2",
      root=0xbed5c0 <comm_str_root>) at util/comm.c:72
  #7  0x000000000053579e in comm_str__findnew (str=0x7fffd000b260 ":2",
      root=0xbed5c0 <comm_str_root>) at util/comm.c:95
  #8  0x000000000053582e in comm__new (str=0x7fffd000b260 ":2",
      timestamp=0, exec=false) at util/comm.c:111
  #9  0x00000000005363bc in thread__new (pid=2, tid=2) at util/thread.c:57
  #10 0x0000000000523da0 in ____machine__findnew_thread (machine=0xbfde38,
      threads=0xbfdf28, pid=2, tid=2, create=true) at util/machine.c:457
  #11 0x0000000000523eb4 in __machine__findnew_thread (machine=0xbfde38,
  ...

The failing assertion is this one:

  REFCOUNT_WARN(!refcount_inc_not_zero(r), ...

The problem is that we keep global comm_str_root list, which
is accessed by multiple threads during the 'perf top' startup
and following 2 paths can race:

  thread 1:
    ...
    thread__new
      comm__new
        comm_str__findnew
          down_write(&comm_str_lock);
          __comm_str__findnew
            comm_str__get

  thread 2:
    ...
    comm__override or comm__free
      comm_str__put
        refcount_dec_and_test
          down_write(&comm_str_lock);
          rb_erase(&cs->rb_node, &comm_str_root);

Because thread 2 first decrements the refcnt and only after then it removes the
struct comm_str from the list, the thread 1 can find this object on the list
with refcnt equls to 0 and hit the assert.

This patch fixes the thread 1 __comm_str__findnew path, by ignoring objects
that already dropped the refcnt to 0. For the rest of the objects we take the
refcnt before comparing its name and release it afterwards with comm_str__put,
which can also release the object completely.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Lukasz Odzioba <lukasz.odzioba@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wang Nan <wangnan0@huawei.com>
Cc: kernel-team@lge.com
Link: http://lkml.kernel.org/r/20180720101740.GA27176@krava
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Oct 3, 2018
commit 3e1a127 upstream.

When we disable hotplugging on the GPU, we need to be able to
synchronize with each connector's hotplug interrupt handler before the
interrupt is finally disabled. This can be a problem however, since
nouveau_connector_detect() currently grabs a runtime power reference
when handling connector probing. This will deadlock the runtime suspend
handler like so:

[  861.480896] INFO: task kworker/0:2:61 blocked for more than 120 seconds.
[  861.483290]       Tainted: G           O      4.18.0-rc6Lyude-Test+ #1
[  861.485158] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  861.486332] kworker/0:2     D    0    61      2 0x80000000
[  861.487044] Workqueue: events nouveau_display_hpd_work [nouveau]
[  861.487737] Call Trace:
[  861.488394]  __schedule+0x322/0xaf0
[  861.489070]  schedule+0x33/0x90
[  861.489744]  rpm_resume+0x19c/0x850
[  861.490392]  ? finish_wait+0x90/0x90
[  861.491068]  __pm_runtime_resume+0x4e/0x90
[  861.491753]  nouveau_display_hpd_work+0x22/0x60 [nouveau]
[  861.492416]  process_one_work+0x231/0x620
[  861.493068]  worker_thread+0x44/0x3a0
[  861.493722]  kthread+0x12b/0x150
[  861.494342]  ? wq_pool_ids_show+0x140/0x140
[  861.494991]  ? kthread_create_worker_on_cpu+0x70/0x70
[  861.495648]  ret_from_fork+0x3a/0x50
[  861.496304] INFO: task kworker/6:2:320 blocked for more than 120 seconds.
[  861.496968]       Tainted: G           O      4.18.0-rc6Lyude-Test+ #1
[  861.497654] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  861.498341] kworker/6:2     D    0   320      2 0x80000080
[  861.499045] Workqueue: pm pm_runtime_work
[  861.499739] Call Trace:
[  861.500428]  __schedule+0x322/0xaf0
[  861.501134]  ? wait_for_completion+0x104/0x190
[  861.501851]  schedule+0x33/0x90
[  861.502564]  schedule_timeout+0x3a5/0x590
[  861.503284]  ? mark_held_locks+0x58/0x80
[  861.503988]  ? _raw_spin_unlock_irq+0x2c/0x40
[  861.504710]  ? wait_for_completion+0x104/0x190
[  861.505417]  ? trace_hardirqs_on_caller+0xf4/0x190
[  861.506136]  ? wait_for_completion+0x104/0x190
[  861.506845]  wait_for_completion+0x12c/0x190
[  861.507555]  ? wake_up_q+0x80/0x80
[  861.508268]  flush_work+0x1c9/0x280
[  861.508990]  ? flush_workqueue_prep_pwqs+0x1b0/0x1b0
[  861.509735]  nvif_notify_put+0xb1/0xc0 [nouveau]
[  861.510482]  nouveau_display_fini+0xbd/0x170 [nouveau]
[  861.511241]  nouveau_display_suspend+0x67/0x120 [nouveau]
[  861.511969]  nouveau_do_suspend+0x5e/0x2d0 [nouveau]
[  861.512715]  nouveau_pmops_runtime_suspend+0x47/0xb0 [nouveau]
[  861.513435]  pci_pm_runtime_suspend+0x6b/0x180
[  861.514165]  ? pci_has_legacy_pm_support+0x70/0x70
[  861.514897]  __rpm_callback+0x7a/0x1d0
[  861.515618]  ? pci_has_legacy_pm_support+0x70/0x70
[  861.516313]  rpm_callback+0x24/0x80
[  861.517027]  ? pci_has_legacy_pm_support+0x70/0x70
[  861.517741]  rpm_suspend+0x142/0x6b0
[  861.518449]  pm_runtime_work+0x97/0xc0
[  861.519144]  process_one_work+0x231/0x620
[  861.519831]  worker_thread+0x44/0x3a0
[  861.520522]  kthread+0x12b/0x150
[  861.521220]  ? wq_pool_ids_show+0x140/0x140
[  861.521925]  ? kthread_create_worker_on_cpu+0x70/0x70
[  861.522622]  ret_from_fork+0x3a/0x50
[  861.523299] INFO: task kworker/6:0:1329 blocked for more than 120 seconds.
[  861.523977]       Tainted: G           O      4.18.0-rc6Lyude-Test+ #1
[  861.524644] "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
[  861.525349] kworker/6:0     D    0  1329      2 0x80000000
[  861.526073] Workqueue: events nvif_notify_work [nouveau]
[  861.526751] Call Trace:
[  861.527411]  __schedule+0x322/0xaf0
[  861.528089]  schedule+0x33/0x90
[  861.528758]  rpm_resume+0x19c/0x850
[  861.529399]  ? finish_wait+0x90/0x90
[  861.530073]  __pm_runtime_resume+0x4e/0x90
[  861.530798]  nouveau_connector_detect+0x7e/0x510 [nouveau]
[  861.531459]  ? ww_mutex_lock+0x47/0x80
[  861.532097]  ? ww_mutex_lock+0x47/0x80
[  861.532819]  ? drm_modeset_lock+0x88/0x130 [drm]
[  861.533481]  drm_helper_probe_detect_ctx+0xa0/0x100 [drm_kms_helper]
[  861.534127]  drm_helper_hpd_irq_event+0xa4/0x120 [drm_kms_helper]
[  861.534940]  nouveau_connector_hotplug+0x98/0x120 [nouveau]
[  861.535556]  nvif_notify_work+0x2d/0xb0 [nouveau]
[  861.536221]  process_one_work+0x231/0x620
[  861.536994]  worker_thread+0x44/0x3a0
[  861.537757]  kthread+0x12b/0x150
[  861.538463]  ? wq_pool_ids_show+0x140/0x140
[  861.539102]  ? kthread_create_worker_on_cpu+0x70/0x70
[  861.539815]  ret_from_fork+0x3a/0x50
[  861.540521]
               Showing all locks held in the system:
[  861.541696] 2 locks held by kworker/0:2/61:
[  861.542406]  #0: 000000002dbf8af5 ((wq_completion)"events"){+.+.}, at: process_one_work+0x1b3/0x620
[  861.543071]  #1: 0000000076868126 ((work_completion)(&drm->hpd_work)){+.+.}, at: process_one_work+0x1b3/0x620
[  861.543814] 1 lock held by khungtaskd/64:
[  861.544535]  #0: 0000000059db4b53 (rcu_read_lock){....}, at: debug_show_all_locks+0x23/0x185
[  861.545160] 3 locks held by kworker/6:2/320:
[  861.545896]  #0: 00000000d9e1bc59 ((wq_completion)"pm"){+.+.}, at: process_one_work+0x1b3/0x620
[  861.546702]  #1: 00000000c9f92d84 ((work_completion)(&dev->power.work)){+.+.}, at: process_one_work+0x1b3/0x620
[  861.547443]  #2: 000000004afc5de1 (drm_connector_list_iter){.+.+}, at: nouveau_display_fini+0x96/0x170 [nouveau]
[  861.548146] 1 lock held by dmesg/983:
[  861.548889] 2 locks held by zsh/1250:
[  861.549605]  #0: 00000000348e3cf6 (&tty->ldisc_sem){++++}, at: ldsem_down_read+0x37/0x40
[  861.550393]  #1: 000000007009a7a8 (&ldata->atomic_read_lock){+.+.}, at: n_tty_read+0xc1/0x870
[  861.551122] 6 locks held by kworker/6:0/1329:
[  861.551957]  #0: 000000002dbf8af5 ((wq_completion)"events"){+.+.}, at: process_one_work+0x1b3/0x620
[  861.552765]  #1: 00000000ddb499ad ((work_completion)(&notify->work)#2){+.+.}, at: process_one_work+0x1b3/0x620
[  861.553582]  #2: 000000006e013cbe (&dev->mode_config.mutex){+.+.}, at: drm_helper_hpd_irq_event+0x6c/0x120 [drm_kms_helper]
[  861.554357]  #3: 000000004afc5de1 (drm_connector_list_iter){.+.+}, at: drm_helper_hpd_irq_event+0x78/0x120 [drm_kms_helper]
[  861.555227]  #4: 0000000044f294d9 (crtc_ww_class_acquire){+.+.}, at: drm_helper_probe_detect_ctx+0x3d/0x100 [drm_kms_helper]
[  861.556133]  #5: 00000000db193642 (crtc_ww_class_mutex){+.+.}, at: drm_modeset_lock+0x4b/0x130 [drm]

[  861.557864] =============================================

[  861.559507] NMI backtrace for cpu 2
[  861.560363] CPU: 2 PID: 64 Comm: khungtaskd Tainted: G           O      4.18.0-rc6Lyude-Test+ #1
[  861.561197] Hardware name: LENOVO 20EQS64N0B/20EQS64N0B, BIOS N1EET78W (1.51 ) 05/18/2018
[  861.561948] Call Trace:
[  861.562757]  dump_stack+0x8e/0xd3
[  861.563516]  nmi_cpu_backtrace.cold.3+0x14/0x5a
[  861.564269]  ? lapic_can_unplug_cpu.cold.27+0x42/0x42
[  861.565029]  nmi_trigger_cpumask_backtrace+0xa1/0xae
[  861.565789]  arch_trigger_cpumask_backtrace+0x19/0x20
[  861.566558]  watchdog+0x316/0x580
[  861.567355]  kthread+0x12b/0x150
[  861.568114]  ? reset_hung_task_detector+0x20/0x20
[  861.568863]  ? kthread_create_worker_on_cpu+0x70/0x70
[  861.569598]  ret_from_fork+0x3a/0x50
[  861.570370] Sending NMI from CPU 2 to CPUs 0-1,3-7:
[  861.571426] NMI backtrace for cpu 6 skipped: idling at intel_idle+0x7f/0x120
[  861.571429] NMI backtrace for cpu 7 skipped: idling at intel_idle+0x7f/0x120
[  861.571432] NMI backtrace for cpu 3 skipped: idling at intel_idle+0x7f/0x120
[  861.571464] NMI backtrace for cpu 5 skipped: idling at intel_idle+0x7f/0x120
[  861.571467] NMI backtrace for cpu 0 skipped: idling at intel_idle+0x7f/0x120
[  861.571469] NMI backtrace for cpu 4 skipped: idling at intel_idle+0x7f/0x120
[  861.571472] NMI backtrace for cpu 1 skipped: idling at intel_idle+0x7f/0x120
[  861.572428] Kernel panic - not syncing: hung_task: blocked tasks

So: fix this by making it so that normal hotplug handling /only/ happens
so long as the GPU is currently awake without any pending runtime PM
requests. In the event that a hotplug occurs while the device is
suspending or resuming, we can simply defer our response until the GPU
is fully runtime resumed again.

Changes since v4:
- Use a new trick I came up with using pm_runtime_get() instead of the
  hackish junk we had before

Signed-off-by: Lyude Paul <lyude@redhat.com>
Reviewed-by: Karol Herbst <kherbst@redhat.com>
Acked-by: Daniel Vetter <daniel@ffwll.ch>
Cc: stable@vger.kernel.org
Cc: Lukas Wunner <lukas@wunner.de>
Signed-off-by: Ben Skeggs <bskeggs@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Oct 3, 2018
commit a5ba1d9 upstream.

We have reports of the following crash:

    PID: 7 TASK: ffff88085c6d61c0 CPU: 1 COMMAND: "kworker/u25:0"
    #0 [ffff88085c6db710] machine_kexec at ffffffff81046239
    #1 [ffff88085c6db760] crash_kexec at ffffffff810fc248
    #2 [ffff88085c6db830] oops_end at ffffffff81008ae7
    #3 [ffff88085c6db860] no_context at ffffffff81050b8f
    #4 [ffff88085c6db8b0] __bad_area_nosemaphore at ffffffff81050d75
    #5 [ffff88085c6db900] bad_area_nosemaphore at ffffffff81050e83
    #6 [ffff88085c6db910] __do_page_fault at ffffffff8105132e
    #7 [ffff88085c6db9b0] do_page_fault at ffffffff8105152c
    #8 [ffff88085c6db9c0] page_fault at ffffffff81a3f122
    [exception RIP: uart_put_char+149]
    RIP: ffffffff814b67b5 RSP: ffff88085c6dba78 RFLAGS: 00010006
    RAX: 0000000000000292 RBX: ffffffff827c5120 RCX: 0000000000000081
    RDX: 0000000000000000 RSI: 000000000000005f RDI: ffffffff827c5120
    RBP: ffff88085c6dba98 R8: 000000000000012c R9: ffffffff822ea320
    R10: ffff88085fe4db04 R11: 0000000000000001 R12: ffff881059f9c000
    R13: 0000000000000001 R14: 000000000000005f R15: 0000000000000fba
    ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018
    #9 [ffff88085c6dbaa0] tty_put_char at ffffffff81497544
    #10 [ffff88085c6dbac0] do_output_char at ffffffff8149c91c
    #11 [ffff88085c6dbae0] __process_echoes at ffffffff8149cb8b
    #12 [ffff88085c6dbb30] commit_echoes at ffffffff8149cdc2
    #13 [ffff88085c6dbb60] n_tty_receive_buf_fast at ffffffff8149e49b
    #14 [ffff88085c6dbbc0] __receive_buf at ffffffff8149ef5a
    #15 [ffff88085c6dbc20] n_tty_receive_buf_common at ffffffff8149f016
    #16 [ffff88085c6dbca0] n_tty_receive_buf2 at ffffffff8149f194
    #17 [ffff88085c6dbcb0] flush_to_ldisc at ffffffff814a238a
    #18 [ffff88085c6dbd50] process_one_work at ffffffff81090be2
    #19 [ffff88085c6dbe20] worker_thread at ffffffff81091b4d
    #20 [ffff88085c6dbeb0] kthread at ffffffff81096384
    #21 [ffff88085c6dbf50] ret_from_fork at ffffffff81a3d69f​

after slogging through some dissasembly:

ffffffff814b6720 <uart_put_char>:
ffffffff814b6720:	55                   	push   %rbp
ffffffff814b6721:	48 89 e5             	mov    %rsp,%rbp
ffffffff814b6724:	48 83 ec 20          	sub    $0x20,%rsp
ffffffff814b6728:	48 89 1c 24          	mov    %rbx,(%rsp)
ffffffff814b672c:	4c 89 64 24 08       	mov    %r12,0x8(%rsp)
ffffffff814b6731:	4c 89 6c 24 10       	mov    %r13,0x10(%rsp)
ffffffff814b6736:	4c 89 74 24 18       	mov    %r14,0x18(%rsp)
ffffffff814b673b:	e8 b0 8e 58 00       	callq  ffffffff81a3f5f0 <mcount>
ffffffff814b6740:	4c 8b a7 88 02 00 00 	mov    0x288(%rdi),%r12
ffffffff814b6747:	45 31 ed             	xor    %r13d,%r13d
ffffffff814b674a:	41 89 f6             	mov    %esi,%r14d
ffffffff814b674d:	49 83 bc 24 70 01 00 	cmpq   $0x0,0x170(%r12)
ffffffff814b6754:	00 00
ffffffff814b6756:	49 8b 9c 24 80 01 00 	mov    0x180(%r12),%rbx
ffffffff814b675d:	00
ffffffff814b675e:	74 2f                	je     ffffffff814b678f <uart_put_char+0x6f>
ffffffff814b6760:	48 89 df             	mov    %rbx,%rdi
ffffffff814b6763:	e8 a8 67 58 00       	callq  ffffffff81a3cf10 <_raw_spin_lock_irqsave>
ffffffff814b6768:	41 8b 8c 24 78 01 00 	mov    0x178(%r12),%ecx
ffffffff814b676f:	00
ffffffff814b6770:	89 ca                	mov    %ecx,%edx
ffffffff814b6772:	f7 d2                	not    %edx
ffffffff814b6774:	41 03 94 24 7c 01 00 	add    0x17c(%r12),%edx
ffffffff814b677b:	00
ffffffff814b677c:	81 e2 ff 0f 00 00    	and    $0xfff,%edx
ffffffff814b6782:	75 23                	jne    ffffffff814b67a7 <uart_put_char+0x87>
ffffffff814b6784:	48 89 c6             	mov    %rax,%rsi
ffffffff814b6787:	48 89 df             	mov    %rbx,%rdi
ffffffff814b678a:	e8 e1 64 58 00       	callq  ffffffff81a3cc70 <_raw_spin_unlock_irqrestore>
ffffffff814b678f:	44 89 e8             	mov    %r13d,%eax
ffffffff814b6792:	48 8b 1c 24          	mov    (%rsp),%rbx
ffffffff814b6796:	4c 8b 64 24 08       	mov    0x8(%rsp),%r12
ffffffff814b679b:	4c 8b 6c 24 10       	mov    0x10(%rsp),%r13
ffffffff814b67a0:	4c 8b 74 24 18       	mov    0x18(%rsp),%r14
ffffffff814b67a5:	c9                   	leaveq
ffffffff814b67a6:	c3                   	retq
ffffffff814b67a7:	49 8b 94 24 70 01 00 	mov    0x170(%r12),%rdx
ffffffff814b67ae:	00
ffffffff814b67af:	48 63 c9             	movslq %ecx,%rcx
ffffffff814b67b2:	41 b5 01             	mov    $0x1,%r13b
ffffffff814b67b5:	44 88 34 0a          	mov    %r14b,(%rdx,%rcx,1)
ffffffff814b67b9:	41 8b 94 24 78 01 00 	mov    0x178(%r12),%edx
ffffffff814b67c0:	00
ffffffff814b67c1:	83 c2 01             	add    $0x1,%edx
ffffffff814b67c4:	81 e2 ff 0f 00 00    	and    $0xfff,%edx
ffffffff814b67ca:	41 89 94 24 78 01 00 	mov    %edx,0x178(%r12)
ffffffff814b67d1:	00
ffffffff814b67d2:	eb b0                	jmp    ffffffff814b6784 <uart_put_char+0x64>
ffffffff814b67d4:	66 66 66 2e 0f 1f 84 	data32 data32 nopw %cs:0x0(%rax,%rax,1)
ffffffff814b67db:	00 00 00 00 00

for our build, this is crashing at:

    circ->buf[circ->head] = c;

Looking in uart_port_startup(), it seems that circ->buf (state->xmit.buf)
protected by the "per-port mutex", which based on uart_port_check() is
state->port.mutex. Indeed, the lock acquired in uart_put_char() is
uport->lock, i.e. not the same lock.

Anyway, since the lock is not acquired, if uart_shutdown() is called, the
last chunk of that function may release state->xmit.buf before its assigned
to null, and cause the race above.

To fix it, let's lock uport->lock when allocating/deallocating
state->xmit.buf in addition to the per-port mutex.

v2: switch to locking uport->lock on allocation/deallocation instead of
    locking the per-port mutex in uart_put_char. Note that since
    uport->lock is a spin lock, we have to switch the allocation to
    GFP_ATOMIC.
v3: move the allocation outside the lock, so we can switch back to
    GFP_KERNEL

Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Oct 3, 2018
commit 286e877 upstream.

Commit efda1b5 ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Introduced additional hardening for ambiguity in the ACPI spec for
ars_status output sizing. However, it had a couple of cases mixed up.
Where it should have been checking for (and returning) "out_field[1] -
4" it was using "out_field[1] - 8" and vice versa.

This caused a four byte discrepancy in the buffer size passed on to
the command handler, and in some cases, this caused memory corruption
like:

  ./daxdev-errors.sh: line 76: 24104 Aborted   (core dumped) ./daxdev-errors $busdev $region
  malloc(): memory corruption
  Program received signal SIGABRT, Aborted.
  [...]
  #5  0x00007ffff7865a2e in calloc () from /lib64/libc.so.6
  #6  0x00007ffff7bc2970 in ndctl_bus_cmd_new_ars_status (ars_cap=ars_cap@entry=0x6153b0) at ars.c:136
  #7  0x0000000000401644 in check_ars_status (check=0x7fffffffdeb0, bus=0x604c20) at daxdev-errors.c:144
  #8  test_daxdev_clear_error (region_name=<optimized out>, bus_name=<optimized out>)
      at daxdev-errors.c:332

Cc: <stable@vger.kernel.org>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Lukasz Dorau <lukasz.dorau@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Fixes: efda1b5 ("acpi, nfit, libnvdimm: fix / harden ars_status output length handling")
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-of-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Oct 3, 2018
[    8.014039] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:918
[    8.014041] in_atomic(): 0, irqs_disabled(): 1, pid: 78, name: kworker/u4:4
[    8.014045] CPU: 1 PID: 78 Comm: kworker/u4:4 Not tainted 4.1.7-rt7 #5
[    8.014055] Workqueue: events_unbound async_run_entry_fn
[    8.014059]  0000000000000000 ffff880037153748 ffffffff815f32c9 0000000000000002
[    8.014063]  ffff88013a50e380 ffff880037153768 ffffffff815ef075 ffff8800372c06c8
[    8.014066]  ffff8800372c06c8 ffff880037153778 ffffffff8107c0b3 ffff880037153798
[    8.014067] Call Trace:
[    8.014074]  [<ffffffff815f32c9>] dump_stack+0x4a/0x61
[    8.014078]  [<ffffffff815ef075>] ___might_sleep.part.93+0xe9/0xee
[    8.014082]  [<ffffffff8107c0b3>] ___might_sleep+0x53/0x80
[    8.014086]  [<ffffffff815f9064>] rt_spin_lock+0x24/0x50
[    8.014090]  [<ffffffff8109368b>] prepare_to_wait+0x2b/0xa0
[    8.014152]  [<ffffffffa016c04c>] intel_pipe_update_start+0x17c/0x300 [i915]
[    8.014156]  [<ffffffff81093b40>] ? prepare_to_wait_event+0x120/0x120
[    8.014201]  [<ffffffffa0158f36>] intel_begin_crtc_commit+0x166/0x1e0 [i915]
[    8.014215]  [<ffffffffa00c806d>] drm_atomic_helper_commit_planes+0x5d/0x1a0 [drm_kms_helper]
[    8.014260]  [<ffffffffa0171e9b>] intel_atomic_commit+0xab/0xf0 [i915]
[    8.014288]  [<ffffffffa00654c7>] drm_atomic_commit+0x37/0x60 [drm]
[    8.014298]  [<ffffffffa00c6fcd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
[    8.014301]  [<ffffffff815f77d9>] ? __ww_mutex_lock+0x39/0x40
[    8.014319]  [<ffffffffa0053b3d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
[    8.014328]  [<ffffffffa00c8edb>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
[    8.014337]  [<ffffffffa00cae49>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
[    8.014346]  [<ffffffffa00caec2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
[    8.014390]  [<ffffffffa016dfba>] intel_fbdev_set_par+0x1a/0x60 [i915]
[    8.014394]  [<ffffffff81327dc4>] fbcon_init+0x4f4/0x580
[    8.014398]  [<ffffffff8139ef4c>] visual_init+0xbc/0x120
[    8.014401]  [<ffffffff813a1623>] do_bind_con_driver+0x163/0x330
[    8.014405]  [<ffffffff813a1b2c>] do_take_over_console+0x11c/0x1c0
[    8.014408]  [<ffffffff813236e3>] do_fbcon_takeover+0x63/0xd0
[    8.014410]  [<ffffffff81328965>] fbcon_event_notify+0x785/0x8d0
[    8.014413]  [<ffffffff8107c12d>] ? __might_sleep+0x4d/0x90
[    8.014416]  [<ffffffff810775fe>] notifier_call_chain+0x4e/0x80
[    8.014419]  [<ffffffff810779cd>] __blocking_notifier_call_chain+0x4d/0x70
[    8.014422]  [<ffffffff81077a06>] blocking_notifier_call_chain+0x16/0x20
[    8.014425]  [<ffffffff8132b48b>] fb_notifier_call_chain+0x1b/0x20
[    8.014428]  [<ffffffff8132d8fa>] register_framebuffer+0x21a/0x350
[    8.014439]  [<ffffffffa00cb164>] drm_fb_helper_initial_config+0x274/0x3e0 [drm_kms_helper]
[    8.014483]  [<ffffffffa016f1cb>] intel_fbdev_initial_config+0x1b/0x20 [i915]
[    8.014486]  [<ffffffff8107912c>] async_run_entry_fn+0x4c/0x160
[    8.014490]  [<ffffffff81070ffa>] process_one_work+0x14a/0x470
[    8.014493]  [<ffffffff81071489>] worker_thread+0x169/0x4c0
[    8.014496]  [<ffffffff81071320>] ? process_one_work+0x470/0x470
[    8.014499]  [<ffffffff81076606>] kthread+0xc6/0xe0
[    8.014502]  [<ffffffff81070000>] ? queue_work_on+0x80/0x110
[    8.014506]  [<ffffffff81076540>] ? kthread_worker_fn+0x1c0/0x1c0

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
sys-oak pushed a commit that referenced this issue Nov 12, 2018
[    8.014039] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:918
[    8.014041] in_atomic(): 0, irqs_disabled(): 1, pid: 78, name: kworker/u4:4
[    8.014045] CPU: 1 PID: 78 Comm: kworker/u4:4 Not tainted 4.1.7-rt7 #5
[    8.014055] Workqueue: events_unbound async_run_entry_fn
[    8.014059]  0000000000000000 ffff880037153748 ffffffff815f32c9 0000000000000002
[    8.014063]  ffff88013a50e380 ffff880037153768 ffffffff815ef075 ffff8800372c06c8
[    8.014066]  ffff8800372c06c8 ffff880037153778 ffffffff8107c0b3 ffff880037153798
[    8.014067] Call Trace:
[    8.014074]  [<ffffffff815f32c9>] dump_stack+0x4a/0x61
[    8.014078]  [<ffffffff815ef075>] ___might_sleep.part.93+0xe9/0xee
[    8.014082]  [<ffffffff8107c0b3>] ___might_sleep+0x53/0x80
[    8.014086]  [<ffffffff815f9064>] rt_spin_lock+0x24/0x50
[    8.014090]  [<ffffffff8109368b>] prepare_to_wait+0x2b/0xa0
[    8.014152]  [<ffffffffa016c04c>] intel_pipe_update_start+0x17c/0x300 [i915]
[    8.014156]  [<ffffffff81093b40>] ? prepare_to_wait_event+0x120/0x120
[    8.014201]  [<ffffffffa0158f36>] intel_begin_crtc_commit+0x166/0x1e0 [i915]
[    8.014215]  [<ffffffffa00c806d>] drm_atomic_helper_commit_planes+0x5d/0x1a0 [drm_kms_helper]
[    8.014260]  [<ffffffffa0171e9b>] intel_atomic_commit+0xab/0xf0 [i915]
[    8.014288]  [<ffffffffa00654c7>] drm_atomic_commit+0x37/0x60 [drm]
[    8.014298]  [<ffffffffa00c6fcd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
[    8.014301]  [<ffffffff815f77d9>] ? __ww_mutex_lock+0x39/0x40
[    8.014319]  [<ffffffffa0053b3d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
[    8.014328]  [<ffffffffa00c8edb>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
[    8.014337]  [<ffffffffa00cae49>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
[    8.014346]  [<ffffffffa00caec2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
[    8.014390]  [<ffffffffa016dfba>] intel_fbdev_set_par+0x1a/0x60 [i915]
[    8.014394]  [<ffffffff81327dc4>] fbcon_init+0x4f4/0x580
[    8.014398]  [<ffffffff8139ef4c>] visual_init+0xbc/0x120
[    8.014401]  [<ffffffff813a1623>] do_bind_con_driver+0x163/0x330
[    8.014405]  [<ffffffff813a1b2c>] do_take_over_console+0x11c/0x1c0
[    8.014408]  [<ffffffff813236e3>] do_fbcon_takeover+0x63/0xd0
[    8.014410]  [<ffffffff81328965>] fbcon_event_notify+0x785/0x8d0
[    8.014413]  [<ffffffff8107c12d>] ? __might_sleep+0x4d/0x90
[    8.014416]  [<ffffffff810775fe>] notifier_call_chain+0x4e/0x80
[    8.014419]  [<ffffffff810779cd>] __blocking_notifier_call_chain+0x4d/0x70
[    8.014422]  [<ffffffff81077a06>] blocking_notifier_call_chain+0x16/0x20
[    8.014425]  [<ffffffff8132b48b>] fb_notifier_call_chain+0x1b/0x20
[    8.014428]  [<ffffffff8132d8fa>] register_framebuffer+0x21a/0x350
[    8.014439]  [<ffffffffa00cb164>] drm_fb_helper_initial_config+0x274/0x3e0 [drm_kms_helper]
[    8.014483]  [<ffffffffa016f1cb>] intel_fbdev_initial_config+0x1b/0x20 [i915]
[    8.014486]  [<ffffffff8107912c>] async_run_entry_fn+0x4c/0x160
[    8.014490]  [<ffffffff81070ffa>] process_one_work+0x14a/0x470
[    8.014493]  [<ffffffff81071489>] worker_thread+0x169/0x4c0
[    8.014496]  [<ffffffff81071320>] ? process_one_work+0x470/0x470
[    8.014499]  [<ffffffff81076606>] kthread+0xc6/0xe0
[    8.014502]  [<ffffffff81070000>] ? queue_work_on+0x80/0x110
[    8.014506]  [<ffffffff81076540>] ? kthread_worker_fn+0x1c0/0x1c0

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
sys-oak pushed a commit that referenced this issue Nov 20, 2018
commit c495144 upstream.

We're getting a lockdep splat because we take the dio_sem under the
log_mutex.  What we really need is to protect fsync() from logging an
extent map for an extent we never waited on higher up, so just guard the
whole thing with dio_sem.

======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Not tainted
------------------------------------------------------
aio-dio-invalid/30928 is trying to acquire lock:
0000000092621cfd (&mm->mmap_sem){++++}, at: get_user_pages_unlocked+0x5a/0x1e0

but task is already holding lock:
00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #5 (&ei->dio_sem){++++}:
       lock_acquire+0xbd/0x220
       down_write+0x51/0xb0
       btrfs_log_changed_extents+0x80/0xa40
       btrfs_log_inode+0xbaf/0x1000
       btrfs_log_inode_parent+0x26f/0xa80
       btrfs_log_dentry_safe+0x50/0x70
       btrfs_sync_file+0x357/0x540
       do_fsync+0x38/0x60
       __ia32_sys_fdatasync+0x12/0x20
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #4 (&ei->log_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_record_unlink_dir+0x2a/0xa0
       btrfs_unlink+0x5a/0xc0
       vfs_unlink+0xb1/0x1a0
       do_unlinkat+0x264/0x2b0
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #3 (sb_internal#2){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       start_transaction+0x3e6/0x590
       btrfs_evict_inode+0x475/0x640
       evict+0xbf/0x1b0
       btrfs_run_delayed_iputs+0x6c/0x90
       cleaner_kthread+0x124/0x1a0
       kthread+0x106/0x140
       ret_from_fork+0x3a/0x50

-> #2 (&fs_info->cleaner_delayed_iput_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_alloc_data_chunk_ondemand+0x197/0x530
       btrfs_check_data_free_space+0x4c/0x90
       btrfs_delalloc_reserve_space+0x20/0x60
       btrfs_page_mkwrite+0x87/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #1 (sb_pagefaults){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       btrfs_page_mkwrite+0x6a/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #0 (&mm->mmap_sem){++++}:
       __lock_acquire+0x42e/0x7a0
       lock_acquire+0xbd/0x220
       down_read+0x48/0xb0
       get_user_pages_unlocked+0x5a/0x1e0
       get_user_pages_fast+0xa4/0x150
       iov_iter_get_pages+0xc3/0x340
       do_direct_IO+0xf93/0x1d70
       __blockdev_direct_IO+0x32d/0x1c20
       btrfs_direct_IO+0x227/0x400
       generic_file_direct_write+0xcf/0x180
       btrfs_file_write_iter+0x308/0x58c
       aio_write+0xf8/0x1d0
       io_submit_one+0x3a9/0x620
       __ia32_compat_sys_io_submit+0xb2/0x270
       do_int80_syscall_32+0x5b/0x1a0
       entry_INT80_compat+0x88/0xa0

other info that might help us debug this:

Chain exists of:
  &mm->mmap_sem --> &ei->log_mutex --> &ei->dio_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->dio_sem);
                               lock(&ei->log_mutex);
                               lock(&ei->dio_sem);
  lock(&mm->mmap_sem);

 *** DEADLOCK ***

1 lock held by aio-dio-invalid/30928:
 #0: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

stack backtrace:
CPU: 0 PID: 30928 Comm: aio-dio-invalid Not tainted 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
 dump_stack+0x7c/0xbb
 print_circular_bug.isra.37+0x297/0x2a4
 check_prev_add.constprop.45+0x781/0x7a0
 ? __lock_acquire+0x42e/0x7a0
 validate_chain.isra.41+0x7f0/0xb00
 __lock_acquire+0x42e/0x7a0
 lock_acquire+0xbd/0x220
 ? get_user_pages_unlocked+0x5a/0x1e0
 down_read+0x48/0xb0
 ? get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_fast+0xa4/0x150
 iov_iter_get_pages+0xc3/0x340
 do_direct_IO+0xf93/0x1d70
 ? __alloc_workqueue_key+0x358/0x490
 ? __blockdev_direct_IO+0x14b/0x1c20
 __blockdev_direct_IO+0x32d/0x1c20
 ? btrfs_run_delalloc_work+0x40/0x40
 ? can_nocow_extent+0x490/0x490
 ? kvm_clock_read+0x1f/0x30
 ? can_nocow_extent+0x490/0x490
 ? btrfs_run_delalloc_work+0x40/0x40
 btrfs_direct_IO+0x227/0x400
 ? btrfs_run_delalloc_work+0x40/0x40
 generic_file_direct_write+0xcf/0x180
 btrfs_file_write_iter+0x308/0x58c
 aio_write+0xf8/0x1d0
 ? kvm_clock_read+0x1f/0x30
 ? __might_fault+0x3e/0x90
 io_submit_one+0x3a9/0x620
 ? io_submit_one+0xe5/0x620
 __ia32_compat_sys_io_submit+0xb2/0x270
 do_int80_syscall_32+0x5b/0x1a0
 entry_INT80_compat+0x88/0xa0

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Nov 20, 2018
Fixes a crash when the report encounters an address that could not be
associated with an mmaped region:

  #0  0x00005555557bdc4a in callchain_srcline (ip=<error reading variable: Cannot access memory at address 0x38>, sym=0x0, map=0x0) at util/machine.c:2329
  #1  unwind_entry (entry=entry@entry=0x7fffffff9180, arg=arg@entry=0x7ffff5642498) at util/machine.c:2329
  #2  0x00005555558370af in entry (arg=0x7ffff5642498, cb=0x5555557bdb50 <unwind_entry>, thread=<optimized out>, ip=18446744073709551615) at util/unwind-libunwind-local.c:586
  #3  get_entries (ui=ui@entry=0x7fffffff9620, cb=0x5555557bdb50 <unwind_entry>, arg=0x7ffff5642498, max_stack=<optimized out>) at util/unwind-libunwind-local.c:703
  #4  0x0000555555837192 in _unwind__get_entries (cb=<optimized out>, arg=<optimized out>, thread=<optimized out>, data=<optimized out>, max_stack=<optimized out>) at util/unwind-libunwind-local.c:725
  #5  0x00005555557c310f in thread__resolve_callchain_unwind (max_stack=127, sample=0x7fffffff9830, evsel=0x555555c7b3b0, cursor=0x7ffff5642498, thread=0x555555c7f6f0) at util/machine.c:2351
  #6  thread__resolve_callchain (thread=0x555555c7f6f0, cursor=0x7ffff5642498, evsel=0x555555c7b3b0, sample=0x7fffffff9830, parent=0x7fffffff97b8, root_al=0x7fffffff9750, max_stack=127) at util/machine.c:2378
  #7  0x00005555557ba4ee in sample__resolve_callchain (sample=<optimized out>, cursor=<optimized out>, parent=parent@entry=0x7fffffff97b8, evsel=<optimized out>, al=al@entry=0x7fffffff9750,
      max_stack=<optimized out>) at util/callchain.c:1085

Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Tested-by: Sandipan Das <sandipan@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 2a9d505 ("perf script: Show correct offsets for DWARF-based unwinding")
Link: http://lkml.kernel.org/r/20180926135207.30263-1-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
sys-oak pushed a commit that referenced this issue Nov 20, 2018
This reverts commit d76c743.

While commit d76c743 ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren <tony@atomide.com>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Fixes: d76c743 ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Nov 20, 2018
When the function name for an inline frame is invalid, we must not try
to demangle this symbol, otherwise we crash with:

  #0  0x0000555555895c01 in bfd_demangle ()
  #1  0x0000555555823262 in demangle_sym (dso=0x555555d92b90, elf_name=0x0, kmodule=0) at util/symbol-elf.c:215
  #2  dso__demangle_sym (dso=dso@entry=0x555555d92b90, kmodule=<optimized out>, kmodule@entry=0, elf_name=elf_name@entry=0x0) at util/symbol-elf.c:400
  #3  0x00005555557fef4b in new_inline_sym (funcname=0x0, base_sym=0x555555d92b90, dso=0x555555d92b90) at util/srcline.c:89
  #4  inline_list__append_dso_a2l (dso=dso@entry=0x555555c7bb00, node=node@entry=0x555555e31810, sym=sym@entry=0x555555d92b90) at util/srcline.c:264
  #5  0x00005555557ff27f in addr2line (dso_name=dso_name@entry=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf", addr=addr@entry=2888, file=file@entry=0x0,
      line=line@entry=0x0, dso=dso@entry=0x555555c7bb00, unwind_inlines=unwind_inlines@entry=true, node=0x555555e31810, sym=0x555555d92b90) at util/srcline.c:313
  #6  0x00005555557ffe7c in addr2inlines (sym=0x555555d92b90, dso=0x555555c7bb00, addr=2888, dso_name=0x555555d92430 "/home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf")
      at util/srcline.c:358

So instead handle the case where we get invalid function names for
inlined frames and use a fallback '??' function name instead.

While this crash was originally reported by Hadrien for rust code, I can
now also reproduce it with trivial C++ code. Indeed, it seems like
libbfd fails to interpret the debug information for the inline frame
symbol name:

  $ addr2line -e /home/milian/.debug/.build-id/f7/186d14bb94f3c6161c010926da66033d24fce5/elf -if b48
  main
  /usr/include/c++/8.2.1/complex:610
  ??
  /usr/include/c++/8.2.1/complex:618
  ??
  /usr/include/c++/8.2.1/complex:675
  ??
  /usr/include/c++/8.2.1/complex:685
  main
  /home/milian/projects/kdab/rnd/hotspot/tests/test-clients/cpp-inlining/main.cpp:39

I've reported this bug upstream and also attached a patch there which
should fix this issue:

https://sourceware.org/bugzilla/show_bug.cgi?id=23715

Reported-by: Hadrien Grasland <grasland@lal.in2p3.fr>
Signed-off-by: Milian Wolff <milian.wolff@kdab.com>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: a64489c ("perf report: Find the inline stack for a given address")
[ The above 'Fixes:' cset is where originally the problem was
  introduced, i.e.  using a2l->funcname without checking if it is NULL,
  but this current patch fixes the current codebase, i.e. multiple csets
  were applied after a64489c before the problem was reported by Hadrien ]
Link: http://lkml.kernel.org/r/20180926135207.30263-3-milian.wolff@kdab.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
sys-oak pushed a commit that referenced this issue Dec 4, 2018
commit c495144 upstream.

We're getting a lockdep splat because we take the dio_sem under the
log_mutex.  What we really need is to protect fsync() from logging an
extent map for an extent we never waited on higher up, so just guard the
whole thing with dio_sem.

======================================================
WARNING: possible circular locking dependency detected
4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411 Not tainted
------------------------------------------------------
aio-dio-invalid/30928 is trying to acquire lock:
0000000092621cfd (&mm->mmap_sem){++++}, at: get_user_pages_unlocked+0x5a/0x1e0

but task is already holding lock:
00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

-> #5 (&ei->dio_sem){++++}:
       lock_acquire+0xbd/0x220
       down_write+0x51/0xb0
       btrfs_log_changed_extents+0x80/0xa40
       btrfs_log_inode+0xbaf/0x1000
       btrfs_log_inode_parent+0x26f/0xa80
       btrfs_log_dentry_safe+0x50/0x70
       btrfs_sync_file+0x357/0x540
       do_fsync+0x38/0x60
       __ia32_sys_fdatasync+0x12/0x20
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #4 (&ei->log_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_record_unlink_dir+0x2a/0xa0
       btrfs_unlink+0x5a/0xc0
       vfs_unlink+0xb1/0x1a0
       do_unlinkat+0x264/0x2b0
       do_fast_syscall_32+0x9a/0x2f0
       entry_SYSENTER_compat+0x84/0x96

-> #3 (sb_internal#2){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       start_transaction+0x3e6/0x590
       btrfs_evict_inode+0x475/0x640
       evict+0xbf/0x1b0
       btrfs_run_delayed_iputs+0x6c/0x90
       cleaner_kthread+0x124/0x1a0
       kthread+0x106/0x140
       ret_from_fork+0x3a/0x50

-> #2 (&fs_info->cleaner_delayed_iput_mutex){+.+.}:
       lock_acquire+0xbd/0x220
       __mutex_lock+0x86/0xa10
       btrfs_alloc_data_chunk_ondemand+0x197/0x530
       btrfs_check_data_free_space+0x4c/0x90
       btrfs_delalloc_reserve_space+0x20/0x60
       btrfs_page_mkwrite+0x87/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #1 (sb_pagefaults){.+.+}:
       lock_acquire+0xbd/0x220
       __sb_start_write+0x14d/0x230
       btrfs_page_mkwrite+0x6a/0x520
       do_page_mkwrite+0x31/0xa0
       __handle_mm_fault+0x799/0xb00
       handle_mm_fault+0x7c/0xe0
       __do_page_fault+0x1d3/0x4a0
       async_page_fault+0x1e/0x30

-> #0 (&mm->mmap_sem){++++}:
       __lock_acquire+0x42e/0x7a0
       lock_acquire+0xbd/0x220
       down_read+0x48/0xb0
       get_user_pages_unlocked+0x5a/0x1e0
       get_user_pages_fast+0xa4/0x150
       iov_iter_get_pages+0xc3/0x340
       do_direct_IO+0xf93/0x1d70
       __blockdev_direct_IO+0x32d/0x1c20
       btrfs_direct_IO+0x227/0x400
       generic_file_direct_write+0xcf/0x180
       btrfs_file_write_iter+0x308/0x58c
       aio_write+0xf8/0x1d0
       io_submit_one+0x3a9/0x620
       __ia32_compat_sys_io_submit+0xb2/0x270
       do_int80_syscall_32+0x5b/0x1a0
       entry_INT80_compat+0x88/0xa0

other info that might help us debug this:

Chain exists of:
  &mm->mmap_sem --> &ei->log_mutex --> &ei->dio_sem

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ei->dio_sem);
                               lock(&ei->log_mutex);
                               lock(&ei->dio_sem);
  lock(&mm->mmap_sem);

 *** DEADLOCK ***

1 lock held by aio-dio-invalid/30928:
 #0: 00000000cefe6b35 (&ei->dio_sem){++++}, at: btrfs_direct_IO+0x3be/0x400

stack backtrace:
CPU: 0 PID: 30928 Comm: aio-dio-invalid Not tainted 4.18.0-rc4-xfstests-00025-g5de5edbaf1d4 #411
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-2.el7 04/01/2014
Call Trace:
 dump_stack+0x7c/0xbb
 print_circular_bug.isra.37+0x297/0x2a4
 check_prev_add.constprop.45+0x781/0x7a0
 ? __lock_acquire+0x42e/0x7a0
 validate_chain.isra.41+0x7f0/0xb00
 __lock_acquire+0x42e/0x7a0
 lock_acquire+0xbd/0x220
 ? get_user_pages_unlocked+0x5a/0x1e0
 down_read+0x48/0xb0
 ? get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_unlocked+0x5a/0x1e0
 get_user_pages_fast+0xa4/0x150
 iov_iter_get_pages+0xc3/0x340
 do_direct_IO+0xf93/0x1d70
 ? __alloc_workqueue_key+0x358/0x490
 ? __blockdev_direct_IO+0x14b/0x1c20
 __blockdev_direct_IO+0x32d/0x1c20
 ? btrfs_run_delalloc_work+0x40/0x40
 ? can_nocow_extent+0x490/0x490
 ? kvm_clock_read+0x1f/0x30
 ? can_nocow_extent+0x490/0x490
 ? btrfs_run_delalloc_work+0x40/0x40
 btrfs_direct_IO+0x227/0x400
 ? btrfs_run_delalloc_work+0x40/0x40
 generic_file_direct_write+0xcf/0x180
 btrfs_file_write_iter+0x308/0x58c
 aio_write+0xf8/0x1d0
 ? kvm_clock_read+0x1f/0x30
 ? __might_fault+0x3e/0x90
 io_submit_one+0x3a9/0x620
 ? io_submit_one+0xe5/0x620
 __ia32_compat_sys_io_submit+0xb2/0x270
 do_int80_syscall_32+0x5b/0x1a0
 entry_INT80_compat+0x88/0xa0

CC: stable@vger.kernel.org # 4.14+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Dec 21, 2018
[ Upstream commit c5a94f4 ]

It was observed that a process blocked indefintely in
__fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP
to be cleared via fscache_wait_for_deferred_lookup().

At this time, ->backing_objects was empty, which would normaly prevent
__fscache_read_or_alloc_page() from getting to the point of waiting.
This implies that ->backing_objects was cleared *after*
__fscache_read_or_alloc_page was was entered.

When an object is "killed" and then "dropped",
FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then
KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is
->backing_objects cleared.  This leaves a window where
something else can set FSCACHE_COOKIE_LOOKING_UP and
__fscache_read_or_alloc_page() can start waiting, before
->backing_objects is cleared

There is some uncertainty in this analysis, but it seems to be fit the
observations.  Adding the wake in this patch will be handled correctly
by __fscache_read_or_alloc_page(), as it checks if ->backing_objects
is empty again, after waiting.

Customer which reported the hang, also report that the hang cannot be
reproduced with this fix.

The backtrace for the blocked process looked like:

PID: 29360  TASK: ffff881ff2ac0f80  CPU: 3   COMMAND: "zsh"
 #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1
 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed
 #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8
 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e
 #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache]
 #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache]
 #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs]
 #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs]
 #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73
 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs]
#10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756
#11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa
#12 [ffff881ff43eff18] sys_read at ffffffff811fda62
#13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jan 8, 2019
[ Upstream commit ebaf39e ]

The *_frag_reasm() functions are susceptible to miscalculating the byte
count of packet fragments in case the truesize of a head buffer changes.
The truesize member may be changed by the call to skb_unclone(), leaving
the fragment memory limit counter unbalanced even if all fragments are
processed. This miscalculation goes unnoticed as long as the network
namespace which holds the counter is not destroyed.

Should an attempt be made to destroy a network namespace that holds an
unbalanced fragment memory limit counter the cleanup of the namespace
never finishes. The thread handling the cleanup gets stuck in
inet_frags_exit_net() waiting for the percpu counter to reach zero. The
thread is usually in running state with a stacktrace similar to:

 PID: 1073   TASK: ffff880626711440  CPU: 1   COMMAND: "kworker/u48:4"
  #5 [ffff880621563d48] _raw_spin_lock at ffffffff815f5480
  #6 [ffff880621563d48] inet_evict_bucket at ffffffff8158020b
  #7 [ffff880621563d80] inet_frags_exit_net at ffffffff8158051c
  #8 [ffff880621563db0] ops_exit_list at ffffffff814f5856
  #9 [ffff880621563dd8] cleanup_net at ffffffff814f67c0
 #10 [ffff880621563e38] process_one_work at ffffffff81096f14

It is not possible to create new network namespaces, and processes
that call unshare() end up being stuck in uninterruptible sleep state
waiting to acquire the net_mutex.

The bug was observed in the IPv6 netfilter code by Per Sundstrom.
I thank him for his analysis of the problem. The parts of this patch
that apply to IPv4 and IPv6 fragment reassembly are preemptive measures.

Signed-off-by: Jiri Wiesner <jwiesner@suse.com>
Reported-by: Per Sundstrom <per.sundstrom@redqube.se>
Acked-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jan 8, 2019
[ Upstream commit c5a94f4 ]

It was observed that a process blocked indefintely in
__fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP
to be cleared via fscache_wait_for_deferred_lookup().

At this time, ->backing_objects was empty, which would normaly prevent
__fscache_read_or_alloc_page() from getting to the point of waiting.
This implies that ->backing_objects was cleared *after*
__fscache_read_or_alloc_page was was entered.

When an object is "killed" and then "dropped",
FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then
KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is
->backing_objects cleared.  This leaves a window where
something else can set FSCACHE_COOKIE_LOOKING_UP and
__fscache_read_or_alloc_page() can start waiting, before
->backing_objects is cleared

There is some uncertainty in this analysis, but it seems to be fit the
observations.  Adding the wake in this patch will be handled correctly
by __fscache_read_or_alloc_page(), as it checks if ->backing_objects
is empty again, after waiting.

Customer which reported the hang, also report that the hang cannot be
reproduced with this fix.

The backtrace for the blocked process looked like:

PID: 29360  TASK: ffff881ff2ac0f80  CPU: 3   COMMAND: "zsh"
 #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1
 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed
 #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8
 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e
 #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache]
 #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache]
 #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs]
 #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs]
 #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73
 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs]
#10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756
#11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa
#12 [ffff881ff43eff18] sys_read at ffffffff811fda62
#13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jan 15, 2019
[ Upstream commit ebaf39e ]

The *_frag_reasm() functions are susceptible to miscalculating the byte
count of packet fragments in case the truesize of a head buffer changes.
The truesize member may be changed by the call to skb_unclone(), leaving
the fragment memory limit counter unbalanced even if all fragments are
processed. This miscalculation goes unnoticed as long as the network
namespace which holds the counter is not destroyed.

Should an attempt be made to destroy a network namespace that holds an
unbalanced fragment memory limit counter the cleanup of the namespace
never finishes. The thread handling the cleanup gets stuck in
inet_frags_exit_net() waiting for the percpu counter to reach zero. The
thread is usually in running state with a stacktrace similar to:

 PID: 1073   TASK: ffff880626711440  CPU: 1   COMMAND: "kworker/u48:4"
  #5 [ffff880621563d48] _raw_spin_lock at ffffffff815f5480
  #6 [ffff880621563d48] inet_evict_bucket at ffffffff8158020b
  #7 [ffff880621563d80] inet_frags_exit_net at ffffffff8158051c
  #8 [ffff880621563db0] ops_exit_list at ffffffff814f5856
  #9 [ffff880621563dd8] cleanup_net at ffffffff814f67c0
 #10 [ffff880621563e38] process_one_work at ffffffff81096f14

It is not possible to create new network namespaces, and processes
that call unshare() end up being stuck in uninterruptible sleep state
waiting to acquire the net_mutex.

The bug was observed in the IPv6 netfilter code by Per Sundstrom.
I thank him for his analysis of the problem. The parts of this patch
that apply to IPv4 and IPv6 fragment reassembly are preemptive measures.

Signed-off-by: Jiri Wiesner <jwiesner@suse.com>
Reported-by: Per Sundstrom <per.sundstrom@redqube.se>
Acked-by: Peter Oskolkov <posk@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jan 15, 2019
[ Upstream commit c5a94f4 ]

It was observed that a process blocked indefintely in
__fscache_read_or_alloc_page(), waiting for FSCACHE_COOKIE_LOOKING_UP
to be cleared via fscache_wait_for_deferred_lookup().

At this time, ->backing_objects was empty, which would normaly prevent
__fscache_read_or_alloc_page() from getting to the point of waiting.
This implies that ->backing_objects was cleared *after*
__fscache_read_or_alloc_page was was entered.

When an object is "killed" and then "dropped",
FSCACHE_COOKIE_LOOKING_UP is cleared in fscache_lookup_failure(), then
KILL_OBJECT and DROP_OBJECT are "called" and only in DROP_OBJECT is
->backing_objects cleared.  This leaves a window where
something else can set FSCACHE_COOKIE_LOOKING_UP and
__fscache_read_or_alloc_page() can start waiting, before
->backing_objects is cleared

There is some uncertainty in this analysis, but it seems to be fit the
observations.  Adding the wake in this patch will be handled correctly
by __fscache_read_or_alloc_page(), as it checks if ->backing_objects
is empty again, after waiting.

Customer which reported the hang, also report that the hang cannot be
reproduced with this fix.

The backtrace for the blocked process looked like:

PID: 29360  TASK: ffff881ff2ac0f80  CPU: 3   COMMAND: "zsh"
 #0 [ffff881ff43efbf8] schedule at ffffffff815e56f1
 #1 [ffff881ff43efc58] bit_wait at ffffffff815e64ed
 #2 [ffff881ff43efc68] __wait_on_bit at ffffffff815e61b8
 #3 [ffff881ff43efca0] out_of_line_wait_on_bit at ffffffff815e625e
 #4 [ffff881ff43efd08] fscache_wait_for_deferred_lookup at ffffffffa04f2e8f [fscache]
 #5 [ffff881ff43efd18] __fscache_read_or_alloc_page at ffffffffa04f2ffe [fscache]
 #6 [ffff881ff43efd58] __nfs_readpage_from_fscache at ffffffffa0679668 [nfs]
 #7 [ffff881ff43efd78] nfs_readpage at ffffffffa067092b [nfs]
 #8 [ffff881ff43efda0] generic_file_read_iter at ffffffff81187a73
 #9 [ffff881ff43efe50] nfs_file_read at ffffffffa066544b [nfs]
#10 [ffff881ff43efe70] __vfs_read at ffffffff811fc756
#11 [ffff881ff43efee8] vfs_read at ffffffff811fccfa
#12 [ffff881ff43eff18] sys_read at ffffffff811fda62
#13 [ffff881ff43eff50] entry_SYSCALL_64_fastpath at ffffffff815e986e

Signed-off-by: NeilBrown <neilb@suse.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jan 19, 2019
[    8.014039] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:918
[    8.014041] in_atomic(): 0, irqs_disabled(): 1, pid: 78, name: kworker/u4:4
[    8.014045] CPU: 1 PID: 78 Comm: kworker/u4:4 Not tainted 4.1.7-rt7 #5
[    8.014055] Workqueue: events_unbound async_run_entry_fn
[    8.014059]  0000000000000000 ffff880037153748 ffffffff815f32c9 0000000000000002
[    8.014063]  ffff88013a50e380 ffff880037153768 ffffffff815ef075 ffff8800372c06c8
[    8.014066]  ffff8800372c06c8 ffff880037153778 ffffffff8107c0b3 ffff880037153798
[    8.014067] Call Trace:
[    8.014074]  [<ffffffff815f32c9>] dump_stack+0x4a/0x61
[    8.014078]  [<ffffffff815ef075>] ___might_sleep.part.93+0xe9/0xee
[    8.014082]  [<ffffffff8107c0b3>] ___might_sleep+0x53/0x80
[    8.014086]  [<ffffffff815f9064>] rt_spin_lock+0x24/0x50
[    8.014090]  [<ffffffff8109368b>] prepare_to_wait+0x2b/0xa0
[    8.014152]  [<ffffffffa016c04c>] intel_pipe_update_start+0x17c/0x300 [i915]
[    8.014156]  [<ffffffff81093b40>] ? prepare_to_wait_event+0x120/0x120
[    8.014201]  [<ffffffffa0158f36>] intel_begin_crtc_commit+0x166/0x1e0 [i915]
[    8.014215]  [<ffffffffa00c806d>] drm_atomic_helper_commit_planes+0x5d/0x1a0 [drm_kms_helper]
[    8.014260]  [<ffffffffa0171e9b>] intel_atomic_commit+0xab/0xf0 [i915]
[    8.014288]  [<ffffffffa00654c7>] drm_atomic_commit+0x37/0x60 [drm]
[    8.014298]  [<ffffffffa00c6fcd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
[    8.014301]  [<ffffffff815f77d9>] ? __ww_mutex_lock+0x39/0x40
[    8.014319]  [<ffffffffa0053b3d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
[    8.014328]  [<ffffffffa00c8edb>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
[    8.014337]  [<ffffffffa00cae49>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
[    8.014346]  [<ffffffffa00caec2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
[    8.014390]  [<ffffffffa016dfba>] intel_fbdev_set_par+0x1a/0x60 [i915]
[    8.014394]  [<ffffffff81327dc4>] fbcon_init+0x4f4/0x580
[    8.014398]  [<ffffffff8139ef4c>] visual_init+0xbc/0x120
[    8.014401]  [<ffffffff813a1623>] do_bind_con_driver+0x163/0x330
[    8.014405]  [<ffffffff813a1b2c>] do_take_over_console+0x11c/0x1c0
[    8.014408]  [<ffffffff813236e3>] do_fbcon_takeover+0x63/0xd0
[    8.014410]  [<ffffffff81328965>] fbcon_event_notify+0x785/0x8d0
[    8.014413]  [<ffffffff8107c12d>] ? __might_sleep+0x4d/0x90
[    8.014416]  [<ffffffff810775fe>] notifier_call_chain+0x4e/0x80
[    8.014419]  [<ffffffff810779cd>] __blocking_notifier_call_chain+0x4d/0x70
[    8.014422]  [<ffffffff81077a06>] blocking_notifier_call_chain+0x16/0x20
[    8.014425]  [<ffffffff8132b48b>] fb_notifier_call_chain+0x1b/0x20
[    8.014428]  [<ffffffff8132d8fa>] register_framebuffer+0x21a/0x350
[    8.014439]  [<ffffffffa00cb164>] drm_fb_helper_initial_config+0x274/0x3e0 [drm_kms_helper]
[    8.014483]  [<ffffffffa016f1cb>] intel_fbdev_initial_config+0x1b/0x20 [i915]
[    8.014486]  [<ffffffff8107912c>] async_run_entry_fn+0x4c/0x160
[    8.014490]  [<ffffffff81070ffa>] process_one_work+0x14a/0x470
[    8.014493]  [<ffffffff81071489>] worker_thread+0x169/0x4c0
[    8.014496]  [<ffffffff81071320>] ? process_one_work+0x470/0x470
[    8.014499]  [<ffffffff81076606>] kthread+0xc6/0xe0
[    8.014502]  [<ffffffff81070000>] ? queue_work_on+0x80/0x110
[    8.014506]  [<ffffffff81076540>] ? kthread_worker_fn+0x1c0/0x1c0

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
@Minipada
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I'm having the same issue, was it solved?

@rvgodbol
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4.9 in sustaining mode and this is only a warning. This code was re-factored in 4.14.

@bjwood05
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I wanted to provide a little more detail about the issue and the sysfs symlink warning race condition that can be intermittently encountered. For the 4.9 kernel the initial solution for usb dual role mode switching added the usb_phy platform device creation/add in both the dwc3 and xhci pci drivers to prevent a delay when coming out of suspend (or during initialization if one or both of these drivers were set to 'm' in the kernel defconfig). The result would be that intermittently a dmesg warning might appear stating that the sysfs symlink for "intel_usb_dr_phy" was attempting to be duplicated. In the 4.14 this code was completely rewritten so it could be pushed to the upstream kernel in the "devcon" driver.

sys-oak pushed a commit that referenced this issue Jan 30, 2019
[ Upstream commit 30522a9 ]

Currently registering CvP managers works only for first probed CvP
device, for all other devices it is refused due to duplicated chkcfg
sysfs entry:

fpga_manager fpga3: Altera CvP FPGA Manager @0000:0c:00.0 registered
sysfs: cannot create duplicate filename '/bus/pci/drivers/altera-cvp/chkcfg'
CPU: 0 PID: 3808 Comm: bash Tainted: G           O      4.19.0-custom+ #5
Call Trace:
  dump_stack+0x46/0x5b
  sysfs_warn_dup+0x53/0x60
  sysfs_add_file_mode_ns+0x16d/0x180
  sysfs_create_file_ns+0x51/0x60
  altera_cvp_probe+0x16f/0x2a0 [altera_cvp]
  local_pci_probe+0x3f/0xa0
  ? pci_match_device+0xb1/0xf0
  pci_device_probe+0x116/0x170
  really_probe+0x21b/0x2c0
  driver_probe_device+0x4b/0xe0
  bind_store+0xcb/0x130
  kernfs_fop_write+0xfd/0x180
  __vfs_write+0x21/0x150
  ? selinux_file_permission+0xdc/0x130
  vfs_write+0xa8/0x1a0
  ? find_vma+0xd/0x60
  ksys_write+0x3d/0x90
  do_syscall_64+0x44/0xf0
  entry_SYSCALL_64_after_hwframe+0x44/0xa9
  ...
 altera-cvp 0000:0c:00.0: Can't create sysfs chkcfg file
 fpga_manager fpga3: fpga_mgr_unregister Altera CvP FPGA Manager @0000:0c:00.0

Move chkcfg creation to module init as suggested by Alan.

Signed-off-by: Anatolij Gustschin <agust@denx.de>
Acked-by: Alan Tull <atull@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jan 30, 2019
…ong enough

[ Upstream commit ad66950 ]

A session must only be released after all code that accesses the session
structure has finished. Make sure that this is the case by introducing a
new command counter per session that is only decremented after the
.release_cmd() callback has finished. This patch fixes the following crash:

BUG: KASAN: use-after-free in do_raw_spin_lock+0x1c/0x130
Read of size 4 at addr ffff8801534b16e4 by task rmdir/14805
CPU: 16 PID: 14805 Comm: rmdir Not tainted 4.18.0-rc2-dbg+ #5
Call Trace:
dump_stack+0xa4/0xf5
print_address_description+0x6f/0x270
kasan_report+0x241/0x360
__asan_load4+0x78/0x80
do_raw_spin_lock+0x1c/0x130
_raw_spin_lock_irqsave+0x52/0x60
srpt_set_ch_state+0x27/0x70 [ib_srpt]
srpt_disconnect_ch+0x1b/0xc0 [ib_srpt]
srpt_close_session+0xa8/0x260 [ib_srpt]
target_shutdown_sessions+0x170/0x180 [target_core_mod]
core_tpg_del_initiator_node_acl+0xf3/0x200 [target_core_mod]
target_fabric_nacl_base_release+0x25/0x30 [target_core_mod]
config_item_release+0x9c/0x110 [configfs]
config_item_put+0x26/0x30 [configfs]
configfs_rmdir+0x3b8/0x510 [configfs]
vfs_rmdir+0xb3/0x1e0
do_rmdir+0x262/0x2c0
do_syscall_64+0x77/0x230
entry_SYSCALL_64_after_hwframe+0x49/0xbe

Cc: Nicholas Bellinger <nab@linux-iscsi.org>
Cc: Mike Christie <mchristi@redhat.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: David Disseldorp <ddiss@suse.de>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jan 30, 2019
[    8.014039] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:918
[    8.014041] in_atomic(): 0, irqs_disabled(): 1, pid: 78, name: kworker/u4:4
[    8.014045] CPU: 1 PID: 78 Comm: kworker/u4:4 Not tainted 4.1.7-rt7 #5
[    8.014055] Workqueue: events_unbound async_run_entry_fn
[    8.014059]  0000000000000000 ffff880037153748 ffffffff815f32c9 0000000000000002
[    8.014063]  ffff88013a50e380 ffff880037153768 ffffffff815ef075 ffff8800372c06c8
[    8.014066]  ffff8800372c06c8 ffff880037153778 ffffffff8107c0b3 ffff880037153798
[    8.014067] Call Trace:
[    8.014074]  [<ffffffff815f32c9>] dump_stack+0x4a/0x61
[    8.014078]  [<ffffffff815ef075>] ___might_sleep.part.93+0xe9/0xee
[    8.014082]  [<ffffffff8107c0b3>] ___might_sleep+0x53/0x80
[    8.014086]  [<ffffffff815f9064>] rt_spin_lock+0x24/0x50
[    8.014090]  [<ffffffff8109368b>] prepare_to_wait+0x2b/0xa0
[    8.014152]  [<ffffffffa016c04c>] intel_pipe_update_start+0x17c/0x300 [i915]
[    8.014156]  [<ffffffff81093b40>] ? prepare_to_wait_event+0x120/0x120
[    8.014201]  [<ffffffffa0158f36>] intel_begin_crtc_commit+0x166/0x1e0 [i915]
[    8.014215]  [<ffffffffa00c806d>] drm_atomic_helper_commit_planes+0x5d/0x1a0 [drm_kms_helper]
[    8.014260]  [<ffffffffa0171e9b>] intel_atomic_commit+0xab/0xf0 [i915]
[    8.014288]  [<ffffffffa00654c7>] drm_atomic_commit+0x37/0x60 [drm]
[    8.014298]  [<ffffffffa00c6fcd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
[    8.014301]  [<ffffffff815f77d9>] ? __ww_mutex_lock+0x39/0x40
[    8.014319]  [<ffffffffa0053b3d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
[    8.014328]  [<ffffffffa00c8edb>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
[    8.014337]  [<ffffffffa00cae49>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
[    8.014346]  [<ffffffffa00caec2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
[    8.014390]  [<ffffffffa016dfba>] intel_fbdev_set_par+0x1a/0x60 [i915]
[    8.014394]  [<ffffffff81327dc4>] fbcon_init+0x4f4/0x580
[    8.014398]  [<ffffffff8139ef4c>] visual_init+0xbc/0x120
[    8.014401]  [<ffffffff813a1623>] do_bind_con_driver+0x163/0x330
[    8.014405]  [<ffffffff813a1b2c>] do_take_over_console+0x11c/0x1c0
[    8.014408]  [<ffffffff813236e3>] do_fbcon_takeover+0x63/0xd0
[    8.014410]  [<ffffffff81328965>] fbcon_event_notify+0x785/0x8d0
[    8.014413]  [<ffffffff8107c12d>] ? __might_sleep+0x4d/0x90
[    8.014416]  [<ffffffff810775fe>] notifier_call_chain+0x4e/0x80
[    8.014419]  [<ffffffff810779cd>] __blocking_notifier_call_chain+0x4d/0x70
[    8.014422]  [<ffffffff81077a06>] blocking_notifier_call_chain+0x16/0x20
[    8.014425]  [<ffffffff8132b48b>] fb_notifier_call_chain+0x1b/0x20
[    8.014428]  [<ffffffff8132d8fa>] register_framebuffer+0x21a/0x350
[    8.014439]  [<ffffffffa00cb164>] drm_fb_helper_initial_config+0x274/0x3e0 [drm_kms_helper]
[    8.014483]  [<ffffffffa016f1cb>] intel_fbdev_initial_config+0x1b/0x20 [i915]
[    8.014486]  [<ffffffff8107912c>] async_run_entry_fn+0x4c/0x160
[    8.014490]  [<ffffffff81070ffa>] process_one_work+0x14a/0x470
[    8.014493]  [<ffffffff81071489>] worker_thread+0x169/0x4c0
[    8.014496]  [<ffffffff81071320>] ? process_one_work+0x470/0x470
[    8.014499]  [<ffffffff81076606>] kthread+0xc6/0xe0
[    8.014502]  [<ffffffff81070000>] ? queue_work_on+0x80/0x110
[    8.014506]  [<ffffffff81076540>] ? kthread_worker_fn+0x1c0/0x1c0

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
sys-oak pushed a commit that referenced this issue Feb 1, 2019
Otherwise we end up with the following:

|=================================
|[ INFO: inconsistent lock state ]
|4.4.2-rt7+ #5 Not tainted
|---------------------------------
|inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
|ktimersoftd/0/4 [HC0[0]:SC0[0]:HE1:SE1] takes:
| (tick_broadcast_lock){?.....}, at: [<ffffffc000150db4>] tick_handle_oneshot_broadcast+0x58/0x27c
|{IN-HARDIRQ-W} state was registered at:
|  [<ffffffc000118198>] mark_lock+0x19c/0x6a0
|  [<ffffffc000119728>] __lock_acquire+0xb1c/0x2100
|  [<ffffffc00011b560>] lock_acquire+0xf8/0x230
|  [<ffffffc00061bf08>] _raw_spin_lock_irqsave+0x50/0x68
|  [<ffffffc000152188>] tick_broadcast_switch_to_oneshot+0x20/0x60
|  [<ffffffc0001529f4>] tick_switch_to_oneshot+0x64/0xd8
|  [<ffffffc000152b00>] tick_init_highres+0x1c/0x24
|  [<ffffffc000141e58>] hrtimer_run_queues+0x78/0x100
|  [<ffffffc00013f804>] update_process_times+0x38/0x74
|  [<ffffffc00014fc5c>] tick_periodic+0x60/0x140
|  [<ffffffc00014fd68>] tick_handle_periodic+0x2c/0x94
|  [<ffffffc00052b878>] arch_timer_handler_phys+0x3c/0x48
|  [<ffffffc00012d078>] handle_percpu_devid_irq+0x100/0x390
|  [<ffffffc000127f34>] generic_handle_irq+0x34/0x4c
|  [<ffffffc000128300>] __handle_domain_irq+0x90/0xf8
|  [<ffffffc000082554>] gic_handle_irq+0x5c/0xa4
|  [<ffffffc0000855ac>] el1_irq+0x6c/0xec
|  [<ffffffc000112bec>] default_idle_call+0x2c/0x44
|  [<ffffffc000113058>] cpu_startup_entry+0x3cc/0x410
|  [<ffffffc0006169f8>] rest_init+0x158/0x168
|  [<ffffffc000888954>] start_kernel+0x3a0/0x3b4
|  [<0000000080621000>] 0x80621000
|irq event stamp: 18723
|hardirqs last  enabled at (18723): [<ffffffc00061c188>] _raw_spin_unlock_irq+0x38/0x80
|hardirqs last disabled at (18722): [<ffffffc000140a4c>] run_hrtimer_softirq+0x2c/0x2f4
|softirqs last  enabled at (0): [<ffffffc0000c4744>] copy_process.isra.50+0x300/0x16d4
|softirqs last disabled at (0): [<          (null)>]           (null)

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
sys-oak pushed a commit that referenced this issue Feb 1, 2019
do_set_cpus_allowed() is not safe vs ->sched_class change.

crash> bt
PID: 11676  TASK: ffff88026f979da0  CPU: 22  COMMAND: "sync_unplug/22"
 #0 [ffff880274d25bc8] machine_kexec at ffffffff8103b41c
 #1 [ffff880274d25c18] crash_kexec at ffffffff810d881a
 #2 [ffff880274d25cd8] oops_end at ffffffff81525818
 #3 [ffff880274d25cf8] do_invalid_op at ffffffff81003096
 #4 [ffff880274d25d90] invalid_op at ffffffff8152d3de
    [exception RIP: set_cpus_allowed_rt+18]
    RIP: ffffffff8109e012  RSP: ffff880274d25e48  RFLAGS: 00010202
    RAX: ffffffff8109e000  RBX: ffff88026f979da0  RCX: ffff8802770cb6e8
    RDX: 0000000000000000  RSI: ffffffff81add700  RDI: ffff88026f979da0
    RBP: ffff880274d25e78   R8: ffffffff816112e0   R9: 0000000000000001
    R10: 0000000000000001  R11: 0000000000011940  R12: ffff88026f979da0
    R13: ffff8802770cb6d0  R14: ffff880274d25fd8  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffff880274d25e60] do_set_cpus_allowed at ffffffff8108e65f
 #6 [ffff880274d25e80] sync_unplug_thread at ffffffff81058c08
 #7 [ffff880274d25ed8] kthread at ffffffff8107cad6
 #8 [ffff880274d25f50] ret_from_fork at ffffffff8152bbbc
crash> task_struct ffff88026f979da0 | grep class
  sched_class = 0xffffffff816111e0 <fair_sched_class+64>,

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
sys-oak pushed a commit that referenced this issue Feb 1, 2019
[    8.014039] BUG: sleeping function called from invalid context at kernel/locking/rtmutex.c:918
[    8.014041] in_atomic(): 0, irqs_disabled(): 1, pid: 78, name: kworker/u4:4
[    8.014045] CPU: 1 PID: 78 Comm: kworker/u4:4 Not tainted 4.1.7-rt7 #5
[    8.014055] Workqueue: events_unbound async_run_entry_fn
[    8.014059]  0000000000000000 ffff880037153748 ffffffff815f32c9 0000000000000002
[    8.014063]  ffff88013a50e380 ffff880037153768 ffffffff815ef075 ffff8800372c06c8
[    8.014066]  ffff8800372c06c8 ffff880037153778 ffffffff8107c0b3 ffff880037153798
[    8.014067] Call Trace:
[    8.014074]  [<ffffffff815f32c9>] dump_stack+0x4a/0x61
[    8.014078]  [<ffffffff815ef075>] ___might_sleep.part.93+0xe9/0xee
[    8.014082]  [<ffffffff8107c0b3>] ___might_sleep+0x53/0x80
[    8.014086]  [<ffffffff815f9064>] rt_spin_lock+0x24/0x50
[    8.014090]  [<ffffffff8109368b>] prepare_to_wait+0x2b/0xa0
[    8.014152]  [<ffffffffa016c04c>] intel_pipe_update_start+0x17c/0x300 [i915]
[    8.014156]  [<ffffffff81093b40>] ? prepare_to_wait_event+0x120/0x120
[    8.014201]  [<ffffffffa0158f36>] intel_begin_crtc_commit+0x166/0x1e0 [i915]
[    8.014215]  [<ffffffffa00c806d>] drm_atomic_helper_commit_planes+0x5d/0x1a0 [drm_kms_helper]
[    8.014260]  [<ffffffffa0171e9b>] intel_atomic_commit+0xab/0xf0 [i915]
[    8.014288]  [<ffffffffa00654c7>] drm_atomic_commit+0x37/0x60 [drm]
[    8.014298]  [<ffffffffa00c6fcd>] drm_atomic_helper_plane_set_property+0x8d/0xd0 [drm_kms_helper]
[    8.014301]  [<ffffffff815f77d9>] ? __ww_mutex_lock+0x39/0x40
[    8.014319]  [<ffffffffa0053b3d>] drm_mode_plane_set_obj_prop+0x2d/0x90 [drm]
[    8.014328]  [<ffffffffa00c8edb>] restore_fbdev_mode+0x6b/0xf0 [drm_kms_helper]
[    8.014337]  [<ffffffffa00cae49>] drm_fb_helper_restore_fbdev_mode_unlocked+0x29/0x80 [drm_kms_helper]
[    8.014346]  [<ffffffffa00caec2>] drm_fb_helper_set_par+0x22/0x50 [drm_kms_helper]
[    8.014390]  [<ffffffffa016dfba>] intel_fbdev_set_par+0x1a/0x60 [i915]
[    8.014394]  [<ffffffff81327dc4>] fbcon_init+0x4f4/0x580
[    8.014398]  [<ffffffff8139ef4c>] visual_init+0xbc/0x120
[    8.014401]  [<ffffffff813a1623>] do_bind_con_driver+0x163/0x330
[    8.014405]  [<ffffffff813a1b2c>] do_take_over_console+0x11c/0x1c0
[    8.014408]  [<ffffffff813236e3>] do_fbcon_takeover+0x63/0xd0
[    8.014410]  [<ffffffff81328965>] fbcon_event_notify+0x785/0x8d0
[    8.014413]  [<ffffffff8107c12d>] ? __might_sleep+0x4d/0x90
[    8.014416]  [<ffffffff810775fe>] notifier_call_chain+0x4e/0x80
[    8.014419]  [<ffffffff810779cd>] __blocking_notifier_call_chain+0x4d/0x70
[    8.014422]  [<ffffffff81077a06>] blocking_notifier_call_chain+0x16/0x20
[    8.014425]  [<ffffffff8132b48b>] fb_notifier_call_chain+0x1b/0x20
[    8.014428]  [<ffffffff8132d8fa>] register_framebuffer+0x21a/0x350
[    8.014439]  [<ffffffffa00cb164>] drm_fb_helper_initial_config+0x274/0x3e0 [drm_kms_helper]
[    8.014483]  [<ffffffffa016f1cb>] intel_fbdev_initial_config+0x1b/0x20 [i915]
[    8.014486]  [<ffffffff8107912c>] async_run_entry_fn+0x4c/0x160
[    8.014490]  [<ffffffff81070ffa>] process_one_work+0x14a/0x470
[    8.014493]  [<ffffffff81071489>] worker_thread+0x169/0x4c0
[    8.014496]  [<ffffffff81071320>] ? process_one_work+0x470/0x470
[    8.014499]  [<ffffffff81076606>] kthread+0xc6/0xe0
[    8.014502]  [<ffffffff81070000>] ? queue_work_on+0x80/0x110
[    8.014506]  [<ffffffff81076540>] ? kthread_worker_fn+0x1c0/0x1c0

Signed-off-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
sys-oak pushed a commit that referenced this issue Feb 20, 2019
[ Upstream commit 6347244 ]

Since __sanitizer_cov_trace_const_cmp4 is marked as notrace, the
function called from __sanitizer_cov_trace_const_cmp4 shouldn't be
traceable either.  ftrace_graph_caller() gets called every time func
write_comp_data() gets called if it isn't marked 'notrace'.  This is the
backtrace from gdb:

 #0  ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:179
 #1  0xffffff8010201920 in ftrace_caller () at ../arch/arm64/kernel/entry-ftrace.S:151
 #2  0xffffff8010439714 in write_comp_data (type=5, arg1=0, arg2=0, ip=18446743524224276596) at ../kernel/kcov.c:116
 #3  0xffffff8010439894 in __sanitizer_cov_trace_const_cmp4 (arg1=<optimized out>, arg2=<optimized out>) at ../kernel/kcov.c:188
 #4  0xffffff8010201874 in prepare_ftrace_return (self_addr=18446743524226602768, parent=0xffffff801014b918, frame_pointer=18446743524223531344) at ./include/generated/atomic-instrumented.h:27
 #5  0xffffff801020194c in ftrace_graph_caller () at ../arch/arm64/kernel/entry-ftrace.S:182

Rework so that write_comp_data() that are called from
__sanitizer_cov_trace_*_cmp*() are marked as 'notrace'.

Commit 903e8ff ("kernel/kcov.c: mark funcs in __sanitizer_cov_trace_pc() as notrace")
missed to mark write_comp_data() as 'notrace'. When that patch was
created gcc-7 was used. In lib/Kconfig.debug
config KCOV_ENABLE_COMPARISONS
	depends on $(cc-option,-fsanitize-coverage=trace-cmp)

That code path isn't hit with gcc-7. However, it were that with gcc-8.

Link: http://lkml.kernel.org/r/20181206143011.23719-1-anders.roxell@linaro.org
Signed-off-by: Anders Roxell <anders.roxell@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Co-developed-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 6, 2019
[ Upstream commit 4ffcbfa ]

KMSAN reported batadv_interface_tx() was possibly using a
garbage value [1]

batadv_get_vid() does have a pskb_may_pull() call
but batadv_interface_tx() does not actually make sure
this did not fail.

[1]
BUG: KMSAN: uninit-value in batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
CPU: 0 PID: 10006 Comm: syz-executor469 Not tainted 4.20.0-rc7+ #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
 __netdev_start_xmit include/linux/netdevice.h:4356 [inline]
 netdev_start_xmit include/linux/netdevice.h:4365 [inline]
 xmit_one net/core/dev.c:3257 [inline]
 dev_hard_start_xmit+0x607/0xc40 net/core/dev.c:3273
 __dev_queue_xmit+0x2e42/0x3bc0 net/core/dev.c:3843
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3876
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x8306/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441889
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdda6fd468 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000441889
RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00007ffdda6fd4c0
R13: 00007ffdda6fd4b0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2759 [inline]
 __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:998 [inline]
 alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5220
 sock_alloc_send_pskb+0xafd/0x10e0 net/core/sock.c:2083
 packet_alloc_skb net/packet/af_packet.c:2781 [inline]
 packet_snd net/packet/af_packet.c:2872 [inline]
 packet_sendmsg+0x661a/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Fixes: c6c8fea ("net: Add batman-adv meshing protocol")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc:	Marek Lindner <mareklindner@neomailbox.ch>
Cc:	Simon Wunderlich <sw@simonwunderlich.de>
Cc:	Antonio Quartulli <a@unstable.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Mar 6, 2019
[ Upstream commit 4ffcbfa ]

KMSAN reported batadv_interface_tx() was possibly using a
garbage value [1]

batadv_get_vid() does have a pskb_may_pull() call
but batadv_interface_tx() does not actually make sure
this did not fail.

[1]
BUG: KMSAN: uninit-value in batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
CPU: 0 PID: 10006 Comm: syz-executor469 Not tainted 4.20.0-rc7+ #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
 __netdev_start_xmit include/linux/netdevice.h:4356 [inline]
 netdev_start_xmit include/linux/netdevice.h:4365 [inline]
 xmit_one net/core/dev.c:3257 [inline]
 dev_hard_start_xmit+0x607/0xc40 net/core/dev.c:3273
 __dev_queue_xmit+0x2e42/0x3bc0 net/core/dev.c:3843
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3876
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x8306/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441889
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdda6fd468 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000441889
RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00007ffdda6fd4c0
R13: 00007ffdda6fd4b0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2759 [inline]
 __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:998 [inline]
 alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5220
 sock_alloc_send_pskb+0xafd/0x10e0 net/core/sock.c:2083
 packet_alloc_skb net/packet/af_packet.c:2781 [inline]
 packet_snd net/packet/af_packet.c:2872 [inline]
 packet_sendmsg+0x661a/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Fixes: c6c8fea ("net: Add batman-adv meshing protocol")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc:	Marek Lindner <mareklindner@neomailbox.ch>
Cc:	Simon Wunderlich <sw@simonwunderlich.de>
Cc:	Antonio Quartulli <a@unstable.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Mar 11, 2019
[ Upstream commit 4ffcbfa ]

KMSAN reported batadv_interface_tx() was possibly using a
garbage value [1]

batadv_get_vid() does have a pskb_may_pull() call
but batadv_interface_tx() does not actually make sure
this did not fail.

[1]
BUG: KMSAN: uninit-value in batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
CPU: 0 PID: 10006 Comm: syz-executor469 Not tainted 4.20.0-rc7+ #5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x173/0x1d0 lib/dump_stack.c:113
 kmsan_report+0x12e/0x2a0 mm/kmsan/kmsan.c:613
 __msan_warning+0x82/0xf0 mm/kmsan/kmsan_instr.c:313
 batadv_interface_tx+0x908/0x1e40 net/batman-adv/soft-interface.c:231
 __netdev_start_xmit include/linux/netdevice.h:4356 [inline]
 netdev_start_xmit include/linux/netdevice.h:4365 [inline]
 xmit_one net/core/dev.c:3257 [inline]
 dev_hard_start_xmit+0x607/0xc40 net/core/dev.c:3273
 __dev_queue_xmit+0x2e42/0x3bc0 net/core/dev.c:3843
 dev_queue_xmit+0x4b/0x60 net/core/dev.c:3876
 packet_snd net/packet/af_packet.c:2928 [inline]
 packet_sendmsg+0x8306/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7
RIP: 0033:0x441889
Code: 18 89 d0 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 bb 10 fc ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007ffdda6fd468 EFLAGS: 00000216 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 0000000000441889
RDX: 000000000000000e RSI: 00000000200000c0 RDI: 0000000000000003
RBP: 0000000000000003 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000216 R12: 00007ffdda6fd4c0
R13: 00007ffdda6fd4b0 R14: 0000000000000000 R15: 0000000000000000

Uninit was created at:
 kmsan_save_stack_with_flags mm/kmsan/kmsan.c:204 [inline]
 kmsan_internal_poison_shadow+0x92/0x150 mm/kmsan/kmsan.c:158
 kmsan_kmalloc+0xa6/0x130 mm/kmsan/kmsan_hooks.c:176
 kmsan_slab_alloc+0xe/0x10 mm/kmsan/kmsan_hooks.c:185
 slab_post_alloc_hook mm/slab.h:446 [inline]
 slab_alloc_node mm/slub.c:2759 [inline]
 __kmalloc_node_track_caller+0xe18/0x1030 mm/slub.c:4383
 __kmalloc_reserve net/core/skbuff.c:137 [inline]
 __alloc_skb+0x309/0xa20 net/core/skbuff.c:205
 alloc_skb include/linux/skbuff.h:998 [inline]
 alloc_skb_with_frags+0x1c7/0xac0 net/core/skbuff.c:5220
 sock_alloc_send_pskb+0xafd/0x10e0 net/core/sock.c:2083
 packet_alloc_skb net/packet/af_packet.c:2781 [inline]
 packet_snd net/packet/af_packet.c:2872 [inline]
 packet_sendmsg+0x661a/0x8f30 net/packet/af_packet.c:2953
 sock_sendmsg_nosec net/socket.c:621 [inline]
 sock_sendmsg net/socket.c:631 [inline]
 __sys_sendto+0x8c4/0xac0 net/socket.c:1788
 __do_sys_sendto net/socket.c:1800 [inline]
 __se_sys_sendto+0x107/0x130 net/socket.c:1796
 __x64_sys_sendto+0x6e/0x90 net/socket.c:1796
 do_syscall_64+0xbc/0xf0 arch/x86/entry/common.c:291
 entry_SYSCALL_64_after_hwframe+0x63/0xe7

Fixes: c6c8fea ("net: Add batman-adv meshing protocol")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc:	Marek Lindner <mareklindner@neomailbox.ch>
Cc:	Simon Wunderlich <sw@simonwunderlich.de>
Cc:	Antonio Quartulli <a@unstable.cc>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jan 22, 2024
commit a8f68b11158f09754418de62e6b3e7b9b7a50cc9 upstream.

Validate next header's offset in ->next_header() so that it isn't
smaller than MID_HEADER_SIZE(server) and then standard_receive3() or
->receive() ends up writing off the end of the buffer because
'pdu_length - MID_HEADER_SIZE(server)' wraps up to a huge length:

  BUG: KASAN: slab-out-of-bounds in _copy_to_iter+0x4fc/0x840
  Write of size 701 at addr ffff88800caf407f by task cifsd/1090

  CPU: 0 PID: 1090 Comm: cifsd Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? _copy_to_iter+0x4fc/0x840
   ? _copy_to_iter+0x4fc/0x840
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   _copy_to_iter+0x4fc/0x840
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? hlock_class+0x32/0xc0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __pfx__copy_to_iter+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_is_held_type+0x90/0x100
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __might_resched+0x278/0x360
   ? __pfx___might_resched+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   __skb_datagram_iter+0x2c2/0x460
   ? __pfx_simple_copy_to_iter+0x10/0x10
   skb_copy_datagram_iter+0x6c/0x110
   tcp_recvmsg_locked+0x9be/0xf40
   ? __pfx_tcp_recvmsg_locked+0x10/0x10
   ? mark_held_locks+0x5d/0x90
   ? srso_alias_return_thunk+0x5/0xfbef5
   tcp_recvmsg+0xe2/0x310
   ? __pfx_tcp_recvmsg+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? lock_acquire+0x14a/0x3a0
   ? srso_alias_return_thunk+0x5/0xfbef5
   inet_recvmsg+0xd0/0x370
   ? __pfx_inet_recvmsg+0x10/0x10
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   sock_recvmsg+0x10d/0x150
   cifs_readv_from_socket+0x25a/0x490 [cifs]
   ? __pfx_cifs_readv_from_socket+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   cifs_read_from_socket+0xb5/0x100 [cifs]
   ? __pfx_cifs_read_from_socket+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? do_raw_spin_trylock+0xd1/0x120
   ? _raw_spin_unlock+0x23/0x40
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __smb2_find_mid+0x126/0x230 [cifs]
   cifs_demultiplex_thread+0xd39/0x1270 [cifs]
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   ? __pfx_lock_release+0x10/0x10
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? mark_held_locks+0x1a/0x90
   ? lockdep_hardirqs_on_prepare+0x136/0x210
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kthread_parkme+0xce/0xf0
   ? __pfx_cifs_demultiplex_thread+0x10/0x10 [cifs]
   kthread+0x18d/0x1d0
   ? kthread+0xdb/0x1d0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x34/0x60
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1b/0x30
   </TASK>

Fixes: 8ce79ec ("cifs: update multiplex loop to handle compounded responses")
Cc: stable@vger.kernel.org
Reported-by: Robert Morris <rtm@csail.mit.edu>
Signed-off-by: Paulo Alcantara (SUSE) <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jan 22, 2024
commit 33eae65c6f49770fec7a662935d4eb4a6406d24b upstream.

A small CIFS buffer (448 bytes) isn't big enough to hold
SMB2_QUERY_INFO request along with user's input data from
CIFS_QUERY_INFO ioctl.  That is, if the user passed an input buffer >
344 bytes, the client will memcpy() off the end of @req->Buffer in
SMB2_query_info_init() thus causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in SMB2_query_info_init+0x242/0x250 [cifs]
  Write of size 1023 at addr ffff88801308c5a8 by task a.out/1240

  CPU: 1 PID: 1240 Comm: a.out Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   SMB2_query_info_init+0x242/0x250 [cifs]
   ? __pfx_SMB2_query_info_init+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? smb_rqst_len+0xa6/0xc0 [cifs]
   smb2_ioctl_query_info+0x4f4/0x9a0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   ? __pfx_cifsConvertToUTF16+0x10/0x10 [cifs]
   ? kasan_set_track+0x25/0x30
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kasan_kmalloc+0x8f/0xa0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? cifs_strndup_to_utf16+0x12d/0x1a0 [cifs]
   ? __build_path_from_dentry_optional_prefix+0x19d/0x2d0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   cifs_ioctl+0x11c7/0x1de0 [cifs]
   ? __pfx_cifs_ioctl+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? rcu_is_watching+0x23/0x50
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __rseq_handle_notify_resume+0x6cd/0x850
   ? __pfx___schedule+0x10/0x10
   ? blkcg_iostat_update+0x250/0x290
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? ksys_write+0xe9/0x170
   __x64_sys_ioctl+0xc9/0x100
   do_syscall_64+0x47/0xf0
   entry_SYSCALL_64_after_hwframe+0x6f/0x77
  RIP: 0033:0x7f893dde49cf
  Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48
  89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89>
  c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00
  RSP: 002b:00007ffc03ff4160 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00007ffc03ff4378 RCX: 00007f893dde49cf
  RDX: 00007ffc03ff41d0 RSI: 00000000c018cf07 RDI: 0000000000000003
  RBP: 00007ffc03ff4260 R08: 0000000000000410 R09: 0000000000000001
  R10: 00007f893dce7300 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffc03ff4388 R14: 00007f893df15000 R15: 0000000000406de0
   </TASK>

Fix this by increasing size of SMB2_QUERY_INFO request buffers and
validating input length to prevent other callers from overflowing @Req
in SMB2_query_info_init() as well.

Fixes: f5b05d6 ("cifs: add IOCTL for QUERY_INFO passthrough to userspace")
Cc: stable@vger.kernel.org
Reported-by: Robert Morris <rtm@csail.mit.edu>
Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jan 30, 2024
[ Upstream commit 14694179e561b5f2f7e56a0f590e2cb49a9cc7ab ]

Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep
warning:

 ============================================
 WARNING: possible recursive locking detected
 6.7.0-rc5-wt+ #532 Not tainted
 --------------------------------------------
 sh/92 is trying to acquire lock:
 c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 but task is already holding lock:
 c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&irq_desc_lock_class);
   lock(&irq_desc_lock_class);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 6 locks held by sh/92:
  #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178
  #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284
  #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284
  #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8
  #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c
  #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 stack backtrace:
 CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ #532
 Hardware name: Atmel SAMA5
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x34/0x48
  dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c
  __lock_acquire from lock_acquire.part.0+0x124/0x2d0
  lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78
  _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100
  __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204
  irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4
  atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204
  irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8
  gpio_keys_suspend from dpm_run_callback+0xe4/0x248
  dpm_run_callback from __device_suspend+0x234/0x91c
  __device_suspend from dpm_suspend+0x224/0x43c
  dpm_suspend from dpm_suspend_start+0x9c/0xa8
  dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84
  suspend_devices_and_enter from pm_suspend+0x460/0x4e8
  pm_suspend from state_store+0x78/0xe4
  state_store from kernfs_fop_write_iter+0x1a0/0x284
  kernfs_fop_write_iter from vfs_write+0x38c/0x6f4
  vfs_write from ksys_write+0xd8/0x178
  ksys_write from ret_fast_syscall+0x0/0x1c
 Exception stack(0xc52b3fa8 to 0xc52b3ff0)
 3fa0:                   00000004 005a0ae8 00000001 005a0ae8 00000004 00000001
 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190
 3fe0: 00000004 b6c61678 aec5a041 aebf1a26

This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever
a wake up source configures an IRQ through irq_set_irq_wake, it will
lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent"
IRQ which will do the same on its own IRQ desc, but since those two locks
share the same class, lockdep reports this as an issue.

Fix lockdep false positive by setting a different class for parent and
children IRQ

Fixes: 7761808 ("pinctrl: introduce driver for Atmel PIO4 controller")
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Link: https://lore.kernel.org/r/20231215-lockdep_warning-v1-1-8137b2510ed5@bootlin.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Feb 2, 2024
commit d8b90d600aff181936457f032d116dbd8534db06 upstream.

When scanning namespaces, it is possible to get valid data from the first
call to nvme_identify_ns() in nvme_alloc_ns(), but not from the second
call in nvme_update_ns_info_block().  In particular, if the NSID becomes
inactive between the two commands, a storage device may return a buffer
filled with zero as per 4.1.5.1.  In this case, we can get a kernel crash
due to a divide-by-zero in blk_stack_limits() because ns->lba_shift will
be set to zero.

PID: 326      TASK: ffff95fec3cd8000  CPU: 29   COMMAND: "kworker/u98:10"
 #0 [ffffad8f8702f9e0] machine_kexec at ffffffff91c76ec7
 #1 [ffffad8f8702fa38] __crash_kexec at ffffffff91dea4fa
 #2 [ffffad8f8702faf8] crash_kexec at ffffffff91deb788
 #3 [ffffad8f8702fb00] oops_end at ffffffff91c2e4bb
 #4 [ffffad8f8702fb20] do_trap at ffffffff91c2a4ce
 #5 [ffffad8f8702fb70] do_error_trap at ffffffff91c2a595
 #6 [ffffad8f8702fbb0] exc_divide_error at ffffffff928506e6
 #7 [ffffad8f8702fbd0] asm_exc_divide_error at ffffffff92a00926
    [exception RIP: blk_stack_limits+434]
    RIP: ffffffff92191872  RSP: ffffad8f8702fc80  RFLAGS: 00010246
    RAX: 0000000000000000  RBX: ffff95efa0c91800  RCX: 0000000000000001
    RDX: 0000000000000000  RSI: 0000000000000001  RDI: 0000000000000001
    RBP: 00000000ffffffff   R8: ffff95fec7df35a8   R9: 0000000000000000
    R10: 0000000000000000  R11: 0000000000000001  R12: 0000000000000000
    R13: 0000000000000000  R14: 0000000000000000  R15: ffff95fed33c09a8
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffad8f8702fce0] nvme_update_ns_info_block at ffffffffc06d3533 [nvme_core]
 #9 [ffffad8f8702fd18] nvme_scan_ns at ffffffffc06d6fa7 [nvme_core]

This happened when the check for valid data was moved out of nvme_identify_ns()
into one of the callers.  Fix this by checking in both callers.

Link: https://bugzilla.kernel.org/show_bug.cgi?id=218186
Fixes: 0dd6fff ("nvme: bring back auto-removal of deleted namespaces during sequential scan")
Cc: stable@vger.kernel.org
Signed-off-by: Ewan D. Milne <emilne@redhat.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Feb 2, 2024
[ Upstream commit e3e82fcb79eeb3f1a88a89f676831773caff514a ]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn
Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com>
Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn>
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Feb 2, 2024
commit c312828c37a72fe2d033a961c47c227b0767e9f8 upstream.

bpf_cgroup_from_id() is basically a wrapper to cgroup_get_from_id(),
that is relying on kernfs to determine the right cgroup associated to
the target id.

As a kfunc, it has the potential to be attached to any function through
BPF, particularly in contexts where certain locks are held.

However, kernfs is not using an irq safe spinlock for kernfs_idr_lock,
that means any kernfs function that is acquiring this lock can be
interrupted and potentially hit bpf_cgroup_from_id() in the process,
triggering a deadlock.

For example, it is really easy to trigger a lockdep splat between
kernfs_idr_lock and rq->_lock, attaching a small BPF program to
__set_cpus_allowed_ptr_locked() that just calls bpf_cgroup_from_id():

 =====================================================
 WARNING: HARDIRQ-safe -> HARDIRQ-unsafe lock order detected
 6.7.0-rc7-virtme #5 Not tainted
 -----------------------------------------------------
 repro/131 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
 ffffffffb2dc4578 (kernfs_idr_lock){+.+.}-{2:2}, at: kernfs_find_and_get_node_by_id+0x1d/0x80

 and this task is already holding:
 ffff911cbecaf218 (&rq->__lock){-.-.}-{2:2}, at: task_rq_lock+0x50/0xc0
 which would create a new lock dependency:
  (&rq->__lock){-.-.}-{2:2} -> (kernfs_idr_lock){+.+.}-{2:2}

 but this new dependency connects a HARDIRQ-irq-safe lock:
  (&rq->__lock){-.-.}-{2:2}

 ... which became HARDIRQ-irq-safe at:
   lock_acquire+0xbf/0x2b0
   _raw_spin_lock_nested+0x2e/0x40
   scheduler_tick+0x5d/0x170
   update_process_times+0x9c/0xb0
   tick_periodic+0x27/0xe0
   tick_handle_periodic+0x24/0x70
   __sysvec_apic_timer_interrupt+0x64/0x1a0
   sysvec_apic_timer_interrupt+0x6f/0x80
   asm_sysvec_apic_timer_interrupt+0x1a/0x20
   memcpy+0xc/0x20
   arch_dup_task_struct+0x15/0x30
   copy_process+0x1ce/0x1eb0
   kernel_clone+0xac/0x390
   kernel_thread+0x6f/0xa0
   kthreadd+0x199/0x230
   ret_from_fork+0x31/0x50
   ret_from_fork_asm+0x1b/0x30

 to a HARDIRQ-irq-unsafe lock:
  (kernfs_idr_lock){+.+.}-{2:2}

 ... which became HARDIRQ-irq-unsafe at:
 ...
   lock_acquire+0xbf/0x2b0
   _raw_spin_lock+0x30/0x40
   __kernfs_new_node.isra.0+0x83/0x280
   kernfs_create_root+0xf6/0x1d0
   sysfs_init+0x1b/0x70
   mnt_init+0xd9/0x2a0
   vfs_caches_init+0xcf/0xe0
   start_kernel+0x58a/0x6a0
   x86_64_start_reservations+0x18/0x30
   x86_64_start_kernel+0xc5/0xe0
   secondary_startup_64_no_verify+0x178/0x17b

 other info that might help us debug this:

  Possible interrupt unsafe locking scenario:

        CPU0                    CPU1
        ----                    ----
   lock(kernfs_idr_lock);
                                local_irq_disable();
                                lock(&rq->__lock);
                                lock(kernfs_idr_lock);
   <Interrupt>
     lock(&rq->__lock);

  *** DEADLOCK ***

Prevent this deadlock condition converting kernfs_idr_lock to a raw irq
safe spinlock.

The performance impact of this change should be negligible and it also
helps to prevent similar deadlock conditions with any other subsystems
that may depend on kernfs.

Fixes: 332ea1f ("bpf: Add bpf_cgroup_from_id() kfunc")
Cc: stable <stable@kernel.org>
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Acked-by: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20231229074916.53547-1-andrea.righi@canonical.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Mar 8, 2024
[ Upstream commit e3e82fcb79eeb3f1a88a89f676831773caff514a ]

When creating ceq_0 during probing irdma, cqp.sc_cqp will be sent as a
cqp_request to cqp->sc_cqp.sq_ring. If the request is pending when
removing the irdma driver or unplugging its aux device, cqp.sc_cqp will be
dereferenced as wrong struct in irdma_free_pending_cqp_request().

  PID: 3669   TASK: ffff88aef892c000  CPU: 28  COMMAND: "kworker/28:0"
   #0 [fffffe0000549e38] crash_nmi_callback at ffffffff810e3a34
   #1 [fffffe0000549e40] nmi_handle at ffffffff810788b2
   #2 [fffffe0000549ea0] default_do_nmi at ffffffff8107938f
   #3 [fffffe0000549eb8] do_nmi at ffffffff81079582
   #4 [fffffe0000549ef0] end_repeat_nmi at ffffffff82e016b4
      [exception RIP: native_queued_spin_lock_slowpath+1291]
      RIP: ffffffff8127e72b  RSP: ffff88aa841ef778  RFLAGS: 00000046
      RAX: 0000000000000000  RBX: ffff88b01f849700  RCX: ffffffff8127e47e
      RDX: 0000000000000000  RSI: 0000000000000004  RDI: ffffffff83857ec0
      RBP: ffff88afe3e4efc8   R8: ffffed15fc7c9dfa   R9: ffffed15fc7c9dfa
      R10: 0000000000000001  R11: ffffed15fc7c9df9  R12: 0000000000740000
      R13: ffff88b01f849708  R14: 0000000000000003  R15: ffffed1603f092e1
      ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0000
  -- <NMI exception stack> --
   #5 [ffff88aa841ef778] native_queued_spin_lock_slowpath at ffffffff8127e72b
   #6 [ffff88aa841ef7b0] _raw_spin_lock_irqsave at ffffffff82c22aa4
   #7 [ffff88aa841ef7c8] __wake_up_common_lock at ffffffff81257363
   #8 [ffff88aa841ef888] irdma_free_pending_cqp_request at ffffffffa0ba12cc [irdma]
   #9 [ffff88aa841ef958] irdma_cleanup_pending_cqp_op at ffffffffa0ba1469 [irdma]
   #10 [ffff88aa841ef9c0] irdma_ctrl_deinit_hw at ffffffffa0b2989f [irdma]
   #11 [ffff88aa841efa28] irdma_remove at ffffffffa0b252df [irdma]
   #12 [ffff88aa841efae8] auxiliary_bus_remove at ffffffff8219afdb
   #13 [ffff88aa841efb00] device_release_driver_internal at ffffffff821882e6
   #14 [ffff88aa841efb38] bus_remove_device at ffffffff82184278
   #15 [ffff88aa841efb88] device_del at ffffffff82179d23
   #16 [ffff88aa841efc48] ice_unplug_aux_dev at ffffffffa0eb1c14 [ice]
   #17 [ffff88aa841efc68] ice_service_task at ffffffffa0d88201 [ice]
   #18 [ffff88aa841efde8] process_one_work at ffffffff811c589a
   #19 [ffff88aa841efe60] worker_thread at ffffffff811c71ff
   #20 [ffff88aa841eff10] kthread at ffffffff811d87a0
   #21 [ffff88aa841eff50] ret_from_fork at ffffffff82e0022f

Fixes: 44d9e52 ("RDMA/irdma: Implement device initialization definitions")
Link: https://lore.kernel.org/r/20231130081415.891006-1-lishifeng@sangfor.com.cn
Suggested-by: "Ismail, Mustafa" <mustafa.ismail@intel.com>
Signed-off-by: Shifeng Li <lishifeng@sangfor.com.cn>
Reviewed-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 8, 2024
[ Upstream commit 14694179e561b5f2f7e56a0f590e2cb49a9cc7ab ]

Trying to suspend to RAM on SAMA5D27 EVK leads to the following lockdep
warning:

 ============================================
 WARNING: possible recursive locking detected
 6.7.0-rc5-wt+ #532 Not tainted
 --------------------------------------------
 sh/92 is trying to acquire lock:
 c3cf306c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 but task is already holding lock:
 c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 other info that might help us debug this:
  Possible unsafe locking scenario:

        CPU0
        ----
   lock(&irq_desc_lock_class);
   lock(&irq_desc_lock_class);

  *** DEADLOCK ***

  May be due to missing lock nesting notation

 6 locks held by sh/92:
  #0: c3aa0258 (sb_writers#6){.+.+}-{0:0}, at: ksys_write+0xd8/0x178
  #1: c4c2df44 (&of->mutex){+.+.}-{3:3}, at: kernfs_fop_write_iter+0x138/0x284
  #2: c32684a0 (kn->active){.+.+}-{0:0}, at: kernfs_fop_write_iter+0x148/0x284
  #3: c232b6d4 (system_transition_mutex){+.+.}-{3:3}, at: pm_suspend+0x13c/0x4e8
  #4: c387b088 (&dev->mutex){....}-{3:3}, at: __device_suspend+0x1e8/0x91c
  #5: c3d7c46c (&irq_desc_lock_class){-.-.}-{2:2}, at: __irq_get_desc_lock+0xe8/0x100

 stack backtrace:
 CPU: 0 PID: 92 Comm: sh Not tainted 6.7.0-rc5-wt+ #532
 Hardware name: Atmel SAMA5
  unwind_backtrace from show_stack+0x18/0x1c
  show_stack from dump_stack_lvl+0x34/0x48
  dump_stack_lvl from __lock_acquire+0x19ec/0x3a0c
  __lock_acquire from lock_acquire.part.0+0x124/0x2d0
  lock_acquire.part.0 from _raw_spin_lock_irqsave+0x5c/0x78
  _raw_spin_lock_irqsave from __irq_get_desc_lock+0xe8/0x100
  __irq_get_desc_lock from irq_set_irq_wake+0xa8/0x204
  irq_set_irq_wake from atmel_gpio_irq_set_wake+0x58/0xb4
  atmel_gpio_irq_set_wake from irq_set_irq_wake+0x100/0x204
  irq_set_irq_wake from gpio_keys_suspend+0xec/0x2b8
  gpio_keys_suspend from dpm_run_callback+0xe4/0x248
  dpm_run_callback from __device_suspend+0x234/0x91c
  __device_suspend from dpm_suspend+0x224/0x43c
  dpm_suspend from dpm_suspend_start+0x9c/0xa8
  dpm_suspend_start from suspend_devices_and_enter+0x1e0/0xa84
  suspend_devices_and_enter from pm_suspend+0x460/0x4e8
  pm_suspend from state_store+0x78/0xe4
  state_store from kernfs_fop_write_iter+0x1a0/0x284
  kernfs_fop_write_iter from vfs_write+0x38c/0x6f4
  vfs_write from ksys_write+0xd8/0x178
  ksys_write from ret_fast_syscall+0x0/0x1c
 Exception stack(0xc52b3fa8 to 0xc52b3ff0)
 3fa0:                   00000004 005a0ae8 00000001 005a0ae8 00000004 00000001
 3fc0: 00000004 005a0ae8 00000001 00000004 00000004 b6c616c0 00000020 0059d190
 3fe0: 00000004 b6c61678 aec5a041 aebf1a26

This warning is raised because pinctrl-at91-pio4 uses chained IRQ. Whenever
a wake up source configures an IRQ through irq_set_irq_wake, it will
lock the corresponding IRQ desc, and then call irq_set_irq_wake on "parent"
IRQ which will do the same on its own IRQ desc, but since those two locks
share the same class, lockdep reports this as an issue.

Fix lockdep false positive by setting a different class for parent and
children IRQ

Fixes: 7761808 ("pinctrl: introduce driver for Atmel PIO4 controller")
Signed-off-by: Alexis Lothoré <alexis.lothore@bootlin.com>
Link: https://lore.kernel.org/r/20231215-lockdep_warning-v1-1-8137b2510ed5@bootlin.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 8, 2024
[ Upstream commit 33eae65c6f49770fec7a662935d4eb4a6406d24b ]

A small CIFS buffer (448 bytes) isn't big enough to hold
SMB2_QUERY_INFO request along with user's input data from
CIFS_QUERY_INFO ioctl.  That is, if the user passed an input buffer >
344 bytes, the client will memcpy() off the end of @req->Buffer in
SMB2_query_info_init() thus causing the following KASAN splat:

  BUG: KASAN: slab-out-of-bounds in SMB2_query_info_init+0x242/0x250 [cifs]
  Write of size 1023 at addr ffff88801308c5a8 by task a.out/1240

  CPU: 1 PID: 1240 Comm: a.out Not tainted 6.7.0-rc4 #5
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
  rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014
  Call Trace:
   <TASK>
   dump_stack_lvl+0x4a/0x80
   print_report+0xcf/0x650
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __phys_addr+0x46/0x90
   kasan_report+0xd8/0x110
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   ? SMB2_query_info_init+0x242/0x250 [cifs]
   kasan_check_range+0x105/0x1b0
   __asan_memcpy+0x3c/0x60
   SMB2_query_info_init+0x242/0x250 [cifs]
   ? __pfx_SMB2_query_info_init+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? smb_rqst_len+0xa6/0xc0 [cifs]
   smb2_ioctl_query_info+0x4f4/0x9a0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   ? __pfx_cifsConvertToUTF16+0x10/0x10 [cifs]
   ? kasan_set_track+0x25/0x30
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __kasan_kmalloc+0x8f/0xa0
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? cifs_strndup_to_utf16+0x12d/0x1a0 [cifs]
   ? __build_path_from_dentry_optional_prefix+0x19d/0x2d0 [cifs]
   ? __pfx_smb2_ioctl_query_info+0x10/0x10 [cifs]
   cifs_ioctl+0x11c7/0x1de0 [cifs]
   ? __pfx_cifs_ioctl+0x10/0x10 [cifs]
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? rcu_is_watching+0x23/0x50
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? __rseq_handle_notify_resume+0x6cd/0x850
   ? __pfx___schedule+0x10/0x10
   ? blkcg_iostat_update+0x250/0x290
   ? srso_alias_return_thunk+0x5/0xfbef5
   ? ksys_write+0xe9/0x170
   __x64_sys_ioctl+0xc9/0x100
   do_syscall_64+0x47/0xf0
   entry_SYSCALL_64_after_hwframe+0x6f/0x77
  RIP: 0033:0x7f893dde49cf
  Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48
  89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89>
  c2 3d 00 f0 ff ff 77 18 48 8b 44 24 18 64 48 2b 04 25 28 00 00
  RSP: 002b:00007ffc03ff4160 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
  RAX: ffffffffffffffda RBX: 00007ffc03ff4378 RCX: 00007f893dde49cf
  RDX: 00007ffc03ff41d0 RSI: 00000000c018cf07 RDI: 0000000000000003
  RBP: 00007ffc03ff4260 R08: 0000000000000410 R09: 0000000000000001
  R10: 00007f893dce7300 R11: 0000000000000246 R12: 0000000000000000
  R13: 00007ffc03ff4388 R14: 00007f893df15000 R15: 0000000000406de0
   </TASK>

Fix this by increasing size of SMB2_QUERY_INFO request buffers and
validating input length to prevent other callers from overflowing @Req
in SMB2_query_info_init() as well.

Fixes: f5b05d6 ("cifs: add IOCTL for QUERY_INFO passthrough to userspace")
Cc: stable@vger.kernel.org
Reported-by: Robert Morris <rtm@csail.mit.edu>
Signed-off-by: Paulo Alcantara <pc@manguebit.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 8, 2024
Upstream commit bac1ec5 ("usb: xhci: Set quirk for
XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI
which fixes XHC timeout, which was seen on synopsys XHCs while
using SG buffers. But the support for this quirk isn't present
in the DWC3 layer.

We will encounter this XHCI timeout/hung issue if we run iperf
loopback tests using RTL8156 ethernet adaptor on DWC3 targets
with scatter-gather enabled. This gets resolved after enabling
the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using
the xhci device property since its needed for DWC3 controller.

In Synopsys DWC3 databook,
Table 9-3: xHCI Debug Capability Limitations
Chained TRBs greater than TRB cache size: The debug capability
driver must not create a multi-TRB TD that describes smaller
than a 1K packet that spreads across 8 or more TRBs on either
the IN TR or the OUT TR.

Cc: stable@vger.kernel.org #5.11
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Bug: 322910830
(cherry picked from commit 817349b6d26aadd8b38283a05ce0bab106b4c765
https: //git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git/ usb-linus)
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Change-Id: I9a5bf2c4d43551406d452927084576387656953d
sys-oak pushed a commit that referenced this issue Mar 13, 2024
[ Upstream commit fc3a5534e2a8855427403113cbeb54af5837bbe0 ]

An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang <zhangmingyi5@huawei.com>
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Changye Wu <wuchangye@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 13, 2024
commit 817349b6d26aadd8b38283a05ce0bab106b4c765 upstream.

Upstream commit bac1ec5 ("usb: xhci: Set quirk for
XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI
which fixes XHC timeout, which was seen on synopsys XHCs while
using SG buffers. But the support for this quirk isn't present
in the DWC3 layer.

We will encounter this XHCI timeout/hung issue if we run iperf
loopback tests using RTL8156 ethernet adaptor on DWC3 targets
with scatter-gather enabled. This gets resolved after enabling
the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using
the xhci device property since its needed for DWC3 controller.

In Synopsys DWC3 databook,
Table 9-3: xHCI Debug Capability Limitations
Chained TRBs greater than TRB cache size: The debug capability
driver must not create a multi-TRB TD that describes smaller
than a 1K packet that spreads across 8 or more TRBs on either
the IN TR or the OUT TR.

Cc: stable@vger.kernel.org #5.11
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Mar 18, 2024
[ Upstream commit fc3a5534e2a8855427403113cbeb54af5837bbe0 ]

An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang <zhangmingyi5@huawei.com>
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Changye Wu <wuchangye@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 25, 2024
[ Upstream commit d3ea125df37dc37972d581b74a5d3785c3f283ab ]

If CONFIG_HARDENED_USERCOPY is enabled, copying completion record from
event log cache to user triggers a kernel bug.

[ 1987.159822] usercopy: Kernel memory exposure attempt detected from SLUB object 'dsa0' (offset 74, size 31)!
[ 1987.170845] ------------[ cut here ]------------
[ 1987.176086] kernel BUG at mm/usercopy.c:102!
[ 1987.180946] invalid opcode: 0000 [#1] PREEMPT SMP NOPTI
[ 1987.186866] CPU: 17 PID: 528 Comm: kworker/17:1 Not tainted 6.8.0-rc2+ #5
[ 1987.194537] Hardware name: Intel Corporation AvenueCity/AvenueCity, BIOS BHSDCRB1.86B.2492.D03.2307181620 07/18/2023
[ 1987.206405] Workqueue: wq0.0 idxd_evl_fault_work [idxd]
[ 1987.212338] RIP: 0010:usercopy_abort+0x72/0x90
[ 1987.217381] Code: 58 65 9c 50 48 c7 c2 17 85 61 9c 57 48 c7 c7 98 fd 6b 9c 48 0f 44 d6 48 c7 c6 b3 08 62 9c 4c 89 d1 49 0f 44 f3 e8 1e 2e d5 ff <0f> 0b 49 c7 c1 9e 42 61 9c 4c 89 cf 4d 89 c8 eb a9 66 66 2e 0f 1f
[ 1987.238505] RSP: 0018:ff62f5cf20607d60 EFLAGS: 00010246
[ 1987.244423] RAX: 000000000000005f RBX: 000000000000001f RCX: 0000000000000000
[ 1987.252480] RDX: 0000000000000000 RSI: ffffffff9c61429e RDI: 00000000ffffffff
[ 1987.260538] RBP: ff62f5cf20607d78 R08: ff2a6a89ef3fffe8 R09: 00000000fffeffff
[ 1987.268595] R10: ff2a6a89eed00000 R11: 0000000000000003 R12: ff2a66934849c89a
[ 1987.276652] R13: 0000000000000001 R14: ff2a66934849c8b9 R15: ff2a66934849c899
[ 1987.284710] FS:  0000000000000000(0000) GS:ff2a66b22fe40000(0000) knlGS:0000000000000000
[ 1987.293850] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 1987.300355] CR2: 00007fe291a37000 CR3: 000000010fbd4005 CR4: 0000000000f71ef0
[ 1987.308413] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 1987.316470] DR3: 0000000000000000 DR6: 00000000fffe07f0 DR7: 0000000000000400
[ 1987.324527] PKRU: 55555554
[ 1987.327622] Call Trace:
[ 1987.330424]  <TASK>
[ 1987.332826]  ? show_regs+0x6e/0x80
[ 1987.336703]  ? die+0x3c/0xa0
[ 1987.339988]  ? do_trap+0xd4/0xf0
[ 1987.343662]  ? do_error_trap+0x75/0xa0
[ 1987.347922]  ? usercopy_abort+0x72/0x90
[ 1987.352277]  ? exc_invalid_op+0x57/0x80
[ 1987.356634]  ? usercopy_abort+0x72/0x90
[ 1987.360988]  ? asm_exc_invalid_op+0x1f/0x30
[ 1987.365734]  ? usercopy_abort+0x72/0x90
[ 1987.370088]  __check_heap_object+0xb7/0xd0
[ 1987.374739]  __check_object_size+0x175/0x2d0
[ 1987.379588]  idxd_copy_cr+0xa9/0x130 [idxd]
[ 1987.384341]  idxd_evl_fault_work+0x127/0x390 [idxd]
[ 1987.389878]  process_one_work+0x13e/0x300
[ 1987.394435]  ? __pfx_worker_thread+0x10/0x10
[ 1987.399284]  worker_thread+0x2f7/0x420
[ 1987.403544]  ? _raw_spin_unlock_irqrestore+0x2b/0x50
[ 1987.409171]  ? __pfx_worker_thread+0x10/0x10
[ 1987.414019]  kthread+0x107/0x140
[ 1987.417693]  ? __pfx_kthread+0x10/0x10
[ 1987.421954]  ret_from_fork+0x3d/0x60
[ 1987.426019]  ? __pfx_kthread+0x10/0x10
[ 1987.430281]  ret_from_fork_asm+0x1b/0x30
[ 1987.434744]  </TASK>

The issue arises because event log cache is created using
kmem_cache_create() which is not suitable for user copy.

Fix the issue by creating event log cache with
kmem_cache_create_usercopy(), ensuring safe user copy.

Fixes: c2f156b ("dmaengine: idxd: create kmem cache for event log fault items")
Reported-by: Tony Zhu <tony.zhu@intel.com>
Tested-by: Tony Zhu <tony.zhu@intel.com>
Signed-off-by: Fenghua Yu <fenghua.yu@intel.com>
Reviewed-by: Lijun Pan <lijun.pan@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Link: https://lore.kernel.org/r/20240209191412.1050270-1-fenghua.yu@intel.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Mar 26, 2024
commit 817349b6d26aadd8b38283a05ce0bab106b4c765 upstream.

Upstream commit bac1ec5 ("usb: xhci: Set quirk for
XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI
which fixes XHC timeout, which was seen on synopsys XHCs while
using SG buffers. But the support for this quirk isn't present
in the DWC3 layer.

We will encounter this XHCI timeout/hung issue if we run iperf
loopback tests using RTL8156 ethernet adaptor on DWC3 targets
with scatter-gather enabled. This gets resolved after enabling
the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using
the xhci device property since its needed for DWC3 controller.

In Synopsys DWC3 databook,
Table 9-3: xHCI Debug Capability Limitations
Chained TRBs greater than TRB cache size: The debug capability
driver must not create a multi-TRB TD that describes smaller
than a 1K packet that spreads across 8 or more TRBs on either
the IN TR or the OUT TR.

Cc: stable@vger.kernel.org #5.11
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Apr 18, 2024
…pty list

[ Upstream commit 55b6c738673871c9b0edae05d0c97995c1ff08c4 ]

If all peers are removed via wg_peer_remove_all(), rather than setting
peer_list to empty, the peer is added to a temporary list with a head on
the stack of wg_peer_remove_all(). If a netlink dump is resumed and the
cursored peer is one that has been removed via wg_peer_remove_all(), it
will iterate from that peer and then attempt to dump freed peers.

Fix this by instead checking peer->is_dead, which was explictly created
for this purpose. Also move up the device_update_lock lockdep assertion,
since reading is_dead relies on that.

It can be reproduced by a small script like:

    echo "Setting config..."
    ip link add dev wg0 type wireguard
    wg setconf wg0 /big-config
    (
            while true; do
                    echo "Showing config..."
                    wg showconf wg0 > /dev/null
            done
    ) &
    sleep 4
    wg setconf wg0 <(printf "[Peer]\nPublicKey=$(wg genkey)\n")

Resulting in:

    BUG: KASAN: slab-use-after-free in __lock_acquire+0x182a/0x1b20
    Read of size 8 at addr ffff88811956ec70 by task wg/59
    CPU: 2 PID: 59 Comm: wg Not tainted 6.8.0-rc2-debug+ #5
    Call Trace:
     <TASK>
     dump_stack_lvl+0x47/0x70
     print_address_description.constprop.0+0x2c/0x380
     print_report+0xab/0x250
     kasan_report+0xba/0xf0
     __lock_acquire+0x182a/0x1b20
     lock_acquire+0x191/0x4b0
     down_read+0x80/0x440
     get_peer+0x140/0xcb0
     wg_get_device_dump+0x471/0x1130

Cc: stable@vger.kernel.org
Fixes: e7096c1 ("net: WireGuard secure network tunnel")
Reported-by: Lillian Berry <lillian@star-ark.net>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Apr 18, 2024
commit 4be9075fec0a639384ed19975634b662bfab938f upstream.

The driver creates /sys/kernel/debug/dri/0/mob_ttm even when the
corresponding ttm_resource_manager is not allocated.
This leads to a crash when trying to read from this file.

Add a check to create mob_ttm, system_mob_ttm, and gmr_ttm debug file
only when the corresponding ttm_resource_manager is allocated.

crash> bt
PID: 3133409  TASK: ffff8fe4834a5000  CPU: 3    COMMAND: "grep"
 #0 [ffffb954506b3b20] machine_kexec at ffffffffb2a6bec3
 #1 [ffffb954506b3b78] __crash_kexec at ffffffffb2bb598a
 #2 [ffffb954506b3c38] crash_kexec at ffffffffb2bb68c1
 #3 [ffffb954506b3c50] oops_end at ffffffffb2a2a9b1
 #4 [ffffb954506b3c70] no_context at ffffffffb2a7e913
 #5 [ffffb954506b3cc8] __bad_area_nosemaphore at ffffffffb2a7ec8c
 #6 [ffffb954506b3d10] do_page_fault at ffffffffb2a7f887
 #7 [ffffb954506b3d40] page_fault at ffffffffb360116e
    [exception RIP: ttm_resource_manager_debug+0x11]
    RIP: ffffffffc04afd11  RSP: ffffb954506b3df0  RFLAGS: 00010246
    RAX: ffff8fe41a6d1200  RBX: 0000000000000000  RCX: 0000000000000940
    RDX: 0000000000000000  RSI: ffffffffc04b4338  RDI: 0000000000000000
    RBP: ffffb954506b3e08   R8: ffff8fee3ffad000   R9: 0000000000000000
    R10: ffff8fe41a76a000  R11: 0000000000000001  R12: 00000000ffffffff
    R13: 0000000000000001  R14: ffff8fe5bb6f3900  R15: ffff8fe41a6d1200
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #8 [ffffb954506b3e00] ttm_resource_manager_show at ffffffffc04afde7 [ttm]
 #9 [ffffb954506b3e30] seq_read at ffffffffb2d8f9f3
    RIP: 00007f4c4eda8985  RSP: 00007ffdbba9e9f8  RFLAGS: 00000246
    RAX: ffffffffffffffda  RBX: 000000000037e000  RCX: 00007f4c4eda8985
    RDX: 000000000037e000  RSI: 00007f4c41573000  RDI: 0000000000000003
    RBP: 000000000037e000   R8: 0000000000000000   R9: 000000000037fe30
    R10: 0000000000000000  R11: 0000000000000246  R12: 00007f4c41573000
    R13: 0000000000000003  R14: 00007f4c41572010  R15: 0000000000000003
    ORIG_RAX: 0000000000000000  CS: 0033  SS: 002b

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Fixes: af4a25b ("drm/vmwgfx: Add debugfs entries for various ttm resource managers")
Cc: <stable@vger.kernel.org>
Reviewed-by: Zack Rusin <zack.rusin@broadcom.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240312093551.196609-1-jfalempe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
[ Upstream commit 0bef512012b1cd8820f0c9ec80e5f8ceb43fdd59 ]

Based on a syzbot report, it appears many virtual
drivers do not yet use netdev_lockdep_set_classes(),
triggerring lockdep false positives.

WARNING: possible recursive locking detected
6.8.0-rc4-next-20240212-syzkaller #0 Not tainted

syz-executor.0/19016 is trying to acquire lock:
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880162cb298 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

but task is already holding lock:
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
 ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
  lock(_xmit_ETHER#2);
  lock(_xmit_ETHER#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

9 locks held by syz-executor.0/19016:
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
  #0: ffffffff8f385208 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x82c/0x1040 net/core/rtnetlink.c:6603
  #1: ffffc90000a08c00 ((&in_dev->mr_ifc_timer)){+.-.}-{0:0}, at: call_timer_fn+0xc0/0x600 kernel/time/timer.c:1697
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #2: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #3: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #4: ffff8880416e3258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: spin_lock include/linux/spinlock.h:351 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  #5: ffff8880223db4d8 (_xmit_ETHER#2){+.-.}-{2:2}, at: sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
  #6: ffffffff8e131520 (rcu_read_lock){....}-{1:2}, at: ip_finish_output2+0x45f/0x1360 net/ipv4/ip_output.c:228
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: local_bh_disable include/linux/bottom_half.h:20 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: rcu_read_lock_bh include/linux/rcupdate.h:802 [inline]
  #7: ffffffff8e131580 (rcu_read_lock_bh){....}-{1:2}, at: __dev_queue_xmit+0x2c4/0x3b10 net/core/dev.c:4284
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: spin_trylock include/linux/spinlock.h:361 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: qdisc_run_begin include/net/sch_generic.h:195 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_xmit_skb net/core/dev.c:3771 [inline]
  #8: ffff888014d9d258 (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+...}-{2:2}, at: __dev_queue_xmit+0x1262/0x3b10 net/core/dev.c:4325

stack backtrace:
CPU: 1 PID: 19016 Comm: syz-executor.0 Not tainted 6.8.0-rc4-next-20240212-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <IRQ>
  __dump_stack lib/dump_stack.c:88 [inline]
  dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114
  check_deadlock kernel/locking/lockdep.c:3062 [inline]
  validate_chain+0x15c1/0x58e0 kernel/locking/lockdep.c:3856
  __lock_acquire+0x1346/0x1fd0 kernel/locking/lockdep.c:5137
  lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
  __raw_spin_lock include/linux/spinlock_api_smp.h:133 [inline]
  _raw_spin_lock+0x2e/0x40 kernel/locking/spinlock.c:154
  spin_lock include/linux/spinlock.h:351 [inline]
  __netif_tx_lock include/linux/netdevice.h:4452 [inline]
  sch_direct_xmit+0x1c4/0x5f0 net/sched/sch_generic.c:340
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  iptunnel_xmit+0x540/0x9b0 net/ipv4/ip_tunnel_core.c:82
  ip_tunnel_xmit+0x20ee/0x2960 net/ipv4/ip_tunnel.c:831
  erspan_xmit+0x9de/0x1460 net/ipv4/ip_gre.c:720
  __netdev_start_xmit include/linux/netdevice.h:4989 [inline]
  netdev_start_xmit include/linux/netdevice.h:5003 [inline]
  xmit_one net/core/dev.c:3555 [inline]
  dev_hard_start_xmit+0x242/0x770 net/core/dev.c:3571
  sch_direct_xmit+0x2b6/0x5f0 net/sched/sch_generic.c:342
  __dev_xmit_skb net/core/dev.c:3784 [inline]
  __dev_queue_xmit+0x1912/0x3b10 net/core/dev.c:4325
  neigh_output include/net/neighbour.h:542 [inline]
  ip_finish_output2+0xe66/0x1360 net/ipv4/ip_output.c:235
  igmpv3_send_cr net/ipv4/igmp.c:723 [inline]
  igmp_ifc_timer_expire+0xb71/0xd90 net/ipv4/igmp.c:813
  call_timer_fn+0x17e/0x600 kernel/time/timer.c:1700
  expire_timers kernel/time/timer.c:1751 [inline]
  __run_timers+0x621/0x830 kernel/time/timer.c:2038
  run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2051
  __do_softirq+0x2bc/0x943 kernel/softirq.c:554
  invoke_softirq kernel/softirq.c:428 [inline]
  __irq_exit_rcu+0xf2/0x1c0 kernel/softirq.c:633
  irq_exit_rcu+0x9/0x30 kernel/softirq.c:645
  instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1076 [inline]
  sysvec_apic_timer_interrupt+0xa6/0xc0 arch/x86/kernel/apic/apic.c:1076
 </IRQ>
 <TASK>
  asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:702
 RIP: 0010:resched_offsets_ok kernel/sched/core.c:10127 [inline]
 RIP: 0010:__might_resched+0x16f/0x780 kernel/sched/core.c:10142
Code: 00 4c 89 e8 48 c1 e8 03 48 ba 00 00 00 00 00 fc ff df 48 89 44 24 38 0f b6 04 10 84 c0 0f 85 87 04 00 00 41 8b 45 00 c1 e0 08 <01> d8 44 39 e0 0f 85 d6 00 00 00 44 89 64 24 1c 48 8d bc 24 a0 00
RSP: 0018:ffffc9000ee069e0 EFLAGS: 00000246
RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8880296a9e00
RDX: dffffc0000000000 RSI: ffff8880296a9e00 RDI: ffffffff8bfe8fa0
RBP: ffffc9000ee06b00 R08: ffffffff82326877 R09: 1ffff11002b5ad1b
R10: dffffc0000000000 R11: ffffed1002b5ad1c R12: 0000000000000000
R13: ffff8880296aa23c R14: 000000000000062a R15: 1ffff92001dc0d44
  down_write+0x19/0x50 kernel/locking/rwsem.c:1578
  kernfs_activate fs/kernfs/dir.c:1403 [inline]
  kernfs_add_one+0x4af/0x8b0 fs/kernfs/dir.c:819
  __kernfs_create_file+0x22e/0x2e0 fs/kernfs/file.c:1056
  sysfs_add_file_mode_ns+0x24a/0x310 fs/sysfs/file.c:307
  create_files fs/sysfs/group.c:64 [inline]
  internal_create_group+0x4f4/0xf20 fs/sysfs/group.c:152
  internal_create_groups fs/sysfs/group.c:192 [inline]
  sysfs_create_groups+0x56/0x120 fs/sysfs/group.c:218
  create_dir lib/kobject.c:78 [inline]
  kobject_add_internal+0x472/0x8d0 lib/kobject.c:240
  kobject_add_varg lib/kobject.c:374 [inline]
  kobject_init_and_add+0x124/0x190 lib/kobject.c:457
  netdev_queue_add_kobject net/core/net-sysfs.c:1706 [inline]
  netdev_queue_update_kobjects+0x1f3/0x480 net/core/net-sysfs.c:1758
  register_queue_kobjects net/core/net-sysfs.c:1819 [inline]
  netdev_register_kobject+0x265/0x310 net/core/net-sysfs.c:2059
  register_netdevice+0x1191/0x19c0 net/core/dev.c:10298
  bond_newlink+0x3b/0x90 drivers/net/bonding/bond_netlink.c:576
  rtnl_newlink_create net/core/rtnetlink.c:3506 [inline]
  __rtnl_newlink net/core/rtnetlink.c:3726 [inline]
  rtnl_newlink+0x158f/0x20a0 net/core/rtnetlink.c:3739
  rtnetlink_rcv_msg+0x885/0x1040 net/core/rtnetlink.c:6606
  netlink_rcv_skb+0x1e3/0x430 net/netlink/af_netlink.c:2543
  netlink_unicast_kernel net/netlink/af_netlink.c:1341 [inline]
  netlink_unicast+0x7ea/0x980 net/netlink/af_netlink.c:1367
  netlink_sendmsg+0xa3c/0xd70 net/netlink/af_netlink.c:1908
  sock_sendmsg_nosec net/socket.c:730 [inline]
  __sock_sendmsg+0x221/0x270 net/socket.c:745
  __sys_sendto+0x3a4/0x4f0 net/socket.c:2191
  __do_sys_sendto net/socket.c:2203 [inline]
  __se_sys_sendto net/socket.c:2199 [inline]
  __x64_sys_sendto+0xde/0x100 net/socket.c:2199
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fc3fa87fa9c

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20240212140700.2795436-4-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
[ Upstream commit 1947b92464c3268381604bbe2ac977a3fd78192f ]

Parallel testing appears to show a race between allocating and setting
evsel ids. As there is a bounds check on the xyarray it yields a segv
like:

```
AddressSanitizer:DEADLYSIGNAL

=================================================================

==484408==ERROR: AddressSanitizer: SEGV on unknown address 0x000000000010

==484408==The signal is caused by a WRITE memory access.

==484408==Hint: address points to the zero page.

    #0 0x55cef5d4eff4 in perf_evlist__id_hash tools/lib/perf/evlist.c:256
    #1 0x55cef5d4f132 in perf_evlist__id_add tools/lib/perf/evlist.c:274
    #2 0x55cef5d4f545 in perf_evlist__id_add_fd tools/lib/perf/evlist.c:315
    #3 0x55cef5a1923f in store_evsel_ids util/evsel.c:3130
    #4 0x55cef5a19400 in evsel__store_ids util/evsel.c:3147
    #5 0x55cef5888204 in __run_perf_stat tools/perf/builtin-stat.c:832
    #6 0x55cef5888c06 in run_perf_stat tools/perf/builtin-stat.c:960
    #7 0x55cef58932db in cmd_stat tools/perf/builtin-stat.c:2878
...
```

Avoid this crash by early exiting the perf_evlist__id_add_fd and
perf_evlist__id_add is the access is out-of-bounds.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20240229070757.796244-1-irogers@google.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
[ Upstream commit f8bbc07ac535593139c875ffa19af924b1084540 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
commit 9e985cbf2942a1bb8fcef9adc2a17d90fd7ca8ee upstream.

Drop support for virtualizing adaptive PEBS, as KVM's implementation is
architecturally broken without an obvious/easy path forward, and because
exposing adaptive PEBS can leak host LBRs to the guest, i.e. can leak
host kernel addresses to the guest.

Bug #1 is that KVM doesn't account for the upper 32 bits of
IA32_FIXED_CTR_CTRL when (re)programming fixed counters, e.g
fixed_ctrl_field() drops the upper bits, reprogram_fixed_counters()
stores local variables as u8s and truncates the upper bits too, etc.

Bug #2 is that, because KVM _always_ sets precise_ip to a non-zero value
for PEBS events, perf will _always_ generate an adaptive record, even if
the guest requested a basic record.  Note, KVM will also enable adaptive
PEBS in individual *counter*, even if adaptive PEBS isn't exposed to the
guest, but this is benign as MSR_PEBS_DATA_CFG is guaranteed to be zero,
i.e. the guest will only ever see Basic records.

Bug #3 is in perf.  intel_pmu_disable_fixed() doesn't clear the upper
bits either, i.e. leaves ICL_FIXED_0_ADAPTIVE set, and
intel_pmu_enable_fixed() effectively doesn't clear ICL_FIXED_0_ADAPTIVE
either.  I.e. perf _always_ enables ADAPTIVE counters, regardless of what
KVM requests.

Bug #4 is that adaptive PEBS *might* effectively bypass event filters set
by the host, as "Updated Memory Access Info Group" records information
that might be disallowed by userspace via KVM_SET_PMU_EVENT_FILTER.

Bug #5 is that KVM doesn't ensure LBR MSRs hold guest values (or at least
zeros) when entering a vCPU with adaptive PEBS, which allows the guest
to read host LBRs, i.e. host RIPs/addresses, by enabling "LBR Entries"
records.

Disable adaptive PEBS support as an immediate fix due to the severity of
the LBR leak in particular, and because fixing all of the bugs will be
non-trivial, e.g. not suitable for backporting to stable kernels.

Note!  This will break live migration, but trying to make KVM play nice
with live migration would be quite complicated, wouldn't be guaranteed to
work (i.e. KVM might still kill/confuse the guest), and it's not clear
that there are any publicly available VMMs that support adaptive PEBS,
let alone live migrate VMs that support adaptive PEBS, e.g. QEMU doesn't
support PEBS in any capacity.

Link: https://lore.kernel.org/all/20240306230153.786365-1-seanjc@google.com
Link: https://lore.kernel.org/all/ZeepGjHCeSfadANM@google.com
Fixes: c59a1f1 ("KVM: x86/pmu: Add IA32_PEBS_ENABLE MSR emulation for extended PEBS")
Cc: stable@vger.kernel.org
Cc: Like Xu <like.xu.linux@gmail.com>
Cc: Mingwei Zhang <mizhang@google.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Zhang Xiong <xiong.y.zhang@intel.com>
Cc: Lv Zhiyuan <zhiyuan.lv@intel.com>
Cc: Dapeng Mi <dapeng1.mi@intel.com>
Cc: Jim Mattson <jmattson@google.com>
Acked-by: Like Xu <likexu@tencent.com>
Link: https://lore.kernel.org/r/20240307005833.827147-1-seanjc@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
commit 89f9a1e876b5a7ad884918c03a46831af202c8a0 upstream.

On the time to free xbc memory in xbc_exit(), memblock may has handed
over memory to buddy allocator. So it doesn't make sense to free memory
back to memblock. memblock_free() called by xbc_exit() even causes UAF bugs
on architectures with CONFIG_ARCH_KEEP_MEMBLOCK disabled like x86.
Following KASAN logs shows this case.

This patch fixes the xbc memory free problem by calling memblock_free()
in early xbc init error rewind path and calling memblock_free_late() in
xbc exit path to free memory to buddy allocator.

[    9.410890] ==================================================================
[    9.418962] BUG: KASAN: use-after-free in memblock_isolate_range+0x12d/0x260
[    9.426850] Read of size 8 at addr ffff88845dd30000 by task swapper/0/1

[    9.435901] CPU: 9 PID: 1 Comm: swapper/0 Tainted: G     U             6.9.0-rc3-00208-g586b5dfb51b9 #5
[    9.446403] Hardware name: Intel Corporation RPLP LP5 (CPU:RaptorLake)/RPLP LP5 (ID:13), BIOS IRPPN02.01.01.00.00.19.015.D-00000000 Dec 28 2023
[    9.460789] Call Trace:
[    9.463518]  <TASK>
[    9.465859]  dump_stack_lvl+0x53/0x70
[    9.469949]  print_report+0xce/0x610
[    9.473944]  ? __virt_addr_valid+0xf5/0x1b0
[    9.478619]  ? memblock_isolate_range+0x12d/0x260
[    9.483877]  kasan_report+0xc6/0x100
[    9.487870]  ? memblock_isolate_range+0x12d/0x260
[    9.493125]  memblock_isolate_range+0x12d/0x260
[    9.498187]  memblock_phys_free+0xb4/0x160
[    9.502762]  ? __pfx_memblock_phys_free+0x10/0x10
[    9.508021]  ? mutex_unlock+0x7e/0xd0
[    9.512111]  ? __pfx_mutex_unlock+0x10/0x10
[    9.516786]  ? kernel_init_freeable+0x2d4/0x430
[    9.521850]  ? __pfx_kernel_init+0x10/0x10
[    9.526426]  xbc_exit+0x17/0x70
[    9.529935]  kernel_init+0x38/0x1e0
[    9.533829]  ? _raw_spin_unlock_irq+0xd/0x30
[    9.538601]  ret_from_fork+0x2c/0x50
[    9.542596]  ? __pfx_kernel_init+0x10/0x10
[    9.547170]  ret_from_fork_asm+0x1a/0x30
[    9.551552]  </TASK>

[    9.555649] The buggy address belongs to the physical page:
[    9.561875] page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x1 pfn:0x45dd30
[    9.570821] flags: 0x200000000000000(node=0|zone=2)
[    9.576271] page_type: 0xffffffff()
[    9.580167] raw: 0200000000000000 ffffea0011774c48 ffffea0012ba1848 0000000000000000
[    9.588823] raw: 0000000000000001 0000000000000000 00000000ffffffff 0000000000000000
[    9.597476] page dumped because: kasan: bad access detected

[    9.605362] Memory state around the buggy address:
[    9.610714]  ffff88845dd2ff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.618786]  ffff88845dd2ff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
[    9.626857] >ffff88845dd30000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.634930]                    ^
[    9.638534]  ffff88845dd30080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.646605]  ffff88845dd30100: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff
[    9.654675] ==================================================================

Link: https://lore.kernel.org/all/20240414114944.1012359-1-qiang4.zhang@linux.intel.com/

Fixes: 40caa12 ("init: bootconfig: Remove all bootconfig data when the init memory is removed")
Cc: Stable@vger.kernel.org
Signed-off-by: Qiang Zhang <qiang4.zhang@intel.com>
Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue May 10, 2024
[ Upstream commit 54225988889931467a9b55fdbef534079b665519 ]

The rehash delayed work migrates filters from one region to another
according to the number of available credits.

The migrated from region is destroyed at the end of the work if the
number of credits is non-negative as the assumption is that this is
indicative of migration being complete. This assumption is incorrect as
a non-negative number of credits can also be the result of a failed
migration.

The destruction of a region that still has filters referencing it can
result in a use-after-free [1].

Fix by not destroying the region if migration failed.

[1]
BUG: KASAN: slab-use-after-free in mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
Read of size 8 at addr ffff8881735319e8 by task kworker/0:31/3858

CPU: 0 PID: 3858 Comm: kworker/0:31 Tainted: G        W          6.9.0-rc2-custom-00782-gf2275c2157d8 #5
Hardware name: Mellanox Technologies Ltd. MSN3700/VMOD0005, BIOS 5.11 01/06/2019
Workqueue: mlxsw_core mlxsw_sp_acl_tcam_vregion_rehash_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xc6/0x120
 print_report+0xce/0x670
 kasan_report+0xd7/0x110
 mlxsw_sp_acl_ctcam_region_entry_remove+0x21d/0x230
 mlxsw_sp_acl_ctcam_entry_del+0x2e/0x70
 mlxsw_sp_acl_atcam_entry_del+0x81/0x210
 mlxsw_sp_acl_tcam_vchunk_migrate_all+0x3cd/0xb50
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x157/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30
 </TASK>

Allocated by task 174:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 __kasan_kmalloc+0x8f/0xa0
 __kmalloc+0x19c/0x360
 mlxsw_sp_acl_tcam_region_create+0xdf/0x9c0
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x954/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Freed by task 7:
 kasan_save_stack+0x33/0x60
 kasan_save_track+0x14/0x30
 kasan_save_free_info+0x3b/0x60
 poison_slab_object+0x102/0x170
 __kasan_slab_free+0x14/0x30
 kfree+0xc1/0x290
 mlxsw_sp_acl_tcam_region_destroy+0x272/0x310
 mlxsw_sp_acl_tcam_vregion_rehash_work+0x731/0x1300
 process_one_work+0x8eb/0x19b0
 worker_thread+0x6c9/0xf70
 kthread+0x2c9/0x3b0
 ret_from_fork+0x4d/0x80
 ret_from_fork_asm+0x1a/0x30

Fixes: c9c9af9 ("mlxsw: spectrum_acl: Allow to interrupt/continue rehash work")
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Tested-by: Alexander Zubkov <green@qrator.net>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/3e412b5659ec2310c5c615760dfe5eac18dd7ebd.1713797103.git.petrm@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue May 17, 2024
[ Upstream commit f8bbc07ac535593139c875ffa19af924b1084540 ]

vhost_worker will call tun call backs to receive packets. If too many
illegal packets arrives, tun_do_read will keep dumping packet contents.
When console is enabled, it will costs much more cpu time to dump
packet and soft lockup will be detected.

net_ratelimit mechanism can be used to limit the dumping rate.

PID: 33036    TASK: ffff949da6f20000  CPU: 23   COMMAND: "vhost-32980"
 #0 [fffffe00003fce50] crash_nmi_callback at ffffffff89249253
 #1 [fffffe00003fce58] nmi_handle at ffffffff89225fa3
 #2 [fffffe00003fceb0] default_do_nmi at ffffffff8922642e
 #3 [fffffe00003fced0] do_nmi at ffffffff8922660d
 #4 [fffffe00003fcef0] end_repeat_nmi at ffffffff89c01663
    [exception RIP: io_serial_in+20]
    RIP: ffffffff89792594  RSP: ffffa655314979e8  RFLAGS: 00000002
    RAX: ffffffff89792500  RBX: ffffffff8af428a0  RCX: 0000000000000000
    RDX: 00000000000003fd  RSI: 0000000000000005  RDI: ffffffff8af428a0
    RBP: 0000000000002710   R8: 0000000000000004   R9: 000000000000000f
    R10: 0000000000000000  R11: ffffffff8acbf64f  R12: 0000000000000020
    R13: ffffffff8acbf698  R14: 0000000000000058  R15: 0000000000000000
    ORIG_RAX: ffffffffffffffff  CS: 0010  SS: 0018
 #5 [ffffa655314979e8] io_serial_in at ffffffff89792594
 #6 [ffffa655314979e8] wait_for_xmitr at ffffffff89793470
 #7 [ffffa65531497a08] serial8250_console_putchar at ffffffff897934f6
 #8 [ffffa65531497a20] uart_console_write at ffffffff8978b605
 #9 [ffffa65531497a48] serial8250_console_write at ffffffff89796558
 #10 [ffffa65531497ac8] console_unlock at ffffffff89316124
 #11 [ffffa65531497b10] vprintk_emit at ffffffff89317c07
 #12 [ffffa65531497b68] printk at ffffffff89318306
 #13 [ffffa65531497bc8] print_hex_dump at ffffffff89650765
 #14 [ffffa65531497ca8] tun_do_read at ffffffffc0b06c27 [tun]
 #15 [ffffa65531497d38] tun_recvmsg at ffffffffc0b06e34 [tun]
 #16 [ffffa65531497d68] handle_rx at ffffffffc0c5d682 [vhost_net]
 #17 [ffffa65531497ed0] vhost_worker at ffffffffc0c644dc [vhost]
 #18 [ffffa65531497f10] kthread at ffffffff892d2e72
 #19 [ffffa65531497f50] ret_from_fork at ffffffff89c0022f

Fixes: ef3db4a ("tun: avoid BUG, dump packet on GSO errors")
Signed-off-by: Lei Chen <lei.chen@smartx.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Acked-by: Jason Wang <jasowang@redhat.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Link: https://lore.kernel.org/r/20240415020247.2207781-1-lei.chen@smartx.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jun 3, 2024
[ Upstream commit fc3a5534e2a8855427403113cbeb54af5837bbe0 ]

An issue occurred while reading an ELF file in libbpf.c during fuzzing:

	Program received signal SIGSEGV, Segmentation fault.
	0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	4206 in libbpf.c
	(gdb) bt
	#0 0x0000000000958e97 in bpf_object.collect_prog_relos () at libbpf.c:4206
	#1 0x000000000094f9d6 in bpf_object.collect_relos () at libbpf.c:6706
	#2 0x000000000092bef3 in bpf_object_open () at libbpf.c:7437
	#3 0x000000000092c046 in bpf_object.open_mem () at libbpf.c:7497
	#4 0x0000000000924afa in LLVMFuzzerTestOneInput () at fuzz/bpf-object-fuzzer.c:16
	#5 0x000000000060be11 in testblitz_engine::fuzzer::Fuzzer::run_one ()
	#6 0x000000000087ad92 in tracing::span::Span::in_scope ()
	#7 0x00000000006078aa in testblitz_engine::fuzzer::util::walkdir ()
	#8 0x00000000005f3217 in testblitz_engine::entrypoint::main::{{closure}} ()
	#9 0x00000000005f2601 in main ()
	(gdb)

scn_data was null at this code(tools/lib/bpf/src/libbpf.c):

	if (rel->r_offset % BPF_INSN_SZ || rel->r_offset >= scn_data->d_size) {

The scn_data is derived from the code above:

	scn = elf_sec_by_idx(obj, sec_idx);
	scn_data = elf_sec_data(obj, scn);

	relo_sec_name = elf_sec_str(obj, shdr->sh_name);
	sec_name = elf_sec_name(obj, scn);
	if (!relo_sec_name || !sec_name)// don't check whether scn_data is NULL
		return -EINVAL;

In certain special scenarios, such as reading a malformed ELF file,
it is possible that scn_data may be a null pointer

Signed-off-by: Mingyi Zhang <zhangmingyi5@huawei.com>
Signed-off-by: Xin Liu <liuxin350@huawei.com>
Signed-off-by: Changye Wu <wuchangye@huawei.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20231221033947.154564-1-liuxin350@huawei.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jun 3, 2024
commit 817349b6d26aadd8b38283a05ce0bab106b4c765 upstream.

Upstream commit bac1ec5 ("usb: xhci: Set quirk for
XHCI_SG_TRB_CACHE_SIZE_QUIRK") introduced a new quirk in XHCI
which fixes XHC timeout, which was seen on synopsys XHCs while
using SG buffers. But the support for this quirk isn't present
in the DWC3 layer.

We will encounter this XHCI timeout/hung issue if we run iperf
loopback tests using RTL8156 ethernet adaptor on DWC3 targets
with scatter-gather enabled. This gets resolved after enabling
the XHCI_SG_TRB_CACHE_SIZE_QUIRK. This patch enables it using
the xhci device property since its needed for DWC3 controller.

In Synopsys DWC3 databook,
Table 9-3: xHCI Debug Capability Limitations
Chained TRBs greater than TRB cache size: The debug capability
driver must not create a multi-TRB TD that describes smaller
than a 1K packet that spreads across 8 or more TRBs on either
the IN TR or the OUT TR.

Cc: stable@vger.kernel.org #5.11
Signed-off-by: Prashanth K <quic_prashk@quicinc.com>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20240116055816.1169821-2-quic_prashk@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jun 26, 2024
commit c2274b908db05529980ec056359fae916939fdaa upstream.

The reader code in rb_get_reader_page() swaps a new reader page into the
ring buffer by doing cmpxchg on old->list.prev->next to point it to the
new page. Following that, if the operation is successful,
old->list.next->prev gets updated too. This means the underlying
doubly-linked list is temporarily inconsistent, page->prev->next or
page->next->prev might not be equal back to page for some page in the
ring buffer.

The resize operation in ring_buffer_resize() can be invoked in parallel.
It calls rb_check_pages() which can detect the described inconsistency
and stop further tracing:

[  190.271762] ------------[ cut here ]------------
[  190.271771] WARNING: CPU: 1 PID: 6186 at kernel/trace/ring_buffer.c:1467 rb_check_pages.isra.0+0x6a/0xa0
[  190.271789] Modules linked in: [...]
[  190.271991] Unloaded tainted modules: intel_uncore_frequency(E):1 skx_edac(E):1
[  190.272002] CPU: 1 PID: 6186 Comm: cmd.sh Kdump: loaded Tainted: G            E      6.9.0-rc6-default #5 158d3e1e6d0b091c34c3b96bfd99a1c58306d79f
[  190.272011] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.16.0-0-gd239552c-rebuilt.opensuse.org 04/01/2014
[  190.272015] RIP: 0010:rb_check_pages.isra.0+0x6a/0xa0
[  190.272023] Code: [...]
[  190.272028] RSP: 0018:ffff9c37463abb70 EFLAGS: 00010206
[  190.272034] RAX: ffff8eba04b6cb80 RBX: 0000000000000007 RCX: ffff8eba01f13d80
[  190.272038] RDX: ffff8eba01f130c0 RSI: ffff8eba04b6cd00 RDI: ffff8eba0004c700
[  190.272042] RBP: ffff8eba0004c700 R08: 0000000000010002 R09: 0000000000000000
[  190.272045] R10: 00000000ffff7f52 R11: ffff8eba7f600000 R12: ffff8eba0004c720
[  190.272049] R13: ffff8eba00223a00 R14: 0000000000000008 R15: ffff8eba067a8000
[  190.272053] FS:  00007f1bd64752c0(0000) GS:ffff8eba7f680000(0000) knlGS:0000000000000000
[  190.272057] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  190.272061] CR2: 00007f1bd6662590 CR3: 000000010291e001 CR4: 0000000000370ef0
[  190.272070] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  190.272073] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  190.272077] Call Trace:
[  190.272098]  <TASK>
[  190.272189]  ring_buffer_resize+0x2ab/0x460
[  190.272199]  __tracing_resize_ring_buffer.part.0+0x23/0xa0
[  190.272206]  tracing_resize_ring_buffer+0x65/0x90
[  190.272216]  tracing_entries_write+0x74/0xc0
[  190.272225]  vfs_write+0xf5/0x420
[  190.272248]  ksys_write+0x67/0xe0
[  190.272256]  do_syscall_64+0x82/0x170
[  190.272363]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  190.272373] RIP: 0033:0x7f1bd657d263
[  190.272381] Code: [...]
[  190.272385] RSP: 002b:00007ffe72b643f8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001
[  190.272391] RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f1bd657d263
[  190.272395] RDX: 0000000000000002 RSI: 0000555a6eb538e0 RDI: 0000000000000001
[  190.272398] RBP: 0000555a6eb538e0 R08: 000000000000000a R09: 0000000000000000
[  190.272401] R10: 0000555a6eb55190 R11: 0000000000000246 R12: 00007f1bd6662500
[  190.272404] R13: 0000000000000002 R14: 00007f1bd6667c00 R15: 0000000000000002
[  190.272412]  </TASK>
[  190.272414] ---[ end trace 0000000000000000 ]---

Note that ring_buffer_resize() calls rb_check_pages() only if the parent
trace_buffer has recording disabled. Recent commit d78ab792705c
("tracing: Stop current tracer when resizing buffer") causes that it is
now always the case which makes it more likely to experience this issue.

The window to hit this race is nonetheless very small. To help
reproducing it, one can add a delay loop in rb_get_reader_page():

 ret = rb_head_page_replace(reader, cpu_buffer->reader_page);
 if (!ret)
 	goto spin;
 for (unsigned i = 0; i < 1U << 26; i++)  /* inserted delay loop */
 	__asm__ __volatile__ ("" : : : "memory");
 rb_list_head(reader->list.next)->prev = &cpu_buffer->reader_page->list;

.. and then run the following commands on the target system:

 echo 1 > /sys/kernel/tracing/events/sched/sched_switch/enable
 while true; do
 	echo 16 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 	echo 8 > /sys/kernel/tracing/buffer_size_kb; sleep 0.1
 done &
 while true; do
 	for i in /sys/kernel/tracing/per_cpu/*; do
 		timeout 0.1 cat $i/trace_pipe; sleep 0.2
 	done
 done

To fix the problem, make sure ring_buffer_resize() doesn't invoke
rb_check_pages() concurrently with a reader operating on the same
ring_buffer_per_cpu by taking its cpu_buffer->reader_lock.

Link: https://lore.kernel.org/linux-trace-kernel/20240517134008.24529-3-petr.pavlu@suse.com

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Fixes: 659f451 ("ring-buffer: Add integrity check at end of iter read")
Signed-off-by: Petr Pavlu <petr.pavlu@suse.com>
[ Fixed whitespace ]
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sys-oak pushed a commit that referenced this issue Jun 26, 2024
[ Upstream commit 88ce0106a1f603bf360cb397e8fe293f8298fabb ]

The session has a header in it which contains a perf env with
bpf_progs. The bpf_progs are accessed by the sideband thread and so
the sideband thread must be stopped before the session is deleted, to
avoid a use after free.  This error was detected by AddressSanitizer
in the following:

  ==2054673==ERROR: AddressSanitizer: heap-use-after-free on address 0x61d000161e00 at pc 0x55769289de54 bp 0x7f9df36d4ab0 sp 0x7f9df36d4aa8
  READ of size 8 at 0x61d000161e00 thread T1
      #0 0x55769289de53 in __perf_env__insert_bpf_prog_info util/env.c:42
      #1 0x55769289dbb1 in perf_env__insert_bpf_prog_info util/env.c:29
      #2 0x557692bbae29 in perf_env__add_bpf_info util/bpf-event.c:483
      #3 0x557692bbb01a in bpf_event__sb_cb util/bpf-event.c:512
      #4 0x5576928b75f4 in perf_evlist__poll_thread util/sideband_evlist.c:68
      #5 0x7f9df96a63eb in start_thread nptl/pthread_create.c:444
      #6 0x7f9df9726a4b in clone3 ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81

  0x61d000161e00 is located 384 bytes inside of 2136-byte region [0x61d000161c80,0x61d0001624d8)
  freed by thread T0 here:
      #0 0x7f9dfa6d7288 in __interceptor_free libsanitizer/asan/asan_malloc_linux.cpp:52
      #1 0x557692978d50 in perf_session__delete util/session.c:319
      #2 0x557692673959 in __cmd_record tools/perf/builtin-record.c:2884
      #3 0x55769267a9f0 in cmd_record tools/perf/builtin-record.c:4259
      #4 0x55769286710c in run_builtin tools/perf/perf.c:349
      #5 0x557692867678 in handle_internal_command tools/perf/perf.c:402
      #6 0x557692867a40 in run_argv tools/perf/perf.c:446
      #7 0x557692867fae in main tools/perf/perf.c:562
      #8 0x7f9df96456c9 in __libc_start_call_main ../sysdeps/nptl/libc_start_call_main.h:58

Fixes: 657ee55 ("perf evlist: Introduce side band thread")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Disha Goel <disgoel@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240301074639.2260708-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jun 26, 2024
[ Upstream commit 769e6a1e15bdbbaf2b0d2f37c24f2c53268bd21f ]

ui_browser__show() is capturing the input title that is stack allocated
memory in hist_browser__run().

Avoid a use after return by strdup-ing the string.

Committer notes:

Further explanation from Ian Rogers:

My command line using tui is:
$ sudo bash -c 'rm /tmp/asan.log*; export
ASAN_OPTIONS="log_path=/tmp/asan.log"; /tmp/perf/perf mem record -a
sleep 1; /tmp/perf/perf mem report'
I then go to the perf annotate view and quit. This triggers the asan
error (from the log file):
```
==1254591==ERROR: AddressSanitizer: stack-use-after-return on address
0x7f2813331920 at pc 0x7f28180
65991 bp 0x7fff0a21c750 sp 0x7fff0a21bf10
READ of size 80 at 0x7f2813331920 thread T0
    #0 0x7f2818065990 in __interceptor_strlen
../../../../src/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:461
    #1 0x7f2817698251 in SLsmg_write_wrapped_string
(/lib/x86_64-linux-gnu/libslang.so.2+0x98251)
    #2 0x7f28176984b9 in SLsmg_write_nstring
(/lib/x86_64-linux-gnu/libslang.so.2+0x984b9)
    #3 0x55c94045b365 in ui_browser__write_nstring ui/browser.c:60
    #4 0x55c94045c558 in __ui_browser__show_title ui/browser.c:266
    #5 0x55c94045c776 in ui_browser__show ui/browser.c:288
    #6 0x55c94045c06d in ui_browser__handle_resize ui/browser.c:206
    #7 0x55c94047979b in do_annotate ui/browsers/hists.c:2458
    #8 0x55c94047fb17 in evsel__hists_browse ui/browsers/hists.c:3412
    #9 0x55c940480a0c in perf_evsel_menu__run ui/browsers/hists.c:3527
    #10 0x55c940481108 in __evlist__tui_browse_hists ui/browsers/hists.c:3613
    #11 0x55c9404813f7 in evlist__tui_browse_hists ui/browsers/hists.c:3661
    #12 0x55c93ffa253f in report__browse_hists tools/perf/builtin-report.c:671
    #13 0x55c93ffa58ca in __cmd_report tools/perf/builtin-report.c:1141
    #14 0x55c93ffaf159 in cmd_report tools/perf/builtin-report.c:1805
    #15 0x55c94000c05c in report_events tools/perf/builtin-mem.c:374
    #16 0x55c94000d96d in cmd_mem tools/perf/builtin-mem.c:516
    #17 0x55c9400e44ee in run_builtin tools/perf/perf.c:350
    #18 0x55c9400e4a5a in handle_internal_command tools/perf/perf.c:403
    #19 0x55c9400e4e22 in run_argv tools/perf/perf.c:447
    #20 0x55c9400e53ad in main tools/perf/perf.c:561
    #21 0x7f28170456c9 in __libc_start_call_main
../sysdeps/nptl/libc_start_call_main.h:58
    #22 0x7f2817045784 in __libc_start_main_impl ../csu/libc-start.c:360
    #23 0x55c93ff544c0 in _start (/tmp/perf/perf+0x19a4c0) (BuildId:
84899b0e8c7d3a3eaa67b2eb35e3d8b2f8cd4c93)

Address 0x7f2813331920 is located in stack of thread T0 at offset 32 in frame
    #0 0x55c94046e85e in hist_browser__run ui/browsers/hists.c:746

  This frame has 1 object(s):
    [32, 192) 'title' (line 747) <== Memory access at offset 32 is
inside this variable
HINT: this may be a false positive if your program uses some custom
stack unwind mechanism, swapcontext or vfork
```
hist_browser__run isn't on the stack so the asan error looks legit.
There's no clean init/exit on struct ui_browser so I may be trading a
use-after-return for a memory leak, but that seems look a good trade
anyway.

Fixes: 05e8b08 ("perf ui browser: Stop using 'self'")
Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ben Gainey <ben.gainey@arm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Li Dong <lidong@vivo.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Oliver Upton <oliver.upton@linux.dev>
Cc: Paran Lee <p4ranlee@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sun Haiyong <sunhaiyong@loongson.cn>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Yanteng Si <siyanteng@loongson.cn>
Cc: Yicong Yang <yangyicong@hisilicon.com>
Link: https://lore.kernel.org/r/20240507183545.1236093-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
sys-oak pushed a commit that referenced this issue Jun 26, 2024
commit 9d274c19a71b3a276949933859610721a453946b upstream.

We have been seeing crashes on duplicate keys in
btrfs_set_item_key_safe():

  BTRFS critical (device vdb): slot 4 key (450 108 8192) new key (450 108 8192)
  ------------[ cut here ]------------
  kernel BUG at fs/btrfs/ctree.c:2620!
  invalid opcode: 0000 [#1] PREEMPT SMP PTI
  CPU: 0 PID: 3139 Comm: xfs_io Kdump: loaded Not tainted 6.9.0 #6
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.3-2.fc40 04/01/2014
  RIP: 0010:btrfs_set_item_key_safe+0x11f/0x290 [btrfs]

With the following stack trace:

  #0  btrfs_set_item_key_safe (fs/btrfs/ctree.c:2620:4)
  #1  btrfs_drop_extents (fs/btrfs/file.c:411:4)
  #2  log_one_extent (fs/btrfs/tree-log.c:4732:9)
  #3  btrfs_log_changed_extents (fs/btrfs/tree-log.c:4955:9)
  #4  btrfs_log_inode (fs/btrfs/tree-log.c:6626:9)
  #5  btrfs_log_inode_parent (fs/btrfs/tree-log.c:7070:8)
  #6  btrfs_log_dentry_safe (fs/btrfs/tree-log.c:7171:8)
  #7  btrfs_sync_file (fs/btrfs/file.c:1933:8)
  #8  vfs_fsync_range (fs/sync.c:188:9)
  #9  vfs_fsync (fs/sync.c:202:9)
  #10 do_fsync (fs/sync.c:212:9)
  #11 __do_sys_fdatasync (fs/sync.c:225:9)
  #12 __se_sys_fdatasync (fs/sync.c:223:1)
  #13 __x64_sys_fdatasync (fs/sync.c:223:1)
  #14 do_syscall_x64 (arch/x86/entry/common.c:52:14)
  #15 do_syscall_64 (arch/x86/entry/common.c:83:7)
  #16 entry_SYSCALL_64+0xaf/0x14c (arch/x86/entry/entry_64.S:121)

So we're logging a changed extent from fsync, which is splitting an
extent in the log tree. But this split part already exists in the tree,
triggering the BUG().

This is the state of the log tree at the time of the crash, dumped with
drgn (https://github.com/osandov/drgn/blob/main/contrib/btrfs_tree.py)
to get more details than btrfs_print_leaf() gives us:

  >>> print_extent_buffer(prog.crashed_thread().stack_trace()[0]["eb"])
  leaf 33439744 level 0 items 72 generation 9 owner 18446744073709551610
  leaf 33439744 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
          item 0 key (450 INODE_ITEM 0) itemoff 16123 itemsize 160
                  generation 7 transid 9 size 8192 nbytes 8473563889606862198
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 204 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417704.983333333 (2024-05-22 15:41:44)
                  mtime 1716417704.983333333 (2024-05-22 15:41:44)
                  otime 17592186044416.000000000 (559444-03-08 01:40:16)
          item 1 key (450 INODE_REF 256) itemoff 16110 itemsize 13
                  index 195 namelen 3 name: 193
          item 2 key (450 XATTR_ITEM 1640047104) itemoff 16073 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 3 key (450 EXTENT_DATA 0) itemoff 16020 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 4096 ram 12288
                  extent compression 0 (none)
          item 4 key (450 EXTENT_DATA 4096) itemoff 15967 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 4096 nr 8192
          item 5 key (450 EXTENT_DATA 8192) itemoff 15914 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096
  ...

So the real problem happened earlier: notice that items 4 (4k-12k) and 5
(8k-12k) overlap. Both are prealloc extents. Item 4 straddles i_size and
item 5 starts at i_size.

Here is the state of the filesystem tree at the time of the crash:

  >>> root = prog.crashed_thread().stack_trace()[2]["inode"].root
  >>> ret, nodes, slots = btrfs_search_slot(root, BtrfsKey(450, 0, 0))
  >>> print_extent_buffer(nodes[0])
  leaf 30425088 level 0 items 184 generation 9 owner 5
  leaf 30425088 flags 0x100000000000000
  fs uuid e5bd3946-400c-4223-8923-190ef1f18677
  chunk uuid d58cb17e-6d02-494a-829a-18b7d8a399da
  	...
          item 179 key (450 INODE_ITEM 0) itemoff 4907 itemsize 160
                  generation 7 transid 7 size 4096 nbytes 12288
                  block group 0 mode 100600 links 1 uid 0 gid 0 rdev 0
                  sequence 6 flags 0x10(PREALLOC)
                  atime 1716417703.220000000 (2024-05-22 15:41:43)
                  ctime 1716417703.220000000 (2024-05-22 15:41:43)
                  mtime 1716417703.220000000 (2024-05-22 15:41:43)
                  otime 1716417703.220000000 (2024-05-22 15:41:43)
          item 180 key (450 INODE_REF 256) itemoff 4894 itemsize 13
                  index 195 namelen 3 name: 193
          item 181 key (450 XATTR_ITEM 1640047104) itemoff 4857 itemsize 37
                  location key (0 UNKNOWN.0 0) type XATTR
                  transid 7 data_len 1 name_len 6
                  name: user.a
                  data a
          item 182 key (450 EXTENT_DATA 0) itemoff 4804 itemsize 53
                  generation 9 type 1 (regular)
                  extent data disk byte 303144960 nr 12288
                  extent data offset 0 nr 8192 ram 12288
                  extent compression 0 (none)
          item 183 key (450 EXTENT_DATA 8192) itemoff 4751 itemsize 53
                  generation 9 type 2 (prealloc)
                  prealloc data disk byte 303144960 nr 12288
                  prealloc data offset 8192 nr 4096

Item 5 in the log tree corresponds to item 183 in the filesystem tree,
but nothing matches item 4. Furthermore, item 183 is the last item in
the leaf.

btrfs_log_prealloc_extents() is responsible for logging prealloc extents
beyond i_size. It first truncates any previously logged prealloc extents
that start beyond i_size. Then, it walks the filesystem tree and copies
the prealloc extent items to the log tree.

If it hits the end of a leaf, then it calls btrfs_next_leaf(), which
unlocks the tree and does another search. However, while the filesystem
tree is unlocked, an ordered extent completion may modify the tree. In
particular, it may insert an extent item that overlaps with an extent
item that was already copied to the log tree.

This may manifest in several ways depending on the exact scenario,
including an EEXIST error that is silently translated to a full sync,
overlapping items in the log tree, or this crash. This particular crash
is triggered by the following sequence of events:

- Initially, the file has i_size=4k, a regular extent from 0-4k, and a
  prealloc extent beyond i_size from 4k-12k. The prealloc extent item is
  the last item in its B-tree leaf.
- The file is fsync'd, which copies its inode item and both extent items
  to the log tree.
- An xattr is set on the file, which sets the
  BTRFS_INODE_COPY_EVERYTHING flag.
- The range 4k-8k in the file is written using direct I/O. i_size is
  extended to 8k, but the ordered extent is still in flight.
- The file is fsync'd. Since BTRFS_INODE_COPY_EVERYTHING is set, this
  calls copy_inode_items_to_log(), which calls
  btrfs_log_prealloc_extents().
- btrfs_log_prealloc_extents() finds the 4k-12k prealloc extent in the
  filesystem tree. Since it starts before i_size, it skips it. Since it
  is the last item in its B-tree leaf, it calls btrfs_next_leaf().
- btrfs_next_leaf() unlocks the path.
- The ordered extent completion runs, which converts the 4k-8k part of
  the prealloc extent to written and inserts the remaining prealloc part
  from 8k-12k.
- btrfs_next_leaf() does a search and finds the new prealloc extent
  8k-12k.
- btrfs_log_prealloc_extents() copies the 8k-12k prealloc extent into
  the log tree. Note that it overlaps with the 4k-12k prealloc extent
  that was copied to the log tree by the first fsync.
- fsync calls btrfs_log_changed_extents(), which tries to log the 4k-8k
  extent that was written.
- This tries to drop the range 4k-8k in the log tree, which requires
  adjusting the start of the 4k-12k prealloc extent in the log tree to
  8k.
- btrfs_set_item_key_safe() sees that there is already an extent
  starting at 8k in the log tree and calls BUG().

Fix this by detecting when we're about to insert an overlapping file
extent item in the log tree and truncating the part that would overlap.

CC: stable@vger.kernel.org # 6.1+
Reviewed-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: Omar Sandoval <osandov@fb.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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