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ARM: dts: stm32: use pll4_p for ethernet PTP clock #3

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ddrown
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@ddrown ddrown commented Apr 23, 2020

IEEE 1588 support needs a clock defined as ptp_ref and this uses pll4_p as the parent clock

before:
$ ./testptp -g ; sleep 1 ; ./testptp -g
clock time: 0.000000000 or Wed Dec 31 18:00:00 1969
clock time: 0.000000000 or Wed Dec 31 18:00:00 1969

after:
$ ./testptp -g ; sleep 1 ; ./testptp -g
clock time: 1587623094.279486315 or Thu Apr 23 01:24:54 2020
clock time: 1587623095.292978915 or Thu Apr 23 01:24:55 2020

IEEE 1588 support needs a clock defined as ptp_ref and this uses pll4_p
as the parent clock
@ST-dot-com
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@ST-dot-com ST-dot-com closed this Apr 23, 2020
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
[ Upstream commit 102210f ]

rmnet_get_port() internally calls rcu_dereference_rtnl(),
which checks RTNL.
But rmnet_get_port() could be called by packet path.
The packet path is not protected by RTNL.
So, the suspicious RCU usage problem occurs.

Test commands:
    modprobe rmnet
    ip netns add nst
    ip link add veth0 type veth peer name veth1
    ip link set veth1 netns nst
    ip link add rmnet0 link veth0 type rmnet mux_id 1
    ip netns exec nst ip link add rmnet1 link veth1 type rmnet mux_id 1
    ip netns exec nst ip link set veth1 up
    ip netns exec nst ip link set rmnet1 up
    ip netns exec nst ip a a 192.168.100.2/24 dev rmnet1
    ip link set veth0 up
    ip link set rmnet0 up
    ip a a 192.168.100.1/24 dev rmnet0
    ping 192.168.100.2

Splat looks like:
[  146.630958][ T1174] WARNING: suspicious RCU usage
[  146.631735][ T1174] 5.6.0-rc1+ torvalds#447 Not tainted
[  146.632387][ T1174] -----------------------------
[  146.633151][ T1174] drivers/net/ethernet/qualcomm/rmnet/rmnet_config.c:386 suspicious rcu_dereference_check() !
[  146.634742][ T1174]
[  146.634742][ T1174] other info that might help us debug this:
[  146.634742][ T1174]
[  146.645992][ T1174]
[  146.645992][ T1174] rcu_scheduler_active = 2, debug_locks = 1
[  146.646937][ T1174] 5 locks held by ping/1174:
[  146.647609][ T1174]  #0: ffff8880c31dea70 (sk_lock-AF_INET){+.+.}, at: raw_sendmsg+0xab8/0x2980
[  146.662463][ T1174]  #1: ffffffff93925660 (rcu_read_lock_bh){....}, at: ip_finish_output2+0x243/0x2150
[  146.671696][ T1174]  #2: ffffffff93925660 (rcu_read_lock_bh){....}, at: __dev_queue_xmit+0x213/0x2940
[  146.673064][ T1174]  #3: ffff8880c19ecd58 (&dev->qdisc_running_key#7){+...}, at: ip_finish_output2+0x714/0x2150
[  146.690358][ T1174]  #4: ffff8880c5796898 (&dev->qdisc_xmit_lock_key#3){+.-.}, at: sch_direct_xmit+0x1e2/0x1020
[  146.699875][ T1174]
[  146.699875][ T1174] stack backtrace:
[  146.701091][ T1174] CPU: 0 PID: 1174 Comm: ping Not tainted 5.6.0-rc1+ torvalds#447
[  146.705215][ T1174] Hardware name: innotek GmbH VirtualBox/VirtualBox, BIOS VirtualBox 12/01/2006
[  146.706565][ T1174] Call Trace:
[  146.707102][ T1174]  dump_stack+0x96/0xdb
[  146.708007][ T1174]  rmnet_get_port.part.9+0x76/0x80 [rmnet]
[  146.709233][ T1174]  rmnet_egress_handler+0x107/0x420 [rmnet]
[  146.710492][ T1174]  ? sch_direct_xmit+0x1e2/0x1020
[  146.716193][ T1174]  rmnet_vnd_start_xmit+0x3d/0xa0 [rmnet]
[  146.717012][ T1174]  dev_hard_start_xmit+0x160/0x740
[  146.717854][ T1174]  sch_direct_xmit+0x265/0x1020
[  146.718577][ T1174]  ? register_lock_class+0x14d0/0x14d0
[  146.719429][ T1174]  ? dev_watchdog+0xac0/0xac0
[  146.723738][ T1174]  ? __dev_queue_xmit+0x15fd/0x2940
[  146.724469][ T1174]  ? lock_acquire+0x164/0x3b0
[  146.725172][ T1174]  __dev_queue_xmit+0x20c7/0x2940
[ ... ]

Fixes: ceed73a ("drivers: net: ethernet: qualcomm: rmnet: Initial implementation")
Signed-off-by: Taehee Yoo <ap420073@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
[ Upstream commit 6c5d911 ]

journal_head::b_transaction and journal_head::b_next_transaction could
be accessed concurrently as noticed by KCSAN,

 LTP: starting fsync04
 /dev/zero: Can't open blockdev
 EXT4-fs (loop0): mounting ext3 file system using the ext4 subsystem
 EXT4-fs (loop0): mounted filesystem with ordered data mode. Opts: (null)
 ==================================================================
 BUG: KCSAN: data-race in __jbd2_journal_refile_buffer [jbd2] / jbd2_write_access_granted [jbd2]

 write to 0xffff99f9b1bd0e30 of 8 bytes by task 25721 on cpu 70:
  __jbd2_journal_refile_buffer+0xdd/0x210 [jbd2]
  __jbd2_journal_refile_buffer at fs/jbd2/transaction.c:2569
  jbd2_journal_commit_transaction+0x2d15/0x3f20 [jbd2]
  (inlined by) jbd2_journal_commit_transaction at fs/jbd2/commit.c:1034
  kjournald2+0x13b/0x450 [jbd2]
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 read to 0xffff99f9b1bd0e30 of 8 bytes by task 25724 on cpu 68:
  jbd2_write_access_granted+0x1b2/0x250 [jbd2]
  jbd2_write_access_granted at fs/jbd2/transaction.c:1155
  jbd2_journal_get_write_access+0x2c/0x60 [jbd2]
  __ext4_journal_get_write_access+0x50/0x90 [ext4]
  ext4_mb_mark_diskspace_used+0x158/0x620 [ext4]
  ext4_mb_new_blocks+0x54f/0xca0 [ext4]
  ext4_ind_map_blocks+0xc79/0x1b40 [ext4]
  ext4_map_blocks+0x3b4/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block+0x3b/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 5 locks held by fsync04/25724:
  #0: ffff99f9911093f8 (sb_writers#13){.+.+}, at: vfs_write+0x21c/0x260
  #1: ffff99f9db4c0348 (&sb->s_type->i_mutex_key#15){+.+.}, at: ext4_buffered_write_iter+0x65/0x210 [ext4]
  #2: ffff99f5e7dfcf58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  #3: ffff99f9db4c0168 (&ei->i_data_sem){++++}, at: ext4_map_blocks+0x176/0x950 [ext4]
  #4: ffffffff99086b40 (rcu_read_lock){....}, at: jbd2_write_access_granted+0x4e/0x250 [jbd2]
 irq event stamp: 1407125
 hardirqs last  enabled at (1407125): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (1407124): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (1405528): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (1405521): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 68 PID: 25724 Comm: fsync04 Tainted: G L 5.6.0-rc2-next-20200221+ #7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019

The plain reads are outside of jh->b_state_lock critical section which result
in data races. Fix them by adding pairs of READ|WRITE_ONCE().

Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Qian Cai <cai@lca.pw>
Link: https://lore.kernel.org/r/20200222043111.2227-1-cai@lca.pw
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
…event

commit 7d36665 upstream.

An eventfd monitors multiple memory thresholds of the cgroup, closes them,
the kernel deletes all events related to this eventfd.  Before all events
are deleted, another eventfd monitors the memory threshold of this cgroup,
leading to a crash:

  BUG: kernel NULL pointer dereference, address: 0000000000000004
  #PF: supervisor write access in kernel mode
  #PF: error_code(0x0002) - not-present page
  PGD 800000033058e067 P4D 800000033058e067 PUD 3355ce067 PMD 0
  Oops: 0002 [#1] SMP PTI
  CPU: 2 PID: 14012 Comm: kworker/2:6 Kdump: loaded Not tainted 5.6.0-rc4 #3
  Hardware name: LENOVO 20AWS01K00/20AWS01K00, BIOS GLET70WW (2.24 ) 05/21/2014
  Workqueue: events memcg_event_remove
  RIP: 0010:__mem_cgroup_usage_unregister_event+0xb3/0x190
  RSP: 0018:ffffb47e01c4fe18 EFLAGS: 00010202
  RAX: 0000000000000001 RBX: ffff8bb223a8a000 RCX: 0000000000000001
  RDX: 0000000000000001 RSI: ffff8bb22fb83540 RDI: 0000000000000001
  RBP: ffffb47e01c4fe48 R08: 0000000000000000 R09: 0000000000000010
  R10: 000000000000000c R11: 071c71c71c71c71c R12: ffff8bb226aba880
  R13: ffff8bb223a8a480 R14: 0000000000000000 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff8bb242680000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000004 CR3: 000000032c29c003 CR4: 00000000001606e0
  Call Trace:
    memcg_event_remove+0x32/0x90
    process_one_work+0x172/0x380
    worker_thread+0x49/0x3f0
    kthread+0xf8/0x130
    ret_from_fork+0x35/0x40
  CR2: 0000000000000004

We can reproduce this problem in the following ways:

1. We create a new cgroup subdirectory and a new eventfd, and then we
   monitor multiple memory thresholds of the cgroup through this eventfd.

2.  closing this eventfd, and __mem_cgroup_usage_unregister_event ()
   will be called multiple times to delete all events related to this
   eventfd.

The first time __mem_cgroup_usage_unregister_event() is called, the
kernel will clear all items related to this eventfd in thresholds->
primary.

Since there is currently only one eventfd, thresholds-> primary becomes
empty, so the kernel will set thresholds-> primary and hresholds-> spare
to NULL.  If at this time, the user creates a new eventfd and monitor
the memory threshold of this cgroup, kernel will re-initialize
thresholds-> primary.

Then when __mem_cgroup_usage_unregister_event () is called for the
second time, because thresholds-> primary is not empty, the system will
access thresholds-> spare, but thresholds-> spare is NULL, which will
trigger a crash.

In general, the longer it takes to delete all events related to this
eventfd, the easier it is to trigger this problem.

The solution is to check whether the thresholds associated with the
eventfd has been cleared when deleting the event.  If so, we do nothing.

[akpm@linux-foundation.org: fix comment, per Kirill]
Fixes: 907860e ("cgroups: make cftype.unregister_event() void-returning")
Signed-off-by: Chunguang Xu <brookxu@tencent.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/077a6f67-aefa-4591-efec-f2f3af2b0b02@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
commit 9765635 upstream.

This reverts commit:

c54c737 ("drm/dp_mst: Skip validating ports during destruction, just ref")

ugh.

In drm_dp_destroy_connector_work(), we have a pretty good chance of
freeing the actual struct drm_dp_mst_port. However, after destroying
things we send a hotplug through (*mgr->cbs->hotplug)(mgr) which is
where the problems start.

For i915, this calls all the way down to the fbcon probing helpers,
which start trying to access the port in a modeset.

[   45.062001] ==================================================================
[   45.062112] BUG: KASAN: use-after-free in ex_handler_refcount+0x146/0x180
[   45.062196] Write of size 4 at addr ffff8882b4b70968 by task kworker/3:1/53

[   45.062325] CPU: 3 PID: 53 Comm: kworker/3:1 Kdump: loaded Tainted: G           O      4.20.0-rc4Lyude-Test+ #3
[   45.062442] Hardware name: LENOVO 20BWS1KY00/20BWS1KY00, BIOS JBET71WW (1.35 ) 09/14/2018
[   45.062554] Workqueue: events drm_dp_destroy_connector_work [drm_kms_helper]
[   45.062641] Call Trace:
[   45.062685]  dump_stack+0xbd/0x15a
[   45.062735]  ? dump_stack_print_info.cold.0+0x1b/0x1b
[   45.062801]  ? printk+0x9f/0xc5
[   45.062847]  ? kmsg_dump_rewind_nolock+0xe4/0xe4
[   45.062909]  ? ex_handler_refcount+0x146/0x180
[   45.062970]  print_address_description+0x71/0x239
[   45.063036]  ? ex_handler_refcount+0x146/0x180
[   45.063095]  kasan_report.cold.5+0x242/0x30b
[   45.063155]  __asan_report_store4_noabort+0x1c/0x20
[   45.063313]  ex_handler_refcount+0x146/0x180
[   45.063371]  ? ex_handler_clear_fs+0xb0/0xb0
[   45.063428]  fixup_exception+0x98/0xd7
[   45.063484]  ? raw_notifier_call_chain+0x20/0x20
[   45.063548]  do_trap+0x6d/0x210
[   45.063605]  ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[   45.063732]  do_error_trap+0xc0/0x170
[   45.063802]  ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[   45.063929]  do_invalid_op+0x3b/0x50
[   45.063997]  ? _GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[   45.064103]  invalid_op+0x14/0x20
[   45.064162] RIP: 0010:_GLOBAL__sub_I_65535_1_drm_dp_aux_unregister_devnode+0x2f/0x1c6 [drm_kms_helper]
[   45.064274] Code: 00 48 c7 c7 80 fe 53 a0 48 89 e5 e8 5b 6f 26 e1 5d c3 48 8d 0e 0f 0b 48 8d 0b 0f 0b 48 8d 0f 0f 0b 48 8d 0f 0f 0b 49 8d 4d 00 <0f> 0b 49 8d 0e 0f 0b 48 8d 08 0f 0b 49 8d 4d 00 0f 0b 48 8d 0b 0f
[   45.064569] RSP: 0018:ffff8882b789ee10 EFLAGS: 00010282
[   45.064637] RAX: ffff8882af47ae70 RBX: ffff8882af47aa60 RCX: ffff8882b4b70968
[   45.064723] RDX: ffff8882af47ae70 RSI: 0000000000000008 RDI: ffff8882b788bdb8
[   45.064808] RBP: ffff8882b789ee28 R08: ffffed1056f13db4 R09: ffffed1056f13db3
[   45.064894] R10: ffffed1056f13db3 R11: ffff8882b789ed9f R12: ffff8882af47ad28
[   45.064980] R13: ffff8882b4b70968 R14: ffff8882acd86728 R15: ffff8882b4b75dc8
[   45.065084]  drm_dp_mst_reset_vcpi_slots+0x12/0x80 [drm_kms_helper]
[   45.065225]  intel_mst_disable_dp+0xda/0x180 [i915]
[   45.065361]  intel_encoders_disable.isra.107+0x197/0x310 [i915]
[   45.065498]  haswell_crtc_disable+0xbe/0x400 [i915]
[   45.065622]  ? i9xx_disable_plane+0x1c0/0x3e0 [i915]
[   45.065750]  intel_atomic_commit_tail+0x74e/0x3e60 [i915]
[   45.065884]  ? intel_pre_plane_update+0xbc0/0xbc0 [i915]
[   45.065968]  ? drm_atomic_helper_swap_state+0x88b/0x1d90 [drm_kms_helper]
[   45.066054]  ? kasan_check_write+0x14/0x20
[   45.066165]  ? i915_gem_track_fb+0x13a/0x330 [i915]
[   45.066277]  ? i915_sw_fence_complete+0xe9/0x140 [i915]
[   45.066406]  ? __i915_sw_fence_complete+0xc50/0xc50 [i915]
[   45.066540]  intel_atomic_commit+0x72e/0xef0 [i915]
[   45.066635]  ? drm_dev_dbg+0x200/0x200 [drm]
[   45.066764]  ? intel_atomic_commit_tail+0x3e60/0x3e60 [i915]
[   45.066898]  ? intel_atomic_commit_tail+0x3e60/0x3e60 [i915]
[   45.067001]  drm_atomic_commit+0xc4/0xf0 [drm]
[   45.067074]  restore_fbdev_mode_atomic+0x562/0x780 [drm_kms_helper]
[   45.067166]  ? drm_fb_helper_debug_leave+0x690/0x690 [drm_kms_helper]
[   45.067249]  ? kasan_check_read+0x11/0x20
[   45.067324]  restore_fbdev_mode+0x127/0x4b0 [drm_kms_helper]
[   45.067364]  ? kasan_check_read+0x11/0x20
[   45.067406]  drm_fb_helper_restore_fbdev_mode_unlocked+0x164/0x200 [drm_kms_helper]
[   45.067462]  ? drm_fb_helper_hotplug_event+0x30/0x30 [drm_kms_helper]
[   45.067508]  ? kasan_check_write+0x14/0x20
[   45.070360]  ? mutex_unlock+0x22/0x40
[   45.073748]  drm_fb_helper_set_par+0xb2/0xf0 [drm_kms_helper]
[   45.075846]  drm_fb_helper_hotplug_event.part.33+0x1cd/0x290 [drm_kms_helper]
[   45.078088]  drm_fb_helper_hotplug_event+0x1c/0x30 [drm_kms_helper]
[   45.082614]  intel_fbdev_output_poll_changed+0x9f/0x140 [i915]
[   45.087069]  drm_kms_helper_hotplug_event+0x67/0x90 [drm_kms_helper]
[   45.089319]  intel_dp_mst_hotplug+0x37/0x50 [i915]
[   45.091496]  drm_dp_destroy_connector_work+0x510/0x6f0 [drm_kms_helper]
[   45.093675]  ? drm_dp_update_payload_part1+0x1220/0x1220 [drm_kms_helper]
[   45.095851]  ? kasan_check_write+0x14/0x20
[   45.098473]  ? kasan_check_read+0x11/0x20
[   45.101155]  ? strscpy+0x17c/0x530
[   45.103808]  ? __switch_to_asm+0x34/0x70
[   45.106456]  ? syscall_return_via_sysret+0xf/0x7f
[   45.109711]  ? read_word_at_a_time+0x20/0x20
[   45.113138]  ? __switch_to_asm+0x40/0x70
[   45.116529]  ? __switch_to_asm+0x34/0x70
[   45.119891]  ? __switch_to_asm+0x40/0x70
[   45.123224]  ? __switch_to_asm+0x34/0x70
[   45.126540]  ? __switch_to_asm+0x34/0x70
[   45.129824]  process_one_work+0x88d/0x15d0
[   45.133172]  ? pool_mayday_timeout+0x850/0x850
[   45.136459]  ? pci_mmcfg_check_reserved+0x110/0x128
[   45.139739]  ? wake_q_add+0xb0/0xb0
[   45.143010]  ? check_preempt_wakeup+0x652/0x1050
[   45.146304]  ? worker_enter_idle+0x29e/0x740
[   45.149589]  ? __schedule+0x1ec0/0x1ec0
[   45.152937]  ? kasan_check_read+0x11/0x20
[   45.156179]  ? _raw_spin_lock_irq+0xa3/0x130
[   45.159382]  ? _raw_read_unlock_irqrestore+0x30/0x30
[   45.162542]  ? kasan_check_write+0x14/0x20
[   45.165657]  worker_thread+0x1a5/0x1470
[   45.168725]  ? set_load_weight+0x2e0/0x2e0
[   45.171755]  ? process_one_work+0x15d0/0x15d0
[   45.174806]  ? __switch_to_asm+0x34/0x70
[   45.177645]  ? __switch_to_asm+0x40/0x70
[   45.180323]  ? __switch_to_asm+0x34/0x70
[   45.182936]  ? __switch_to_asm+0x40/0x70
[   45.185539]  ? __switch_to_asm+0x34/0x70
[   45.188100]  ? __switch_to_asm+0x40/0x70
[   45.190628]  ? __schedule+0x7d4/0x1ec0
[   45.193143]  ? save_stack+0xa9/0xd0
[   45.195632]  ? kasan_check_write+0x10/0x20
[   45.198162]  ? kasan_kmalloc+0xc4/0xe0
[   45.200609]  ? kmem_cache_alloc_trace+0xdd/0x190
[   45.203046]  ? kthread+0x9f/0x3b0
[   45.205470]  ? ret_from_fork+0x35/0x40
[   45.207876]  ? unwind_next_frame+0x43/0x50
[   45.210273]  ? __save_stack_trace+0x82/0x100
[   45.212658]  ? deactivate_slab.isra.67+0x3d4/0x580
[   45.215026]  ? default_wake_function+0x35/0x50
[   45.217399]  ? kasan_check_read+0x11/0x20
[   45.219825]  ? _raw_spin_lock_irqsave+0xae/0x140
[   45.222174]  ? __lock_text_start+0x8/0x8
[   45.224521]  ? replenish_dl_entity.cold.62+0x4f/0x4f
[   45.226868]  ? __kthread_parkme+0x87/0xf0
[   45.229200]  kthread+0x2f7/0x3b0
[   45.231557]  ? process_one_work+0x15d0/0x15d0
[   45.233923]  ? kthread_park+0x120/0x120
[   45.236249]  ret_from_fork+0x35/0x40

[   45.240875] Allocated by task 242:
[   45.243136]  save_stack+0x43/0xd0
[   45.245385]  kasan_kmalloc+0xc4/0xe0
[   45.247597]  kmem_cache_alloc_trace+0xdd/0x190
[   45.249793]  drm_dp_add_port+0x1e0/0x2170 [drm_kms_helper]
[   45.252000]  drm_dp_send_link_address+0x4a7/0x740 [drm_kms_helper]
[   45.254389]  drm_dp_check_and_send_link_address+0x1a7/0x210 [drm_kms_helper]
[   45.256803]  drm_dp_mst_link_probe_work+0x6f/0xb0 [drm_kms_helper]
[   45.259200]  process_one_work+0x88d/0x15d0
[   45.261597]  worker_thread+0x1a5/0x1470
[   45.264038]  kthread+0x2f7/0x3b0
[   45.266371]  ret_from_fork+0x35/0x40

[   45.270937] Freed by task 53:
[   45.273170]  save_stack+0x43/0xd0
[   45.275382]  __kasan_slab_free+0x139/0x190
[   45.277604]  kasan_slab_free+0xe/0x10
[   45.279826]  kfree+0x99/0x1b0
[   45.282044]  drm_dp_free_mst_port+0x4a/0x60 [drm_kms_helper]
[   45.284330]  drm_dp_destroy_connector_work+0x43e/0x6f0 [drm_kms_helper]
[   45.286660]  process_one_work+0x88d/0x15d0
[   45.288934]  worker_thread+0x1a5/0x1470
[   45.291231]  kthread+0x2f7/0x3b0
[   45.293547]  ret_from_fork+0x35/0x40

[   45.298206] The buggy address belongs to the object at ffff8882b4b70968
                which belongs to the cache kmalloc-2k of size 2048
[   45.303047] The buggy address is located 0 bytes inside of
                2048-byte region [ffff8882b4b70968, ffff8882b4b71168)
[   45.308010] The buggy address belongs to the page:
[   45.310477] page:ffffea000ad2dc00 count:1 mapcount:0 mapping:ffff8882c080cf40 index:0x0 compound_mapcount: 0
[   45.313051] flags: 0x8000000000010200(slab|head)
[   45.315635] raw: 8000000000010200 ffffea000aac2808 ffffea000abe8608 ffff8882c080cf40
[   45.318300] raw: 0000000000000000 00000000000d000d 00000001ffffffff 0000000000000000
[   45.320966] page dumped because: kasan: bad access detected

[   45.326312] Memory state around the buggy address:
[   45.329085]  ffff8882b4b70800: fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   45.331845]  ffff8882b4b70880: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[   45.334584] >ffff8882b4b70900: fc fc fc fc fc fc fc fc fc fc fc fc fc fb fb fb
[   45.337302]                                                           ^
[   45.340061]  ffff8882b4b70980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   45.342910]  ffff8882b4b70a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
[   45.345748] ==================================================================

So, this definitely isn't a fix that we want. This being said; there's
no real easy fix for this problem because of some of the catch-22's of
the MST helpers current design. For starters; we always need to validate
a port with drm_dp_get_validated_port_ref(), but validation relies on
the lifetime of the port in the actual topology. So once the port is
gone, it can't be validated again.

If we were to try to make the payload helpers not use port validation,
then we'd cause another problem: if the port isn't validated, it could
be freed and we'd just start causing more KASAN issues. There are
already hacks that attempt to workaround this in
drm_dp_mst_destroy_connector_work() by re-initializing the kref so that
it can be used again and it's memory can be freed once the VCPI helpers
finish removing the port's respective payloads. But none of these really
do anything helpful since the port still can't be validated since it's
gone from the topology. Also, that workaround is immensely confusing to
read through.

What really needs to be done in order to fix this is to teach DRM how to
track the lifetime of the structs for MST ports and branch devices
separately from their lifetime in the actual topology. Simply put; this
means having two different krefs-one that removes the port/branch device
from the topology, and one that finally calls kfree(). This would let us
simplify things, since we'd now be able to keep ports around without
having to keep them in the topology at the same time, which is exactly
what we need in order to teach our VCPI helpers to only validate ports
when it's actually necessary without running the risk of trying to use
unallocated memory.

Such a fix is on it's way, but for now let's play it safe and just
revert this. If this bug has been around for well over a year, we can
wait a little while to get an actual proper fix here.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: c54c737 ("drm/dp_mst: Skip validating ports during destruction, just ref")
Cc: Daniel Vetter <daniel@ffwll.ch>
Cc: Sean Paul <sean@poorly.run>
Cc: Jerry Zuo <Jerry.Zuo@amd.com>
Cc: Harry Wentland <Harry.Wentland@amd.com>
Cc: stable@vger.kernel.org # v4.6+
Acked-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20181128210005.24434-1-lyude@redhat.com
Cc: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
commit 28936b6 upstream.

inode->i_blocks could be accessed concurrently as noticed by KCSAN,

 BUG: KCSAN: data-race in ext4_do_update_inode [ext4] / inode_add_bytes

 write to 0xffff9a00d4b982d0 of 8 bytes by task 22100 on cpu 118:
  inode_add_bytes+0x65/0xf0
  __inode_add_bytes at fs/stat.c:689
  (inlined by) inode_add_bytes at fs/stat.c:702
  ext4_mb_new_blocks+0x418/0xca0 [ext4]
  ext4_ext_map_blocks+0x1a6b/0x27b0 [ext4]
  ext4_map_blocks+0x1a9/0x950 [ext4]
  _ext4_get_block+0xfc/0x270 [ext4]
  ext4_get_block_unwritten+0x33/0x50 [ext4]
  __block_write_begin_int+0x22e/0xae0
  __block_write_begin+0x39/0x50
  ext4_write_begin+0x388/0xb50 [ext4]
  ext4_da_write_begin+0x35f/0x8f0 [ext4]
  generic_perform_write+0x15d/0x290
  ext4_buffered_write_iter+0x11f/0x210 [ext4]
  ext4_file_write_iter+0xce/0x9e0 [ext4]
  new_sync_write+0x29c/0x3b0
  __vfs_write+0x92/0xa0
  vfs_write+0x103/0x260
  ksys_write+0x9d/0x130
  __x64_sys_write+0x4c/0x60
  do_syscall_64+0x91/0xb05
  entry_SYSCALL_64_after_hwframe+0x49/0xbe

 read to 0xffff9a00d4b982d0 of 8 bytes by task 8 on cpu 65:
  ext4_do_update_inode+0x4a0/0xf60 [ext4]
  ext4_inode_blocks_set at fs/ext4/inode.c:4815
  ext4_mark_iloc_dirty+0xaf/0x160 [ext4]
  ext4_mark_inode_dirty+0x129/0x3e0 [ext4]
  ext4_convert_unwritten_extents+0x253/0x2d0 [ext4]
  ext4_convert_unwritten_io_end_vec+0xc5/0x150 [ext4]
  ext4_end_io_rsv_work+0x22c/0x350 [ext4]
  process_one_work+0x54f/0xb90
  worker_thread+0x80/0x5f0
  kthread+0x1cd/0x1f0
  ret_from_fork+0x27/0x50

 4 locks held by kworker/u256:0/8:
  #0: ffff9a025abc4328 ((wq_completion)ext4-rsv-conversion){+.+.}, at: process_one_work+0x443/0xb90
  #1: ffffab5a862dbe20 ((work_completion)(&ei->i_rsv_conversion_work)){+.+.}, at: process_one_work+0x443/0xb90
  #2: ffff9a025a9d0f58 (jbd2_handle){++++}, at: start_this_handle+0x1c1/0x9d0 [jbd2]
  #3: ffff9a00d4b985d8 (&(&ei->i_raw_lock)->rlock){+.+.}, at: ext4_do_update_inode+0xaa/0xf60 [ext4]
 irq event stamp: 3009267
 hardirqs last  enabled at (3009267): [<ffffffff980da9b7>] __find_get_block+0x107/0x790
 hardirqs last disabled at (3009266): [<ffffffff980da8f9>] __find_get_block+0x49/0x790
 softirqs last  enabled at (3009230): [<ffffffff98a0034c>] __do_softirq+0x34c/0x57c
 softirqs last disabled at (3009223): [<ffffffff97cc67a2>] irq_exit+0xa2/0xc0

 Reported by Kernel Concurrency Sanitizer on:
 CPU: 65 PID: 8 Comm: kworker/u256:0 Tainted: G L 5.6.0-rc2-next-20200221+ #7
 Hardware name: HPE ProLiant DL385 Gen10/ProLiant DL385 Gen10, BIOS A40 07/10/2019
 Workqueue: ext4-rsv-conversion ext4_end_io_rsv_work [ext4]

The plain read is outside of inode->i_lock critical section which
results in a data race. Fix it by adding READ_ONCE() there.

Link: https://lore.kernel.org/r/20200222043258.2279-1-cai@lca.pw
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
[ Upstream commit a866759 ]

This reverts commit 64e62bd.

This commit ends up causing some lockdep splats due to trying to grab the
payload lock while holding the mgr's lock:

[   54.010099]
[   54.011765] ======================================================
[   54.018670] WARNING: possible circular locking dependency detected
[   54.025577] 5.5.0-rc6-02274-g77381c23ee63 torvalds#47 Not tainted
[   54.031610] ------------------------------------------------------
[   54.038516] kworker/1:6/1040 is trying to acquire lock:
[   54.044354] ffff888272af3228 (&mgr->payload_lock){+.+.}, at:
drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.054957]
[   54.054957] but task is already holding lock:
[   54.061473] ffff888272af3060 (&mgr->lock){+.+.}, at:
drm_dp_mst_topology_mgr_set_mst+0x3c/0x2e4
[   54.071193]
[   54.071193] which lock already depends on the new lock.
[   54.071193]
[   54.080334]
[   54.080334] the existing dependency chain (in reverse order) is:
[   54.088697]
[   54.088697] -> #1 (&mgr->lock){+.+.}:
[   54.094440]        __mutex_lock+0xc3/0x498
[   54.099015]        drm_dp_mst_topology_get_port_validated+0x25/0x80
[   54.106018]        drm_dp_update_payload_part1+0xa2/0x2e2
[   54.112051]        intel_mst_pre_enable_dp+0x144/0x18f
[   54.117791]        intel_encoders_pre_enable+0x63/0x70
[   54.123532]        hsw_crtc_enable+0xa1/0x722
[   54.128396]        intel_update_crtc+0x50/0x194
[   54.133455]        skl_commit_modeset_enables+0x40c/0x540
[   54.139485]        intel_atomic_commit_tail+0x5f7/0x130d
[   54.145418]        intel_atomic_commit+0x2c8/0x2d8
[   54.150770]        drm_atomic_helper_set_config+0x5a/0x70
[   54.156801]        drm_mode_setcrtc+0x2ab/0x833
[   54.161862]        drm_ioctl+0x2e5/0x424
[   54.166242]        vfs_ioctl+0x21/0x2f
[   54.170426]        do_vfs_ioctl+0x5fb/0x61e
[   54.175096]        ksys_ioctl+0x55/0x75
[   54.179377]        __x64_sys_ioctl+0x1a/0x1e
[   54.184146]        do_syscall_64+0x5c/0x6d
[   54.188721]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
[   54.194946]
[   54.194946] -> #0 (&mgr->payload_lock){+.+.}:
[   54.201463]
[   54.201463] other info that might help us debug this:
[   54.201463]
[   54.210410]  Possible unsafe locking scenario:
[   54.210410]
[   54.217025]        CPU0                    CPU1
[   54.222082]        ----                    ----
[   54.227138]   lock(&mgr->lock);
[   54.230643]                                lock(&mgr->payload_lock);
[   54.237742]                                lock(&mgr->lock);
[   54.244062]   lock(&mgr->payload_lock);
[   54.248346]
[   54.248346]  *** DEADLOCK ***
[   54.248346]
[   54.254959] 7 locks held by kworker/1:6/1040:
[   54.259822]  #0: ffff888275c4f528 ((wq_completion)events){+.+.},
at: worker_thread+0x455/0x6e2
[   54.269451]  #1: ffffc9000119beb0
((work_completion)(&(&dev_priv->hotplug.hotplug_work)->work)){+.+.},
at: worker_thread+0x455/0x6e2
[   54.282768]  #2: ffff888272a403f0 (&dev->mode_config.mutex){+.+.},
at: i915_hotplug_work_func+0x4b/0x2be
[   54.293368]  #3: ffffffff824fc6c0 (drm_connector_list_iter){.+.+},
at: i915_hotplug_work_func+0x17e/0x2be
[   54.304061]  #4: ffffc9000119bc58 (crtc_ww_class_acquire){+.+.},
at: drm_helper_probe_detect_ctx+0x40/0xfd
[   54.314855]  #5: ffff888272a40470 (crtc_ww_class_mutex){+.+.}, at:
drm_modeset_lock+0x74/0xe2
[   54.324385]  #6: ffff888272af3060 (&mgr->lock){+.+.}, at:
drm_dp_mst_topology_mgr_set_mst+0x3c/0x2e4
[   54.334597]
[   54.334597] stack backtrace:
[   54.339464] CPU: 1 PID: 1040 Comm: kworker/1:6 Not tainted
5.5.0-rc6-02274-g77381c23ee63 torvalds#47
[   54.348893] Hardware name: Google Fizz/Fizz, BIOS
Google_Fizz.10139.39.0 01/04/2018
[   54.357451] Workqueue: events i915_hotplug_work_func
[   54.362995] Call Trace:
[   54.365724]  dump_stack+0x71/0x9c
[   54.369427]  check_noncircular+0x91/0xbc
[   54.373809]  ? __lock_acquire+0xc9e/0xf66
[   54.378286]  ? __lock_acquire+0xc9e/0xf66
[   54.382763]  ? lock_acquire+0x175/0x1ac
[   54.387048]  ? drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.393177]  ? __mutex_lock+0xc3/0x498
[   54.397362]  ? drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.403492]  ? drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.409620]  ? drm_dp_dpcd_access+0xd9/0x101
[   54.414390]  ? drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.420517]  ? drm_dp_mst_topology_mgr_set_mst+0x218/0x2e4
[   54.426645]  ? intel_digital_port_connected+0x34d/0x35c
[   54.432482]  ? intel_dp_detect+0x227/0x44e
[   54.437056]  ? ww_mutex_lock+0x49/0x9a
[   54.441242]  ? drm_helper_probe_detect_ctx+0x75/0xfd
[   54.446789]  ? intel_encoder_hotplug+0x4b/0x97
[   54.451752]  ? intel_ddi_hotplug+0x61/0x2e0
[   54.456423]  ? mark_held_locks+0x53/0x68
[   54.460803]  ? _raw_spin_unlock_irqrestore+0x3a/0x51
[   54.466347]  ? lockdep_hardirqs_on+0x187/0x1a4
[   54.471310]  ? drm_connector_list_iter_next+0x89/0x9a
[   54.476953]  ? i915_hotplug_work_func+0x206/0x2be
[   54.482208]  ? worker_thread+0x4d5/0x6e2
[   54.486587]  ? worker_thread+0x455/0x6e2
[   54.490966]  ? queue_work_on+0x64/0x64
[   54.495151]  ? kthread+0x1e9/0x1f1
[   54.498946]  ? queue_work_on+0x64/0x64
[   54.503130]  ? kthread_unpark+0x5e/0x5e
[   54.507413]  ? ret_from_fork+0x3a/0x50

The proper fix for this is probably cleanup the VCPI allocations when we're
enabling the topology, or on the first payload allocation. For now though,
let's just revert.

Signed-off-by: Lyude Paul <lyude@redhat.com>
Fixes: 64e62bd ("drm/dp_mst: Remove VCPI while disabling topology mgr")
Cc: Sean Paul <sean@poorly.run>
Cc: Wayne Lin <Wayne.Lin@amd.com>
Reviewed-by: Sean Paul <sean@poorly.run>
Link: https://patchwork.freedesktop.org/patch/msgid/20200117205149.97262-1-lyude@redhat.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
commit d3ec10a upstream.

A lockdep circular locking dependency report was seen when running a
keyutils test:

[12537.027242] ======================================================
[12537.059309] WARNING: possible circular locking dependency detected
[12537.088148] 4.18.0-147.7.1.el8_1.x86_64+debug #1 Tainted: G OE    --------- -  -
[12537.125253] ------------------------------------------------------
[12537.153189] keyctl/25598 is trying to acquire lock:
[12537.175087] 000000007c39f96c (&mm->mmap_sem){++++}, at: __might_fault+0xc4/0x1b0
[12537.208365]
[12537.208365] but task is already holding lock:
[12537.234507] 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12537.270476]
[12537.270476] which lock already depends on the new lock.
[12537.270476]
[12537.307209]
[12537.307209] the existing dependency chain (in reverse order) is:
[12537.340754]
[12537.340754] -> #3 (&type->lock_class){++++}:
[12537.367434]        down_write+0x4d/0x110
[12537.385202]        __key_link_begin+0x87/0x280
[12537.405232]        request_key_and_link+0x483/0xf70
[12537.427221]        request_key+0x3c/0x80
[12537.444839]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.468445]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.496731]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.519418]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.546263]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.573551]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.601045]        kthread+0x30c/0x3d0
[12537.617906]        ret_from_fork+0x3a/0x50
[12537.636225]
[12537.636225] -> #2 (root_key_user.cons_lock){+.+.}:
[12537.664525]        __mutex_lock+0x105/0x11f0
[12537.683734]        request_key_and_link+0x35a/0xf70
[12537.705640]        request_key+0x3c/0x80
[12537.723304]        dns_query+0x1db/0x5a5 [dns_resolver]
[12537.746773]        dns_resolve_server_name_to_ip+0x1e1/0x4d0 [cifs]
[12537.775607]        cifs_reconnect+0xe04/0x2500 [cifs]
[12537.798322]        cifs_readv_from_socket+0x461/0x690 [cifs]
[12537.823369]        cifs_read_from_socket+0xa0/0xe0 [cifs]
[12537.847262]        cifs_demultiplex_thread+0x311/0x2db0 [cifs]
[12537.873477]        kthread+0x30c/0x3d0
[12537.890281]        ret_from_fork+0x3a/0x50
[12537.908649]
[12537.908649] -> #1 (&tcp_ses->srv_mutex){+.+.}:
[12537.935225]        __mutex_lock+0x105/0x11f0
[12537.954450]        cifs_call_async+0x102/0x7f0 [cifs]
[12537.977250]        smb2_async_readv+0x6c3/0xc90 [cifs]
[12538.000659]        cifs_readpages+0x120a/0x1e50 [cifs]
[12538.023920]        read_pages+0xf5/0x560
[12538.041583]        __do_page_cache_readahead+0x41d/0x4b0
[12538.067047]        ondemand_readahead+0x44c/0xc10
[12538.092069]        filemap_fault+0xec1/0x1830
[12538.111637]        __do_fault+0x82/0x260
[12538.129216]        do_fault+0x419/0xfb0
[12538.146390]        __handle_mm_fault+0x862/0xdf0
[12538.167408]        handle_mm_fault+0x154/0x550
[12538.187401]        __do_page_fault+0x42f/0xa60
[12538.207395]        do_page_fault+0x38/0x5e0
[12538.225777]        page_fault+0x1e/0x30
[12538.243010]
[12538.243010] -> #0 (&mm->mmap_sem){++++}:
[12538.267875]        lock_acquire+0x14c/0x420
[12538.286848]        __might_fault+0x119/0x1b0
[12538.306006]        keyring_read_iterator+0x7e/0x170
[12538.327936]        assoc_array_subtree_iterate+0x97/0x280
[12538.352154]        keyring_read+0xe9/0x110
[12538.370558]        keyctl_read_key+0x1b9/0x220
[12538.391470]        do_syscall_64+0xa5/0x4b0
[12538.410511]        entry_SYSCALL_64_after_hwframe+0x6a/0xdf
[12538.435535]
[12538.435535] other info that might help us debug this:
[12538.435535]
[12538.472829] Chain exists of:
[12538.472829]   &mm->mmap_sem --> root_key_user.cons_lock --> &type->lock_class
[12538.472829]
[12538.524820]  Possible unsafe locking scenario:
[12538.524820]
[12538.551431]        CPU0                    CPU1
[12538.572654]        ----                    ----
[12538.595865]   lock(&type->lock_class);
[12538.613737]                                lock(root_key_user.cons_lock);
[12538.644234]                                lock(&type->lock_class);
[12538.672410]   lock(&mm->mmap_sem);
[12538.687758]
[12538.687758]  *** DEADLOCK ***
[12538.687758]
[12538.714455] 1 lock held by keyctl/25598:
[12538.732097]  #0: 000000003de5b58d (&type->lock_class){++++}, at: keyctl_read_key+0x15a/0x220
[12538.770573]
[12538.770573] stack backtrace:
[12538.790136] CPU: 2 PID: 25598 Comm: keyctl Kdump: loaded Tainted: G
[12538.844855] Hardware name: HP ProLiant DL360 Gen9/ProLiant DL360 Gen9, BIOS P89 12/27/2015
[12538.881963] Call Trace:
[12538.892897]  dump_stack+0x9a/0xf0
[12538.907908]  print_circular_bug.isra.25.cold.50+0x1bc/0x279
[12538.932891]  ? save_trace+0xd6/0x250
[12538.948979]  check_prev_add.constprop.32+0xc36/0x14f0
[12538.971643]  ? keyring_compare_object+0x104/0x190
[12538.992738]  ? check_usage+0x550/0x550
[12539.009845]  ? sched_clock+0x5/0x10
[12539.025484]  ? sched_clock_cpu+0x18/0x1e0
[12539.043555]  __lock_acquire+0x1f12/0x38d0
[12539.061551]  ? trace_hardirqs_on+0x10/0x10
[12539.080554]  lock_acquire+0x14c/0x420
[12539.100330]  ? __might_fault+0xc4/0x1b0
[12539.119079]  __might_fault+0x119/0x1b0
[12539.135869]  ? __might_fault+0xc4/0x1b0
[12539.153234]  keyring_read_iterator+0x7e/0x170
[12539.172787]  ? keyring_read+0x110/0x110
[12539.190059]  assoc_array_subtree_iterate+0x97/0x280
[12539.211526]  keyring_read+0xe9/0x110
[12539.227561]  ? keyring_gc_check_iterator+0xc0/0xc0
[12539.249076]  keyctl_read_key+0x1b9/0x220
[12539.266660]  do_syscall_64+0xa5/0x4b0
[12539.283091]  entry_SYSCALL_64_after_hwframe+0x6a/0xdf

One way to prevent this deadlock scenario from happening is to not
allow writing to userspace while holding the key semaphore. Instead,
an internal buffer is allocated for getting the keys out from the
read method first before copying them out to userspace without holding
the lock.

That requires taking out the __user modifier from all the relevant
read methods as well as additional changes to not use any userspace
write helpers. That is,

  1) The put_user() call is replaced by a direct copy.
  2) The copy_to_user() call is replaced by memcpy().
  3) All the fault handling code is removed.

Compiling on a x86-64 system, the size of the rxrpc_read() function is
reduced from 3795 bytes to 2384 bytes with this patch.

Fixes: ^1da177e4c3f4 ("Linux-2.6.12-rc2")
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
[ Upstream commit d3296fb ]

We hit following warning when running tests on kernel
compiled with CONFIG_DEBUG_ATOMIC_SLEEP=y:

 WARNING: CPU: 19 PID: 4472 at mm/gup.c:2381 __get_user_pages_fast+0x1a4/0x200
 CPU: 19 PID: 4472 Comm: dummy Not tainted 5.6.0-rc6+ #3
 RIP: 0010:__get_user_pages_fast+0x1a4/0x200
 ...
 Call Trace:
  perf_prepare_sample+0xff1/0x1d90
  perf_event_output_forward+0xe8/0x210
  __perf_event_overflow+0x11a/0x310
  __intel_pmu_pebs_event+0x657/0x850
  intel_pmu_drain_pebs_nhm+0x7de/0x11d0
  handle_pmi_common+0x1b2/0x650
  intel_pmu_handle_irq+0x17b/0x370
  perf_event_nmi_handler+0x40/0x60
  nmi_handle+0x192/0x590
  default_do_nmi+0x6d/0x150
  do_nmi+0x2f9/0x3c0
  nmi+0x8e/0xd7

While __get_user_pages_fast() is IRQ-safe, it calls access_ok(),
which warns on:

  WARN_ON_ONCE(!in_task() && !pagefault_disabled())

Peter suggested disabling page faults around __get_user_pages_fast(),
which gets rid of the warning in access_ok() call.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200407141427.3184722-1-jolsa@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
commit 10a98cb upstream.

Leaving PF_MEMALLOC set when exiting a kthread causes it to remain set
during do_exit().  That can confuse things.  In particular, if BSD
process accounting is enabled, then do_exit() writes data to an
accounting file.  If that file has FS_SYNC_FL set, then this write
occurs synchronously and can misbehave if PF_MEMALLOC is set.

For example, if the accounting file is located on an XFS filesystem,
then a WARN_ON_ONCE() in iomap_do_writepage() is triggered and the data
doesn't get written when it should.  Or if the accounting file is
located on an ext4 filesystem without a journal, then a WARN_ON_ONCE()
in ext4_write_inode() is triggered and the inode doesn't get written.

Fix this in xfsaild() by using the helper functions to save and restore
PF_MEMALLOC.

This can be reproduced as follows in the kvm-xfstests test appliance
modified to add the 'acct' Debian package, and with kvm-xfstests's
recommended kconfig modified to add CONFIG_BSD_PROCESS_ACCT=y:

        mkfs.xfs -f /dev/vdb
        mount /vdb
        touch /vdb/file
        chattr +S /vdb/file
        accton /vdb/file
        mkfs.xfs -f /dev/vdc
        mount /vdc
        umount /vdc

It causes:
	WARNING: CPU: 1 PID: 336 at fs/iomap/buffered-io.c:1534
	CPU: 1 PID: 336 Comm: xfsaild/vdc Not tainted 5.6.0-rc5 #3
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191223_100556-anatol 04/01/2014
	RIP: 0010:iomap_do_writepage+0x16b/0x1f0 fs/iomap/buffered-io.c:1534
	[...]
	Call Trace:
	 write_cache_pages+0x189/0x4d0 mm/page-writeback.c:2238
	 iomap_writepages+0x1c/0x33 fs/iomap/buffered-io.c:1642
	 xfs_vm_writepages+0x65/0x90 fs/xfs/xfs_aops.c:578
	 do_writepages+0x41/0xe0 mm/page-writeback.c:2344
	 __filemap_fdatawrite_range+0xd2/0x120 mm/filemap.c:421
	 file_write_and_wait_range+0x71/0xc0 mm/filemap.c:760
	 xfs_file_fsync+0x7a/0x2b0 fs/xfs/xfs_file.c:114
	 generic_write_sync include/linux/fs.h:2867 [inline]
	 xfs_file_buffered_aio_write+0x379/0x3b0 fs/xfs/xfs_file.c:691
	 call_write_iter include/linux/fs.h:1901 [inline]
	 new_sync_write+0x130/0x1d0 fs/read_write.c:483
	 __kernel_write+0x54/0xe0 fs/read_write.c:515
	 do_acct_process+0x122/0x170 kernel/acct.c:522
	 slow_acct_process kernel/acct.c:581 [inline]
	 acct_process+0x1d4/0x27c kernel/acct.c:607
	 do_exit+0x83d/0xbc0 kernel/exit.c:791
	 kthread+0xf1/0x140 kernel/kthread.c:257
	 ret_from_fork+0x27/0x50 arch/x86/entry/entry_64.S:352

This bug was originally reported by syzbot at
https://lore.kernel.org/r/0000000000000e7156059f751d7b@google.com.

Reported-by: syzbot+1f9dc49e8de2582d90c2@syzkaller.appspotmail.com
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
commit 5cbf326 upstream.

Use follow_pfn() to get the PFN of a PFNMAP VMA instead of assuming that
vma->vm_pgoff holds the base PFN of the VMA.  This fixes a bug where
attempting to do VFIO_IOMMU_MAP_DMA on an arbitrary PFNMAP'd region of
memory calculates garbage for the PFN.

Hilariously, this only got detected because the first "PFN" calculated
by vaddr_get_pfn() is PFN 0 (vma->vm_pgoff==0), and iommu_iova_to_phys()
uses PA==0 as an error, which triggers a WARN in vfio_unmap_unpin()
because the translation "failed".  PFN 0 is now unconditionally reserved
on x86 in order to mitigate L1TF, which causes is_invalid_reserved_pfn()
to return true and in turns results in vaddr_get_pfn() returning success
for PFN 0.  Eventually the bogus calculation runs into PFNs that aren't
reserved and leads to failure in vfio_pin_map_dma().  The subsequent
call to vfio_remove_dma() attempts to unmap PFN 0 and WARNs.

  WARNING: CPU: 8 PID: 5130 at drivers/vfio/vfio_iommu_type1.c:750 vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1]
  Modules linked in: vfio_pci vfio_virqfd vfio_iommu_type1 vfio ...
  CPU: 8 PID: 5130 Comm: sgx Tainted: G        W         5.6.0-rc5-705d787c7fee-vfio+ #3
  Hardware name: Intel Corporation Mehlow UP Server Platform/Moss Beach Server, BIOS CNLSE2R1.D00.X119.B49.1803010910 03/01/2018
  RIP: 0010:vfio_unmap_unpin+0x2e1/0x310 [vfio_iommu_type1]
  Code: <0f> 0b 49 81 c5 00 10 00 00 e9 c5 fe ff ff bb 00 10 00 00 e9 3d fe
  RSP: 0018:ffffbeb5039ebda8 EFLAGS: 00010246
  RAX: 0000000000000000 RBX: ffff9a55cbf8d480 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff9a52b771c200
  RBP: 0000000000000000 R08: 0000000000000040 R09: 00000000fffffff2
  R10: 0000000000000001 R11: ffff9a51fa896000 R12: 0000000184010000
  R13: 0000000184000000 R14: 0000000000010000 R15: ffff9a55cb66ea08
  FS:  00007f15d3830b40(0000) GS:ffff9a55d5600000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000561cf39429e0 CR3: 000000084f75f005 CR4: 00000000003626e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   vfio_remove_dma+0x17/0x70 [vfio_iommu_type1]
   vfio_iommu_type1_ioctl+0x9e3/0xa7b [vfio_iommu_type1]
   ksys_ioctl+0x92/0xb0
   __x64_sys_ioctl+0x16/0x20
   do_syscall_64+0x4c/0x180
   entry_SYSCALL_64_after_hwframe+0x44/0xa9
  RIP: 0033:0x7f15d04c75d7
  Code: <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 81 48 2d 00 f7 d8 64 89 01 48

Fixes: 73fa0d1 ("vfio: Type1 IOMMU implementation")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Jun 22, 2020
…f fs_info::journal_info

commit fcc9973 upstream.

[BUG]
One run of btrfs/063 triggered the following lockdep warning:
  ============================================
  WARNING: possible recursive locking detected
  5.6.0-rc7-custom+ torvalds#48 Not tainted
  --------------------------------------------
  kworker/u24:0/7 is trying to acquire lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

  but task is already holding lock:
  ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]

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

         CPU0
         ----
    lock(sb_internal#2);
    lock(sb_internal#2);

   *** DEADLOCK ***

   May be due to missing lock nesting notation

  4 locks held by kworker/u24:0/7:
   #0: ffff88817b495948 ((wq_completion)btrfs-endio-write){+.+.}, at: process_one_work+0x557/0xb80
   #1: ffff888189ea7db8 ((work_completion)(&work->normal_work)){+.+.}, at: process_one_work+0x557/0xb80
   #2: ffff88817d3a46e0 (sb_internal#2){.+.+}, at: start_transaction+0x66c/0x890 [btrfs]
   #3: ffff888174ca4da8 (&fs_info->reloc_mutex){+.+.}, at: btrfs_record_root_in_trans+0x83/0xd0 [btrfs]

  stack backtrace:
  CPU: 0 PID: 7 Comm: kworker/u24:0 Not tainted 5.6.0-rc7-custom+ torvalds#48
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
  Workqueue: btrfs-endio-write btrfs_work_helper [btrfs]
  Call Trace:
   dump_stack+0xc2/0x11a
   __lock_acquire.cold+0xce/0x214
   lock_acquire+0xe6/0x210
   __sb_start_write+0x14e/0x290
   start_transaction+0x66c/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   find_free_extent+0x1504/0x1a50 [btrfs]
   btrfs_reserve_extent+0xd5/0x1f0 [btrfs]
   btrfs_alloc_tree_block+0x1ac/0x570 [btrfs]
   btrfs_copy_root+0x213/0x580 [btrfs]
   create_reloc_root+0x3bd/0x470 [btrfs]
   btrfs_init_reloc_root+0x2d2/0x310 [btrfs]
   record_root_in_trans+0x191/0x1d0 [btrfs]
   btrfs_record_root_in_trans+0x90/0xd0 [btrfs]
   start_transaction+0x16e/0x890 [btrfs]
   btrfs_join_transaction+0x1d/0x20 [btrfs]
   btrfs_finish_ordered_io+0x55d/0xcd0 [btrfs]
   finish_ordered_fn+0x15/0x20 [btrfs]
   btrfs_work_helper+0x116/0x9a0 [btrfs]
   process_one_work+0x632/0xb80
   worker_thread+0x80/0x690
   kthread+0x1a3/0x1f0
   ret_from_fork+0x27/0x50

It's pretty hard to reproduce, only one hit so far.

[CAUSE]
This is because we're calling btrfs_join_transaction() without re-using
the current running one:

btrfs_finish_ordered_io()
|- btrfs_join_transaction()		<<< Call #1
   |- btrfs_record_root_in_trans()
      |- btrfs_reserve_extent()
	 |- btrfs_join_transaction()	<<< Call #2

Normally such btrfs_join_transaction() call should re-use the existing
one, without trying to re-start a transaction.

But the problem is, in btrfs_join_transaction() call #1, we call
btrfs_record_root_in_trans() before initializing current::journal_info.

And in btrfs_join_transaction() call #2, we're relying on
current::journal_info to avoid such deadlock.

[FIX]
Call btrfs_record_root_in_trans() after we have initialized
current::journal_info.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Sep 25, 2020
commit 0bd0db4 upstream.

The `INSN_CONFIG` comedi instruction with sub-instruction code
`INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is
used as a right shift amount for other bitmask values without being
checked.  Shift amounts greater than or equal to 32 will result in
undefined behavior.  Add code to deal with this.

Fixes: 33cdce6 ("staging: comedi: addi_apci_1032: conform to new INSN_CONFIG_DIGITAL_TRIG")
Cc: <stable@vger.kernel.org> #3.8+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20200717145257.112660-3-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Sep 25, 2020
commit 926234f upstream.

The `INSN_CONFIG` comedi instruction with sub-instruction code
`INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is
used as a right shift amount for other bitmask values without being
checked.  Shift amounts greater than or equal to 32 will result in
undefined behavior.  Add code to deal with this.

Fixes: 1e15687 ("staging: comedi: addi_apci_1564: add Change-of-State interrupt subdevice and required functions")
Cc: <stable@vger.kernel.org> #3.17+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20200717145257.112660-4-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Sep 25, 2020
commit be6577a upstream.

Stalls are quite frequent with recent kernels. I enabled
CONFIG_SOFTLOCKUP_DETECTOR and I caught the following stall:

watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [cc1:22803]
CPU: 0 PID: 22803 Comm: cc1 Not tainted 5.6.17+ #3
Hardware name: 9000/800/rp3440
 IAOQ[0]: d_alloc_parallel+0x384/0x688
 IAOQ[1]: d_alloc_parallel+0x388/0x688
 RP(r2): d_alloc_parallel+0x134/0x688
Backtrace:
 [<000000004036974c>] __lookup_slow+0xa4/0x200
 [<0000000040369fc8>] walk_component+0x288/0x458
 [<000000004036a9a0>] path_lookupat+0x88/0x198
 [<000000004036e748>] filename_lookup+0xa0/0x168
 [<000000004036e95c>] user_path_at_empty+0x64/0x80
 [<000000004035d93c>] vfs_statx+0x104/0x158
 [<000000004035dfcc>] __do_sys_lstat64+0x44/0x80
 [<000000004035e5a0>] sys_lstat64+0x20/0x38
 [<0000000040180054>] syscall_exit+0x0/0x14

The code was stuck in this loop in d_alloc_parallel:

    4037d414:   0e 00 10 dc     ldd 0(r16),ret0
    4037d418:   c7 fc 5f ed     bb,< ret0,1f,4037d414 <d_alloc_parallel+0x384>
    4037d41c:   08 00 02 40     nop

This is the inner loop of bit_spin_lock which is called by hlist_bl_unlock in
d_alloc_parallel:

static inline void bit_spin_lock(int bitnum, unsigned long *addr)
{
        /*
         * Assuming the lock is uncontended, this never enters
         * the body of the outer loop. If it is contended, then
         * within the inner loop a non-atomic test is used to
         * busywait with less bus contention for a good time to
         * attempt to acquire the lock bit.
         */
        preempt_disable();
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
        while (unlikely(test_and_set_bit_lock(bitnum, addr))) {
                preempt_enable();
                do {
                        cpu_relax();
                } while (test_bit(bitnum, addr));
                preempt_disable();
        }
#endif
        __acquire(bitlock);
}

After consideration, I realized that we must be losing bit unlocks.
Then, I noticed that we missed defining atomic64_set_release().
Adding this define fixes the stalls in bit operations.

Signed-off-by: Dave Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
ADESTM pushed a commit that referenced this pull request Sep 25, 2020
[ Upstream commit e24c644 ]

I compiled with AddressSanitizer and I had these memory leaks while I
was using the tep_parse_format function:

    Direct leak of 28 byte(s) in 4 object(s) allocated from:
        #0 0x7fb07db49ffe in __interceptor_realloc (/lib/x86_64-linux-gnu/libasan.so.5+0x10dffe)
        #1 0x7fb07a724228 in extend_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:985
        #2 0x7fb07a724c21 in __read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1140
        #3 0x7fb07a724f78 in read_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1206
        #4 0x7fb07a725191 in __read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1291
        #5 0x7fb07a7251df in read_expect_type /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1299
        #6 0x7fb07a72e6c8 in process_dynamic_array_len /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:2849
        #7 0x7fb07a7304b8 in process_function /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3161
        #8 0x7fb07a730900 in process_arg_token /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3207
        #9 0x7fb07a727c0b in process_arg /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:1786
        #10 0x7fb07a731080 in event_read_print_args /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3285
        #11 0x7fb07a731722 in event_read_print /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:3369
        #12 0x7fb07a740054 in __tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6335
        #13 0x7fb07a74047a in __parse_event /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6389
        #14 0x7fb07a740536 in tep_parse_format /home/pduplessis/repo/linux/tools/lib/traceevent/event-parse.c:6431
        #15 0x7fb07a785acf in parse_event ../../../src/fs-src/fs.c:251
        #16 0x7fb07a785ccd in parse_systems ../../../src/fs-src/fs.c:284
        #17 0x7fb07a786fb3 in read_metadata ../../../src/fs-src/fs.c:593
        #18 0x7fb07a78760e in ftrace_fs_source_init ../../../src/fs-src/fs.c:727
        #19 0x7fb07d90c19c in add_component_with_init_method_data ../../../../src/lib/graph/graph.c:1048
        #20 0x7fb07d90c87b in add_source_component_with_initialize_method_data ../../../../src/lib/graph/graph.c:1127
        #21 0x7fb07d90c92a in bt_graph_add_source_component ../../../../src/lib/graph/graph.c:1152
        #22 0x55db11aa632e in cmd_run_ctx_create_components_from_config_components ../../../src/cli/babeltrace2.c:2252
        #23 0x55db11aa6fda in cmd_run_ctx_create_components ../../../src/cli/babeltrace2.c:2347
        #24 0x55db11aa780c in cmd_run ../../../src/cli/babeltrace2.c:2461
        torvalds#25 0x55db11aa8a7d in main ../../../src/cli/babeltrace2.c:2673
        torvalds#26 0x7fb07d5460b2 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+0x270b2)

The token variable in the process_dynamic_array_len function is
allocated in the read_expect_type function, but is not freed before
calling the read_token function.

Free the token variable before calling read_token in order to plug the
leak.

Signed-off-by: Philippe Duplessis-Guindon <pduplessis@efficios.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/linux-trace-devel/20200730150236.5392-1-pduplessis@efficios.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
ADESTM pushed a commit that referenced this pull request Sep 25, 2020
commit 18c850f upstream.

There's long existed a lockdep splat because we open our bdev's under
the ->device_list_mutex at mount time, which acquires the bd_mutex.
Usually this goes unnoticed, but if you do loopback devices at all
suddenly the bd_mutex comes with a whole host of other dependencies,
which results in the splat when you mount a btrfs file system.

======================================================
WARNING: possible circular locking dependency detected
5.8.0-0.rc3.1.fc33.x86_64+debug #1 Not tainted
------------------------------------------------------
systemd-journal/509 is trying to acquire lock:
ffff970831f84db0 (&fs_info->reloc_mutex){+.+.}-{3:3}, at: btrfs_record_root_in_trans+0x44/0x70 [btrfs]

but task is already holding lock:
ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs]

which lock already depends on the new lock.

the existing dependency chain (in reverse order) is:

 -> #6 (sb_pagefaults){.+.+}-{0:0}:
       __sb_start_write+0x13e/0x220
       btrfs_page_mkwrite+0x59/0x560 [btrfs]
       do_page_mkwrite+0x4f/0x130
       do_wp_page+0x3b0/0x4f0
       handle_mm_fault+0xf47/0x1850
       do_user_addr_fault+0x1fc/0x4b0
       exc_page_fault+0x88/0x300
       asm_exc_page_fault+0x1e/0x30

 -> #5 (&mm->mmap_lock#2){++++}-{3:3}:
       __might_fault+0x60/0x80
       _copy_from_user+0x20/0xb0
       get_sg_io_hdr+0x9a/0xb0
       scsi_cmd_ioctl+0x1ea/0x2f0
       cdrom_ioctl+0x3c/0x12b4
       sr_block_ioctl+0xa4/0xd0
       block_ioctl+0x3f/0x50
       ksys_ioctl+0x82/0xc0
       __x64_sys_ioctl+0x16/0x20
       do_syscall_64+0x52/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

 -> #4 (&cd->lock){+.+.}-{3:3}:
       __mutex_lock+0x7b/0x820
       sr_block_open+0xa2/0x180
       __blkdev_get+0xdd/0x550
       blkdev_get+0x38/0x150
       do_dentry_open+0x16b/0x3e0
       path_openat+0x3c9/0xa00
       do_filp_open+0x75/0x100
       do_sys_openat2+0x8a/0x140
       __x64_sys_openat+0x46/0x70
       do_syscall_64+0x52/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

 -> #3 (&bdev->bd_mutex){+.+.}-{3:3}:
       __mutex_lock+0x7b/0x820
       __blkdev_get+0x6a/0x550
       blkdev_get+0x85/0x150
       blkdev_get_by_path+0x2c/0x70
       btrfs_get_bdev_and_sb+0x1b/0xb0 [btrfs]
       open_fs_devices+0x88/0x240 [btrfs]
       btrfs_open_devices+0x92/0xa0 [btrfs]
       btrfs_mount_root+0x250/0x490 [btrfs]
       legacy_get_tree+0x30/0x50
       vfs_get_tree+0x28/0xc0
       vfs_kern_mount.part.0+0x71/0xb0
       btrfs_mount+0x119/0x380 [btrfs]
       legacy_get_tree+0x30/0x50
       vfs_get_tree+0x28/0xc0
       do_mount+0x8c6/0xca0
       __x64_sys_mount+0x8e/0xd0
       do_syscall_64+0x52/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

 -> #2 (&fs_devs->device_list_mutex){+.+.}-{3:3}:
       __mutex_lock+0x7b/0x820
       btrfs_run_dev_stats+0x36/0x420 [btrfs]
       commit_cowonly_roots+0x91/0x2d0 [btrfs]
       btrfs_commit_transaction+0x4e6/0x9f0 [btrfs]
       btrfs_sync_file+0x38a/0x480 [btrfs]
       __x64_sys_fdatasync+0x47/0x80
       do_syscall_64+0x52/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

 -> #1 (&fs_info->tree_log_mutex){+.+.}-{3:3}:
       __mutex_lock+0x7b/0x820
       btrfs_commit_transaction+0x48e/0x9f0 [btrfs]
       btrfs_sync_file+0x38a/0x480 [btrfs]
       __x64_sys_fdatasync+0x47/0x80
       do_syscall_64+0x52/0xb0
       entry_SYSCALL_64_after_hwframe+0x44/0xa9

 -> #0 (&fs_info->reloc_mutex){+.+.}-{3:3}:
       __lock_acquire+0x1241/0x20c0
       lock_acquire+0xb0/0x400
       __mutex_lock+0x7b/0x820
       btrfs_record_root_in_trans+0x44/0x70 [btrfs]
       start_transaction+0xd2/0x500 [btrfs]
       btrfs_dirty_inode+0x44/0xd0 [btrfs]
       file_update_time+0xc6/0x120
       btrfs_page_mkwrite+0xda/0x560 [btrfs]
       do_page_mkwrite+0x4f/0x130
       do_wp_page+0x3b0/0x4f0
       handle_mm_fault+0xf47/0x1850
       do_user_addr_fault+0x1fc/0x4b0
       exc_page_fault+0x88/0x300
       asm_exc_page_fault+0x1e/0x30

other info that might help us debug this:

Chain exists of:
  &fs_info->reloc_mutex --> &mm->mmap_lock#2 --> sb_pagefaults

Possible unsafe locking scenario:

     CPU0                    CPU1
     ----                    ----
 lock(sb_pagefaults);
                             lock(&mm->mmap_lock#2);
                             lock(sb_pagefaults);
 lock(&fs_info->reloc_mutex);

 *** DEADLOCK ***

3 locks held by systemd-journal/509:
 #0: ffff97083bdec8b8 (&mm->mmap_lock#2){++++}-{3:3}, at: do_user_addr_fault+0x12e/0x4b0
 #1: ffff97083144d598 (sb_pagefaults){.+.+}-{0:0}, at: btrfs_page_mkwrite+0x59/0x560 [btrfs]
 #2: ffff97083144d6a8 (sb_internal){.+.+}-{0:0}, at: start_transaction+0x3f8/0x500 [btrfs]

stack backtrace:
CPU: 0 PID: 509 Comm: systemd-journal Not tainted 5.8.0-0.rc3.1.fc33.x86_64+debug #1
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 0.0.0 02/06/2015
Call Trace:
 dump_stack+0x92/0xc8
 check_noncircular+0x134/0x150
 __lock_acquire+0x1241/0x20c0
 lock_acquire+0xb0/0x400
 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
 ? lock_acquire+0xb0/0x400
 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
 __mutex_lock+0x7b/0x820
 ? btrfs_record_root_in_trans+0x44/0x70 [btrfs]
 ? kvm_sched_clock_read+0x14/0x30
 ? sched_clock+0x5/0x10
 ? sched_clock_cpu+0xc/0xb0
 btrfs_record_root_in_trans+0x44/0x70 [btrfs]
 start_transaction+0xd2/0x500 [btrfs]
 btrfs_dirty_inode+0x44/0xd0 [btrfs]
 file_update_time+0xc6/0x120
 btrfs_page_mkwrite+0xda/0x560 [btrfs]
 ? sched_clock+0x5/0x10
 do_page_mkwrite+0x4f/0x130
 do_wp_page+0x3b0/0x4f0
 handle_mm_fault+0xf47/0x1850
 do_user_addr_fault+0x1fc/0x4b0
 exc_page_fault+0x88/0x300
 ? asm_exc_page_fault+0x8/0x30
 asm_exc_page_fault+0x1e/0x30
RIP: 0033:0x7fa3972fdbfe
Code: Bad RIP value.

Fix this by not holding the ->device_list_mutex at this point.  The
device_list_mutex exists to protect us from modifying the device list
while the file system is running.

However it can also be modified by doing a scan on a device.  But this
action is specifically protected by the uuid_mutex, which we are holding
here.  We cannot race with opening at this point because we have the
->s_mount lock held during the mount.  Not having the
->device_list_mutex here is perfectly safe as we're not going to change
the devices at this point.

CC: stable@vger.kernel.org # 4.19+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
[ add some comments ]
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
atorgue added a commit that referenced this pull request Nov 2, 2020
Mutex protection in not needed in _allocate_opp_table as it this function
is already called under mutex lock. Furthermore, it fixes the following
issue seen with CONFIG_PROVE_LOCKING flag:

[    3.648912] =========================
[    3.648927] WARNING: held lock freed!
[    3.648944] 5.4.56-00014-g7cc4a3bdec16 #7 Not tainted
[    3.648957] -------------------------
[    3.648976] kworker/1:1/22 is freeing memory df183c00-df183fff, with a lock still held there!
[    3.648991] df183ca0 (&opp_table->lock){+.+.}, at: _opp_get_opp_table+0x1cc/0x224
[    3.649037] 5 locks held by kworker/1:1/22:
[    3.649049]  #0: df0086a0 ((wq_completion)events){+.+.}, at: process_one_work+0x200/0x858
[    3.649082]  #1: df515f1c (deferred_probe_work){+.+.}, at: process_one_work+0x200/0x858
[    3.649110]  #2: d1ff08cc (&dev->mutex){....}, at: __device_attach+0x34/0x17c
[    3.649145]  #3: c139e5e0 (opp_table_lock){+.+.}, at: _opp_get_opp_table+0x1c/0x224
[    3.649175]  #4: df183ca0 (&opp_table->lock){+.+.}, at: _opp_get_opp_table+0x1cc/0x224

Fixes: cf1f361 ("opp: core: fix memory leak in probe deferral")

Signed-off-by: Alexandre Torgue <alexandre.torgue@st.com>
Change-Id: I6da51fab26b698bb803a3a8ddf5454f73d8af956
Reviewed-on: https://gerrit.st.com/c/mpu/oe/st/linux-stm32/+/178474
Reviewed-by: CITOOLS <smet-aci-reviews@lists.codex.cro.st.com>
stalyatech pushed a commit to stalyatech/linux that referenced this pull request Feb 26, 2021
[ Upstream commit c312446 ]

The mpath disk node takes a reference on the request mpath
request queue when adding live path to the mpath gendisk.
However if we connected to an inaccessible path device_add_disk
is not called, so if we disconnect and remove the mpath gendisk
we endup putting an reference on the request queue that was
never taken [1].

Fix that to check if we ever added a live path (using
NVME_NS_HEAD_HAS_DISK flag) and if not, clear the disk->queue
reference.

[1]:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 1372 at lib/refcount.c:28 refcount_warn_saturate+0xa6/0xf0
CPU: 1 PID: 1372 Comm: nvme Tainted: G           O      5.7.0-rc2+ STMicroelectronics#3
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.13.0-1ubuntu1 04/01/2014
RIP: 0010:refcount_warn_saturate+0xa6/0xf0
RSP: 0018:ffffb29e8053bdc0 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8b7a2f4fc060 RCX: 0000000000000007
RDX: 0000000000000007 RSI: 0000000000000092 RDI: ffff8b7a3ec99980
RBP: ffff8b7a2f4fc000 R08: 00000000000002e1 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000
R13: fffffffffffffff2 R14: ffffb29e8053bf08 R15: ffff8b7a320e2da0
FS:  00007f135d4ca800(0000) GS:ffff8b7a3ec80000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005651178c0c30 CR3: 000000003b650005 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 disk_release+0xa2/0xc0
 device_release+0x28/0x80
 kobject_put+0xa5/0x1b0
 nvme_put_ns_head+0x26/0x70 [nvme_core]
 nvme_put_ns+0x30/0x60 [nvme_core]
 nvme_remove_namespaces+0x9b/0xe0 [nvme_core]
 nvme_do_delete_ctrl+0x43/0x5c [nvme_core]
 nvme_sysfs_delete.cold+0x8/0xd [nvme_core]
 kernfs_fop_write+0xc1/0x1a0
 vfs_write+0xb6/0x1a0
 ksys_write+0x5f/0xe0
 do_syscall_64+0x52/0x1a0
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported-by: Anton Eidelman <anton@lightbitslabs.com>
Tested-by: Anton Eidelman <anton@lightbitslabs.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
stalyatech pushed a commit to stalyatech/linux that referenced this pull request Feb 26, 2021
commit 0bd0db4 upstream.

The `INSN_CONFIG` comedi instruction with sub-instruction code
`INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is
used as a right shift amount for other bitmask values without being
checked.  Shift amounts greater than or equal to 32 will result in
undefined behavior.  Add code to deal with this.

Fixes: 33cdce6 ("staging: comedi: addi_apci_1032: conform to new INSN_CONFIG_DIGITAL_TRIG")
Cc: <stable@vger.kernel.org> STMicroelectronics#3.8+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20200717145257.112660-3-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
stalyatech pushed a commit to stalyatech/linux that referenced this pull request Feb 26, 2021
commit 926234f upstream.

The `INSN_CONFIG` comedi instruction with sub-instruction code
`INSN_CONFIG_DIGITAL_TRIG` includes a base channel in `data[3]`. This is
used as a right shift amount for other bitmask values without being
checked.  Shift amounts greater than or equal to 32 will result in
undefined behavior.  Add code to deal with this.

Fixes: 1e15687 ("staging: comedi: addi_apci_1564: add Change-of-State interrupt subdevice and required functions")
Cc: <stable@vger.kernel.org> STMicroelectronics#3.17+
Signed-off-by: Ian Abbott <abbotti@mev.co.uk>
Link: https://lore.kernel.org/r/20200717145257.112660-4-abbotti@mev.co.uk
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
stalyatech pushed a commit to stalyatech/linux that referenced this pull request Feb 26, 2021
commit be6577a upstream.

Stalls are quite frequent with recent kernels. I enabled
CONFIG_SOFTLOCKUP_DETECTOR and I caught the following stall:

watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [cc1:22803]
CPU: 0 PID: 22803 Comm: cc1 Not tainted 5.6.17+ STMicroelectronics#3
Hardware name: 9000/800/rp3440
 IAOQ[0]: d_alloc_parallel+0x384/0x688
 IAOQ[1]: d_alloc_parallel+0x388/0x688
 RP(r2): d_alloc_parallel+0x134/0x688
Backtrace:
 [<000000004036974c>] __lookup_slow+0xa4/0x200
 [<0000000040369fc8>] walk_component+0x288/0x458
 [<000000004036a9a0>] path_lookupat+0x88/0x198
 [<000000004036e748>] filename_lookup+0xa0/0x168
 [<000000004036e95c>] user_path_at_empty+0x64/0x80
 [<000000004035d93c>] vfs_statx+0x104/0x158
 [<000000004035dfcc>] __do_sys_lstat64+0x44/0x80
 [<000000004035e5a0>] sys_lstat64+0x20/0x38
 [<0000000040180054>] syscall_exit+0x0/0x14

The code was stuck in this loop in d_alloc_parallel:

    4037d414:   0e 00 10 dc     ldd 0(r16),ret0
    4037d418:   c7 fc 5f ed     bb,< ret0,1f,4037d414 <d_alloc_parallel+0x384>
    4037d41c:   08 00 02 40     nop

This is the inner loop of bit_spin_lock which is called by hlist_bl_unlock in
d_alloc_parallel:

static inline void bit_spin_lock(int bitnum, unsigned long *addr)
{
        /*
         * Assuming the lock is uncontended, this never enters
         * the body of the outer loop. If it is contended, then
         * within the inner loop a non-atomic test is used to
         * busywait with less bus contention for a good time to
         * attempt to acquire the lock bit.
         */
        preempt_disable();
#if defined(CONFIG_SMP) || defined(CONFIG_DEBUG_SPINLOCK)
        while (unlikely(test_and_set_bit_lock(bitnum, addr))) {
                preempt_enable();
                do {
                        cpu_relax();
                } while (test_bit(bitnum, addr));
                preempt_disable();
        }
#endif
        __acquire(bitlock);
}

After consideration, I realized that we must be losing bit unlocks.
Then, I noticed that we missed defining atomic64_set_release().
Adding this define fixes the stalls in bit operations.

Signed-off-by: Dave Anglin <dave.anglin@bell.net>
Cc: stable@vger.kernel.org
Signed-off-by: Helge Deller <deller@gmx.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arnopo pushed a commit to arnopo/linux that referenced this pull request Mar 14, 2022
With CONFIG_FORTIFY_SOURCE enabled, string functions will also perform
dynamic checks using __builtin_object_size(ptr), which when failed will
panic the kernel.

Because the KASAN test deliberately performs out-of-bounds operations,
the kernel panics with FORTIFY_SOURCE, for example:

 | kernel BUG at lib/string_helpers.c:910!
 | invalid opcode: 0000 [STMicroelectronics#1] PREEMPT SMP KASAN PTI
 | CPU: 1 PID: 137 Comm: kunit_try_catch Tainted: G    B             5.16.0-rc3+ STMicroelectronics#3
 | Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.14.0-2 04/01/2014
 | RIP: 0010:fortify_panic+0x19/0x1b
 | ...
 | Call Trace:
 |  kmalloc_oob_in_memset.cold+0x16/0x16
 |  ...

Fix it by also hiding `ptr` from the optimizer, which will ensure that
__builtin_object_size() does not return a valid size, preventing
fortified string functions from panicking.

Link: https://lkml.kernel.org/r/20220124160744.1244685-1-elver@google.com
Signed-off-by: Marco Elver <elver@google.com>
Reported-by: Nico Pache <npache@redhat.com>
Reviewed-by: Nico Pache <npache@redhat.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
dponchalee pushed a commit to dponchalee/linux-st that referenced this pull request Feb 2, 2023
commit 9c6d778 upstream.

Automatic kernel fuzzing revealed a recursive locking violation in
usb-storage:

============================================
WARNING: possible recursive locking detected
5.18.0 STMicroelectronics#3 Not tainted
--------------------------------------------
kworker/1:3/1205 is trying to acquire lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230

but task is already holding lock:
ffff888018638db8 (&us_interface_key[i]){+.+.}-{3:3}, at:
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230

...

stack backtrace:
CPU: 1 PID: 1205 Comm: kworker/1:3 Not tainted 5.18.0 STMicroelectronics#3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
1.13.0-1ubuntu1.1 04/01/2014
Workqueue: usb_hub_wq hub_event
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_deadlock_bug kernel/locking/lockdep.c:2988 [inline]
check_deadlock kernel/locking/lockdep.c:3031 [inline]
validate_chain kernel/locking/lockdep.c:3816 [inline]
__lock_acquire.cold+0x152/0x3ca kernel/locking/lockdep.c:5053
lock_acquire kernel/locking/lockdep.c:5665 [inline]
lock_acquire+0x1ab/0x520 kernel/locking/lockdep.c:5630
__mutex_lock_common kernel/locking/mutex.c:603 [inline]
__mutex_lock+0x14f/0x1610 kernel/locking/mutex.c:747
usb_stor_pre_reset+0x35/0x40 drivers/usb/storage/usb.c:230
usb_reset_device+0x37d/0x9a0 drivers/usb/core/hub.c:6109
r871xu_dev_remove+0x21a/0x270 drivers/staging/rtl8712/usb_intf.c:622
usb_unbind_interface+0x1bd/0x890 drivers/usb/core/driver.c:458
device_remove drivers/base/dd.c:545 [inline]
device_remove+0x11f/0x170 drivers/base/dd.c:537
__device_release_driver drivers/base/dd.c:1222 [inline]
device_release_driver_internal+0x1a7/0x2f0 drivers/base/dd.c:1248
usb_driver_release_interface+0x102/0x180 drivers/usb/core/driver.c:627
usb_forced_unbind_intf+0x4d/0xa0 drivers/usb/core/driver.c:1118
usb_reset_device+0x39b/0x9a0 drivers/usb/core/hub.c:6114

This turned out not to be an error in usb-storage but rather a nested
device reset attempt.  That is, as the rtl8712 driver was being
unbound from a composite device in preparation for an unrelated USB
reset (that driver does not have pre_reset or post_reset callbacks),
its ->remove routine called usb_reset_device() -- thus nesting one
reset call within another.

Performing a reset as part of disconnect processing is a questionable
practice at best.  However, the bug report points out that the USB
core does not have any protection against nested resets.  Adding a
reset_in_progress flag and testing it will prevent such errors in the
future.

Link: https://lore.kernel.org/all/CAB7eexKUpvX-JNiLzhXBDWgfg2T9e9_0Tw4HQ6keN==voRbP0g@mail.gmail.com/
Cc: stable@vger.kernel.org
Reported-and-tested-by: Rondreis <linhaoguo86@gmail.com>
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Link: https://lore.kernel.org/r/YwkflDxvg0KWqyZK@rowland.harvard.edu
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
dponchalee pushed a commit to dponchalee/linux-st that referenced this pull request Feb 2, 2023
[ Upstream commit 84a5358 ]

The SRv6 layer allows defining HMAC data that can later be used to sign IPv6
Segment Routing Headers. This configuration is realised via netlink through
four attributes: SEG6_ATTR_HMACKEYID, SEG6_ATTR_SECRET, SEG6_ATTR_SECRETLEN and
SEG6_ATTR_ALGID. Because the SECRETLEN attribute is decoupled from the actual
length of the SECRET attribute, it is possible to provide invalid combinations
(e.g., secret = "", secretlen = 64). This case is not checked in the code and
with an appropriately crafted netlink message, an out-of-bounds read of up
to 64 bytes (max secret length) can occur past the skb end pointer and into
skb_shared_info:

Breakpoint 1, seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
208		memcpy(hinfo->secret, secret, slen);
(gdb) bt
 #0  seg6_genl_sethmac (skb=<optimized out>, info=<optimized out>) at net/ipv6/seg6.c:208
 STMicroelectronics#1  0xffffffff81e012e9 in genl_family_rcv_msg_doit (skb=skb@entry=0xffff88800b1f9f00, nlh=nlh@entry=0xffff88800b1b7600,
    extack=extack@entry=0xffffc90000ba7af0, ops=ops@entry=0xffffc90000ba7a80, hdrlen=4, net=0xffffffff84237580 <init_net>, family=<optimized out>,
    family=<optimized out>) at net/netlink/genetlink.c:731
 STMicroelectronics#2  0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00,
    family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775
 STMicroelectronics#3  genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792
 STMicroelectronics#4  0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>)
    at net/netlink/af_netlink.c:2501
 STMicroelectronics#5  0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803
 STMicroelectronics#6  0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000)
    at net/netlink/af_netlink.c:1319
 STMicroelectronics#7  netlink_unicast (ssk=ssk@entry=0xffff888010eec800, skb=skb@entry=0xffff88800b1f9f00, portid=portid@entry=0, nonblock=<optimized out>)
    at net/netlink/af_netlink.c:1345
 STMicroelectronics#8  0xffffffff81dff9a4 in netlink_sendmsg (sock=<optimized out>, msg=0xffffc90000ba7e48, len=<optimized out>) at net/netlink/af_netlink.c:1921
...
(gdb) p/x ((struct sk_buff *)0xffff88800b1f9f00)->head + ((struct sk_buff *)0xffff88800b1f9f00)->end
$1 = 0xffff88800b1b76c0
(gdb) p/x secret
$2 = 0xffff88800b1b76c0
(gdb) p slen
$3 = 64 '@'

The OOB data can then be read back from userspace by dumping HMAC state. This
commit fixes this by ensuring SECRETLEN cannot exceed the actual length of
SECRET.

Reported-by: Lucas Leong <wmliang.tw@gmail.com>
Tested: verified that EINVAL is correctly returned when secretlen > len(secret)
Fixes: 4f4853d ("ipv6: sr: implement API to control SR HMAC structure")
Signed-off-by: David Lebrun <dlebrun@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
dponchalee pushed a commit to dponchalee/linux-st that referenced this pull request Feb 2, 2023
[ Upstream commit dd80fb2 ]

"BUG: KASAN: stack-out-of-bounds in strncpy+0x30/0x68"

Linux-ATF interface is using 16 bytes of SMC payload. In case clock name is
longer than 15 bytes, string terminated NULL character will not be received
by Linux. Add explicit NULL character at last byte to fix issues when clock
name is longer.

This fixes below bug reported by KASAN:

 ==================================================================
 BUG: KASAN: stack-out-of-bounds in strncpy+0x30/0x68
 Read of size 1 at addr ffff0008c89a7410 by task swapper/0/1

 CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.4.0-00396-g81ef9e7-dirty STMicroelectronics#3
 Hardware name: Xilinx Versal vck190 Eval board revA (QSPI) (DT)
 Call trace:
  dump_backtrace+0x0/0x1e8
  show_stack+0x14/0x20
  dump_stack+0xd4/0x108
  print_address_description.isra.0+0xbc/0x37c
  __kasan_report+0x144/0x198
  kasan_report+0xc/0x18
  __asan_load1+0x5c/0x68
  strncpy+0x30/0x68
  zynqmp_clock_probe+0x238/0x7b8
  platform_drv_probe+0x6c/0xc8
  really_probe+0x14c/0x418
  driver_probe_device+0x74/0x130
  __device_attach_driver+0xc4/0xe8
  bus_for_each_drv+0xec/0x150
  __device_attach+0x160/0x1d8
  device_initial_probe+0x10/0x18
  bus_probe_device+0xe0/0xf0
  device_add+0x528/0x950
  of_device_add+0x5c/0x80
  of_platform_device_create_pdata+0x120/0x168
  of_platform_bus_create+0x244/0x4e0
  of_platform_populate+0x50/0xe8
  zynqmp_firmware_probe+0x370/0x3a8
  platform_drv_probe+0x6c/0xc8
  really_probe+0x14c/0x418
  driver_probe_device+0x74/0x130
  device_driver_attach+0x94/0xa0
  __driver_attach+0x70/0x108
  bus_for_each_dev+0xe4/0x158
  driver_attach+0x30/0x40
  bus_add_driver+0x21c/0x2b8
  driver_register+0xbc/0x1d0
  __platform_driver_register+0x7c/0x88
  zynqmp_firmware_driver_init+0x1c/0x24
  do_one_initcall+0xa4/0x234
  kernel_init_freeable+0x1b0/0x24c
  kernel_init+0x10/0x110
  ret_from_fork+0x10/0x18

 The buggy address belongs to the page:
 page:ffff0008f9be1c88 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0
 raw: 0008d00000000000 ffff0008f9be1c90 ffff0008f9be1c90 0000000000000000
 raw: 0000000000000000 0000000000000000 00000000ffffffff
 page dumped because: kasan: bad access detected

 addr ffff0008c89a7410 is located in stack of task swapper/0/1 at offset 112 in frame:
  zynqmp_clock_probe+0x0/0x7b8

 this frame has 3 objects:
  [32, 44) 'response'
  [64, 80) 'ret_payload'
  [96, 112) 'name'

 Memory state around the buggy address:
  ffff0008c89a7300: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff0008c89a7380: 00 00 00 00 f1 f1 f1 f1 00 04 f2 f2 00 00 f2 f2
 >ffff0008c89a7400: 00 00 f3 f3 00 00 00 00 00 00 00 00 00 00 00 00
                          ^
  ffff0008c89a7480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  ffff0008c89a7500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ==================================================================

Signed-off-by: Ian Nam <young.kwan.nam@xilinx.com>
Signed-off-by: Shubhrajyoti Datta <shubhrajyoti.datta@xilinx.com>
Link: https://lore.kernel.org/r/20220510070154.29528-3-shubhrajyoti.datta@xilinx.com
Acked-by: Michal Simek <michal.simek@amd.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
arnopo pushed a commit to arnopo/linux that referenced this pull request Aug 31, 2023
syzkaller found zero division error [0] in div_s64_rem() called from
get_cycle_time_elapsed(), where sched->cycle_time is the divisor.

We have tests in parse_taprio_schedule() so that cycle_time will never
be 0, and actually cycle_time is not 0 in get_cycle_time_elapsed().

The problem is that the types of divisor are different; cycle_time is
s64, but the argument of div_s64_rem() is s32.

syzkaller fed this input and 0x100000000 is cast to s32 to be 0.

  @TCA_TAPRIO_ATTR_SCHED_CYCLE_TIME={0xc, 0x8, 0x100000000}

We use s64 for cycle_time to cast it to ktime_t, so let's keep it and
set max for cycle_time.

While at it, we prevent overflow in setup_txtime() and add another
test in parse_taprio_schedule() to check if cycle_time overflows.

Also, we add a new tdc test case for this issue.

[0]:
divide error: 0000 [STMicroelectronics#1] PREEMPT SMP KASAN NOPTI
CPU: 1 PID: 103 Comm: kworker/1:3 Not tainted 6.5.0-rc1-00330-g60cc1f7d0605 STMicroelectronics#3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
Workqueue: ipv6_addrconf addrconf_dad_work
RIP: 0010:div_s64_rem include/linux/math64.h:42 [inline]
RIP: 0010:get_cycle_time_elapsed net/sched/sch_taprio.c:223 [inline]
RIP: 0010:find_entry_to_transmit+0x252/0x7e0 net/sched/sch_taprio.c:344
Code: 3c 02 00 0f 85 5e 05 00 00 48 8b 4c 24 08 4d 8b bd 40 01 00 00 48 8b 7c 24 48 48 89 c8 4c 29 f8 48 63 f7 48 99 48 89 74 24 70 <48> f7 fe 48 29 d1 48 8d 04 0f 49 89 cc 48 89 44 24 20 49 8d 85 10
RSP: 0018:ffffc90000acf260 EFLAGS: 00010206
RAX: 177450e0347560cf RBX: 0000000000000000 RCX: 177450e0347560cf
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000100000000
RBP: 0000000000000056 R08: 0000000000000000 R09: ffffed10020a0934
R10: ffff8880105049a7 R11: ffff88806cf3a520 R12: ffff888010504800
R13: ffff88800c00d800 R14: ffff8880105049a0 R15: 0000000000000000
FS:  0000000000000000(0000) GS:ffff88806cf00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f0edf84f0e8 CR3: 000000000d73c002 CR4: 0000000000770ee0
PKRU: 55555554
Call Trace:
 <TASK>
 get_packet_txtime net/sched/sch_taprio.c:508 [inline]
 taprio_enqueue_one+0x900/0xff0 net/sched/sch_taprio.c:577
 taprio_enqueue+0x378/0xae0 net/sched/sch_taprio.c:658
 dev_qdisc_enqueue+0x46/0x170 net/core/dev.c:3732
 __dev_xmit_skb net/core/dev.c:3821 [inline]
 __dev_queue_xmit+0x1b2f/0x3000 net/core/dev.c:4169
 dev_queue_xmit include/linux/netdevice.h:3088 [inline]
 neigh_resolve_output net/core/neighbour.c:1552 [inline]
 neigh_resolve_output+0x4a7/0x780 net/core/neighbour.c:1532
 neigh_output include/net/neighbour.h:544 [inline]
 ip6_finish_output2+0x924/0x17d0 net/ipv6/ip6_output.c:135
 __ip6_finish_output+0x620/0xaa0 net/ipv6/ip6_output.c:196
 ip6_finish_output net/ipv6/ip6_output.c:207 [inline]
 NF_HOOK_COND include/linux/netfilter.h:292 [inline]
 ip6_output+0x206/0x410 net/ipv6/ip6_output.c:228
 dst_output include/net/dst.h:458 [inline]
 NF_HOOK.constprop.0+0xea/0x260 include/linux/netfilter.h:303
 ndisc_send_skb+0x872/0xe80 net/ipv6/ndisc.c:508
 ndisc_send_ns+0xb5/0x130 net/ipv6/ndisc.c:666
 addrconf_dad_work+0xc14/0x13f0 net/ipv6/addrconf.c:4175
 process_one_work+0x92c/0x13a0 kernel/workqueue.c:2597
 worker_thread+0x60f/0x1240 kernel/workqueue.c:2748
 kthread+0x2fe/0x3f0 kernel/kthread.c:389
 ret_from_fork+0x2c/0x50 arch/x86/entry/entry_64.S:308
 </TASK>
Modules linked in:

Fixes: 4cfd577 ("taprio: Add support for txtime-assist mode")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Co-developed-by: Eric Dumazet <edumazet@google.com>
Co-developed-by: Pedro Tammela <pctammela@mojatatu.com>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
arnopo pushed a commit to arnopo/linux that referenced this pull request Aug 31, 2023
Ido Schimmel says:

====================
nexthop: Nexthop dump fixes

Patches STMicroelectronics#1 and STMicroelectronics#3 fix two problems related to nexthops and nexthop
buckets dump, respectively. Patch STMicroelectronics#2 is a preparation for the third
patch.

The pattern described in these patches of splitting the NLMSG_DONE to a
separate response is prevalent in other rtnetlink dump callbacks. I
don't know if it's because I'm missing something or if this was done
intentionally to ensure the message is delivered to user space. After
commit 0642840 ("af_netlink: ensure that NLMSG_DONE never fails in
dumps") this is no longer necessary and I can improve these dump
callbacks assuming this analysis is correct.

No regressions in existing tests:

 # ./fib_nexthops.sh
 [...]
 Tests passed: 230
 Tests failed:   0
====================

Link: https://lore.kernel.org/r/20230808075233.3337922-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
arnopo pushed a commit to arnopo/linux that referenced this pull request Aug 31, 2023
qxl_mode_dumb_create() dereferences the qobj returned by
qxl_gem_object_create_with_handle(), but the handle is the only one
holding a reference to it.

A potential attacker could guess the returned handle value and closes it
between the return of qxl_gem_object_create_with_handle() and the qobj
usage, triggering a use-after-free scenario.

Reproducer:

int dri_fd =-1;
struct drm_mode_create_dumb arg = {0};

void gem_close(int handle);

void* trigger(void* ptr)
{
	int ret;
	arg.width = arg.height = 0x20;
	arg.bpp = 32;
	ret = ioctl(dri_fd, DRM_IOCTL_MODE_CREATE_DUMB, &arg);
	if(ret)
	{
		perror("[*] DRM_IOCTL_MODE_CREATE_DUMB Failed");
		exit(-1);
	}
	gem_close(arg.handle);
	while(1) {
		struct drm_mode_create_dumb args = {0};
		args.width = args.height = 0x20;
		args.bpp = 32;
		ret = ioctl(dri_fd, DRM_IOCTL_MODE_CREATE_DUMB, &args);
		if (ret) {
			perror("[*] DRM_IOCTL_MODE_CREATE_DUMB Failed");
			exit(-1);
		}

		printf("[*] DRM_IOCTL_MODE_CREATE_DUMB created, %d\n", args.handle);
		gem_close(args.handle);
	}
	return NULL;
}

void gem_close(int handle)
{
	struct drm_gem_close args;
	args.handle = handle;
	int ret = ioctl(dri_fd, DRM_IOCTL_GEM_CLOSE, &args); // gem close handle
	if (!ret)
		printf("gem close handle %d\n", args.handle);
}

int main(void)
{
	dri_fd= open("/dev/dri/card0", O_RDWR);
	printf("fd:%d\n", dri_fd);

	if(dri_fd == -1)
		return -1;

	pthread_t tid1;

	if(pthread_create(&tid1,NULL,trigger,NULL)){
		perror("[*] thread_create tid1\n");
		return -1;
	}
	while (1)
	{
		gem_close(arg.handle);
	}
	return 0;
}

This is a KASAN report:

==================================================================
BUG: KASAN: slab-use-after-free in qxl_mode_dumb_create+0x3c2/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:69
Write of size 1 at addr ffff88801136c240 by task poc/515

CPU: 1 PID: 515 Comm: poc Not tainted 6.3.0 STMicroelectronics#3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.16.0-debian-1.16.0-4 04/01/2014
Call Trace:
<TASK>
__dump_stack linux/lib/dump_stack.c:88
dump_stack_lvl+0x48/0x70 linux/lib/dump_stack.c:106
print_address_description linux/mm/kasan/report.c:319
print_report+0xd2/0x660 linux/mm/kasan/report.c:430
kasan_report+0xd2/0x110 linux/mm/kasan/report.c:536
__asan_report_store1_noabort+0x17/0x30 linux/mm/kasan/report_generic.c:383
qxl_mode_dumb_create+0x3c2/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:69
drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96
drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102
drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788
drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891
vfs_ioctl linux/fs/ioctl.c:51
__do_sys_ioctl linux/fs/ioctl.c:870
__se_sys_ioctl linux/fs/ioctl.c:856
__x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856
do_syscall_x64 linux/arch/x86/entry/common.c:50
do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120
RIP: 0033:0x7ff5004ff5f7
Code: 00 00 00 48 8b 05 99 c8 0d 00 64 c7 00 26 00 00 00 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 b8 10 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 8b 0d 69 c8 0d 00 f7 d8 64 89 01 48

RSP: 002b:00007ff500408ea8 EFLAGS: 00000286 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007ff5004ff5f7
RDX: 00007ff500408ec0 RSI: 00000000c02064b2 RDI: 0000000000000003
RBP: 00007ff500408ef0 R08: 0000000000000000 R09: 000000000000002a
R10: 0000000000000000 R11: 0000000000000286 R12: 00007fff1c6cdafe
R13: 00007fff1c6cdaff R14: 00007ff500408fc0 R15: 0000000000802000
</TASK>

Allocated by task 515:
kasan_save_stack+0x38/0x70 linux/mm/kasan/common.c:45
kasan_set_track+0x25/0x40 linux/mm/kasan/common.c:52
kasan_save_alloc_info+0x1e/0x40 linux/mm/kasan/generic.c:510
____kasan_kmalloc linux/mm/kasan/common.c:374
__kasan_kmalloc+0xc3/0xd0 linux/mm/kasan/common.c:383
kasan_kmalloc linux/./include/linux/kasan.h:196
kmalloc_trace+0x48/0xc0 linux/mm/slab_common.c:1066
kmalloc linux/./include/linux/slab.h:580
kzalloc linux/./include/linux/slab.h:720
qxl_bo_create+0x11a/0x610 linux/drivers/gpu/drm/qxl/qxl_object.c:124
qxl_gem_object_create+0xd9/0x360 linux/drivers/gpu/drm/qxl/qxl_gem.c:58
qxl_gem_object_create_with_handle+0xa1/0x180 linux/drivers/gpu/drm/qxl/qxl_gem.c:89
qxl_mode_dumb_create+0x1cd/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:63
drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96
drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102
drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788
drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891
vfs_ioctl linux/fs/ioctl.c:51
__do_sys_ioctl linux/fs/ioctl.c:870
__se_sys_ioctl linux/fs/ioctl.c:856
__x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856
do_syscall_x64 linux/arch/x86/entry/common.c:50
do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120

Freed by task 515:
kasan_save_stack+0x38/0x70 linux/mm/kasan/common.c:45
kasan_set_track+0x25/0x40 linux/mm/kasan/common.c:52
kasan_save_free_info+0x2e/0x60 linux/mm/kasan/generic.c:521
____kasan_slab_free linux/mm/kasan/common.c:236
____kasan_slab_free+0x180/0x1f0 linux/mm/kasan/common.c:200
__kasan_slab_free+0x12/0x30 linux/mm/kasan/common.c:244
kasan_slab_free linux/./include/linux/kasan.h:162
slab_free_hook linux/mm/slub.c:1781
slab_free_freelist_hook+0xd2/0x1a0 linux/mm/slub.c:1807
slab_free linux/mm/slub.c:3787
__kmem_cache_free+0x196/0x2d0 linux/mm/slub.c:3800
kfree+0x78/0x120 linux/mm/slab_common.c:1019
qxl_ttm_bo_destroy+0x140/0x1a0 linux/drivers/gpu/drm/qxl/qxl_object.c:49
ttm_bo_release+0x678/0xa30 linux/drivers/gpu/drm/ttm/ttm_bo.c:381
kref_put linux/./include/linux/kref.h:65
ttm_bo_put+0x50/0x80 linux/drivers/gpu/drm/ttm/ttm_bo.c:393
qxl_gem_object_free+0x3e/0x60 linux/drivers/gpu/drm/qxl/qxl_gem.c:42
drm_gem_object_free+0x5c/0x90 linux/drivers/gpu/drm/drm_gem.c:974
kref_put linux/./include/linux/kref.h:65
__drm_gem_object_put linux/./include/drm/drm_gem.h:431
drm_gem_object_put linux/./include/drm/drm_gem.h:444
qxl_gem_object_create_with_handle+0x151/0x180 linux/drivers/gpu/drm/qxl/qxl_gem.c:100
qxl_mode_dumb_create+0x1cd/0x400 linux/drivers/gpu/drm/qxl/qxl_dumb.c:63
drm_mode_create_dumb linux/drivers/gpu/drm/drm_dumb_buffers.c:96
drm_mode_create_dumb_ioctl+0x1f5/0x2d0 linux/drivers/gpu/drm/drm_dumb_buffers.c:102
drm_ioctl_kernel+0x21d/0x430 linux/drivers/gpu/drm/drm_ioctl.c:788
drm_ioctl+0x56f/0xcc0 linux/drivers/gpu/drm/drm_ioctl.c:891
vfs_ioctl linux/fs/ioctl.c:51
__do_sys_ioctl linux/fs/ioctl.c:870
__se_sys_ioctl linux/fs/ioctl.c:856
__x64_sys_ioctl+0x13d/0x1c0 linux/fs/ioctl.c:856
do_syscall_x64 linux/arch/x86/entry/common.c:50
do_syscall_64+0x5b/0x90 linux/arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x72/0xdc linux/arch/x86/entry/entry_64.S:120

The buggy address belongs to the object at ffff88801136c000
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 576 bytes inside of
freed 1024-byte region [ffff88801136c000, ffff88801136c400)

The buggy address belongs to the physical page:
page:0000000089fc329b refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11368
head:0000000089fc329b order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff)
raw: 000fffffc0010200 ffff888007841dc0 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
ffff88801136c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801136c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88801136c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801136c280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801136c300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Disabling lock debugging due to kernel taint

Instead of returning a weak reference to the qxl_bo object, return the
created drm_gem_object and let the caller decrement the reference count
when it no longer needs it. As a convenience, if the caller is not
interested in the gobj object, it can pass NULL to the parameter and the
reference counting is descremented internally.

The bug and the reproducer were originally found by the Zero Day Initiative project (ZDI-CAN-20940).

Link: https://www.zerodayinitiative.com/
Signed-off-by: Wander Lairson Costa <wander@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230814165119.90847-1-wander@redhat.com
arnopo pushed a commit to arnopo/linux that referenced this pull request Aug 31, 2023
… via GUP-fast

In contrast to most other GUP code, GUP-fast common page table walking
code like gup_pte_range() also handles hugetlb pages.  But in contrast to
other hugetlb page table walking code, it does not look at the hugetlb PTE
abstraction whereby we have only a single logical hugetlb PTE per hugetlb
page, even when using multiple cont-PTEs underneath -- which is for
example what huge_ptep_get() abstracts.

So when we have a hugetlb page that is mapped via cont-PTEs, GUP-fast
might stumble over a PTE that does not map the head page of a hugetlb page
-- not the first "head" PTE of such a cont mapping.

Logically, the whole hugetlb page is mapped (entire_mapcount == 1), but we
might end up calling gup_must_unshare() with a tail page of a hugetlb
page.

We only maintain a single PageAnonExclusive flag per hugetlb page (as
hugetlb pages cannot get partially COW-shared), stored for the head page. 
That flag is clear for all tail pages.

So when gup_must_unshare() ends up calling PageAnonExclusive() with a tail
page of a hugetlb page:

1) With CONFIG_DEBUG_VM_PGFLAGS

Stumbles over the:

	VM_BUG_ON_PGFLAGS(PageHuge(page) && !PageHead(page), page);

For example, when executing the COW selftests with 64k hugetlb pages on
arm64:

  [   61.082187] page:00000000829819ff refcount:3 mapcount:1 mapping:0000000000000000 index:0x1 pfn:0x11ee11
  [   61.082842] head:0000000080f79bf7 order:4 entire_mapcount:1 nr_pages_mapped:0 pincount:2
  [   61.083384] anon flags: 0x17ffff80003000e(referenced|uptodate|dirty|head|mappedtodisk|node=0|zone=2|lastcpupid=0xfffff)
  [   61.084101] page_type: 0xffffffff()
  [   61.084332] raw: 017ffff800000000 fffffc00037b8401 0000000000000402 0000000200000000
  [   61.084840] raw: 0000000000000010 0000000000000000 00000000ffffffff 0000000000000000
  [   61.085359] head: 017ffff80003000e ffffd9e95b09b788 ffffd9e95b09b788 ffff0007ff63cf71
  [   61.085885] head: 0000000000000000 0000000000000002 00000003ffffffff 0000000000000000
  [   61.086415] page dumped because: VM_BUG_ON_PAGE(PageHuge(page) && !PageHead(page))
  [   61.086914] ------------[ cut here ]------------
  [   61.087220] kernel BUG at include/linux/page-flags.h:990!
  [   61.087591] Internal error: Oops - BUG: 00000000f2000800 [STMicroelectronics#1] SMP
  [   61.087999] Modules linked in: ...
  [   61.089404] CPU: 0 PID: 4612 Comm: cow Kdump: loaded Not tainted 6.5.0-rc4+ STMicroelectronics#3
  [   61.089917] Hardware name: QEMU KVM Virtual Machine, BIOS 0.0.0 02/06/2015
  [   61.090409] pstate: 604000c5 (nZCv daIF +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
  [   61.090897] pc : gup_must_unshare.part.0+0x64/0x98
  [   61.091242] lr : gup_must_unshare.part.0+0x64/0x98
  [   61.091592] sp : ffff8000825eb940
  [   61.091826] x29: ffff8000825eb940 x28: 0000000000000000 x27: fffffc00037b8440
  [   61.092329] x26: 0400000000000001 x25: 0000000000080101 x24: 0000000000080000
  [   61.092835] x23: 0000000000080100 x22: ffff0000cffb9588 x21: ffff0000c8ec6b58
  [   61.093341] x20: 0000ffffad6b1000 x19: fffffc00037b8440 x18: ffffffffffffffff
  [   61.093850] x17: 2864616548656761 x16: 5021202626202965 x15: 6761702865677548
  [   61.094358] x14: 6567615028454741 x13: 2929656761702864 x12: 6165486567615021
  [   61.094858] x11: 00000000ffff7fff x10: 00000000ffff7fff x9 : ffffd9e958b7a1c0
  [   61.095359] x8 : 00000000000bffe8 x7 : c0000000ffff7fff x6 : 00000000002bffa8
  [   61.095873] x5 : ffff0008bb19e708 x4 : 0000000000000000 x3 : 0000000000000000
  [   61.096380] x2 : 0000000000000000 x1 : ffff0000cf6636c0 x0 : 0000000000000046
  [   61.096894] Call trace:
  [   61.097080]  gup_must_unshare.part.0+0x64/0x98
  [   61.097392]  gup_pte_range+0x3a8/0x3f0
  [   61.097662]  gup_pgd_range+0x1ec/0x280
  [   61.097942]  lockless_pages_from_mm+0x64/0x1a0
  [   61.098258]  internal_get_user_pages_fast+0xe4/0x1d0
  [   61.098612]  pin_user_pages_fast+0x58/0x78
  [   61.098917]  pin_longterm_test_start+0xf4/0x2b8
  [   61.099243]  gup_test_ioctl+0x170/0x3b0
  [   61.099528]  __arm64_sys_ioctl+0xa8/0xf0
  [   61.099822]  invoke_syscall.constprop.0+0x7c/0xd0
  [   61.100160]  el0_svc_common.constprop.0+0xe8/0x100
  [   61.100500]  do_el0_svc+0x38/0xa0
  [   61.100736]  el0_svc+0x3c/0x198
  [   61.100971]  el0t_64_sync_handler+0x134/0x150
  [   61.101280]  el0t_64_sync+0x17c/0x180
  [   61.101543] Code: aa1303e0 f00074c1 912b0021 97fffeb2 (d4210000)

2) Without CONFIG_DEBUG_VM_PGFLAGS

Always detects "not exclusive" for passed tail pages and refuses to PIN
the tail pages R/O, as gup_must_unshare() == true.  GUP-fast will fallback
to ordinary GUP.  As ordinary GUP properly considers the logical hugetlb
PTE abstraction in hugetlb_follow_page_mask(), pinning the page will
succeed when looking at the PageAnonExclusive on the head page only.

So the only real effect of this is that with cont-PTE hugetlb pages, we'll
always fallback from GUP-fast to ordinary GUP when not working on the head
page, which ends up checking the head page and do the right thing.

Consequently, the cow selftests pass with cont-PTE hugetlb pages as well
without CONFIG_DEBUG_VM_PGFLAGS.

Note that this only applies to anon hugetlb pages that are mapped using
cont-PTEs: for example 64k hugetlb pages on a 4k arm64 kernel.

... and only when R/O-pinning (FOLL_PIN) such pages that are mapped into
the page table R/O using GUP-fast.

On production kernels (and even most debug kernels, that don't set
CONFIG_DEBUG_VM_PGFLAGS) this patch should theoretically not be required
to be backported.  But of course, it does not hurt.

Link: https://lkml.kernel.org/r/20230805101256.87306-1-david@redhat.com
Fixes: a7f2266 ("mm/gup: trigger FAULT_FLAG_UNSHARE when R/O-pinning a possibly shared anonymous page")
Signed-off-by: David Hildenbrand <david@redhat.com>
Reported-by: Ryan Roberts <ryan.roberts@arm.com>
Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Tested-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
devik2 pushed a commit to devik2/st_linux that referenced this pull request Oct 31, 2023
[ Upstream commit aa880ad ]

When we increase hardware queue count, blk_mq_update_queue_map will
reset the mapping between cpu and hardware queue base on the hardware
queue count(set->nr_hw_queues). The mapping cannot be reset if it
encounters error in blk_mq_realloc_hw_ctxs, but the fallback flow will
continue using it, then blk_mq_map_swqueue will touch a invalid memory,
because the mapping points to a wrong hctx.

blktest block/030:

null_blk: module loaded
Increasing nr_hw_queues to 8 fails, fallback to 1
==================================================================
BUG: KASAN: null-ptr-deref in blk_mq_map_swqueue+0x2f2/0x830
Read of size 8 at addr 0000000000000128 by task nproc/8541

CPU: 5 PID: 8541 Comm: nproc Not tainted 5.7.0-rc4-dbg+ STMicroelectronics#3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.13.0-0-gf21b5a4-rebuilt.opensuse.org 04/01/2014
Call Trace:
dump_stack+0xa5/0xe6
__kasan_report.cold+0x65/0xbb
kasan_report+0x45/0x60
check_memory_region+0x15e/0x1c0
__kasan_check_read+0x15/0x20
blk_mq_map_swqueue+0x2f2/0x830
__blk_mq_update_nr_hw_queues+0x3df/0x690
blk_mq_update_nr_hw_queues+0x32/0x50
nullb_device_submit_queues_store+0xde/0x160 [null_blk]
configfs_write_file+0x1c4/0x250 [configfs]
__vfs_write+0x4c/0x90
vfs_write+0x14b/0x2d0
ksys_write+0xdd/0x180
__x64_sys_write+0x47/0x50
do_syscall_64+0x6f/0x310
entry_SYSCALL_64_after_hwframe+0x49/0xb3

Signed-off-by: Weiping Zhang <zhangweiping@didiglobal.com>
Tested-by: Bart van Assche <bvanassche@acm.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Sasha Levin <sashal@kernel.org>
devik2 pushed a commit to devik2/st_linux that referenced this pull request Oct 31, 2023
[ Upstream commit 6dcde60 ]

Dave Airlie reported the following lockdep complaint:

>  ======================================================
>  WARNING: possible circular locking dependency detected
>  5.7.0-0.rc5.20200515git1ae7efb38854.1.fc33.x86_64 STMicroelectronics#1 Not tainted
>  ------------------------------------------------------
>  kswapd0/159 is trying to acquire lock:
>  ffff9b38d01a4470 (&xfs_nondir_ilock_class){++++}-{3:3},
>  at: xfs_ilock+0xde/0x2c0 [xfs]
>
>  but task is already holding lock:
>  ffffffffbbb8bd00 (fs_reclaim){+.+.}-{0:0}, at:
>  __fs_reclaim_acquire+0x5/0x30
>
>  which lock already depends on the new lock.
>
>
>  the existing dependency chain (in reverse order) is:
>
>  -> STMicroelectronics#1 (fs_reclaim){+.+.}-{0:0}:
>         fs_reclaim_acquire+0x34/0x40
>         __kmalloc+0x4f/0x270
>         kmem_alloc+0x93/0x1d0 [xfs]
>         kmem_alloc_large+0x4c/0x130 [xfs]
>         xfs_attr_copy_value+0x74/0xa0 [xfs]
>         xfs_attr_get+0x9d/0xc0 [xfs]
>         xfs_get_acl+0xb6/0x200 [xfs]
>         get_acl+0x81/0x160
>         posix_acl_xattr_get+0x3f/0xd0
>         vfs_getxattr+0x148/0x170
>         getxattr+0xa7/0x240
>         path_getxattr+0x52/0x80
>         do_syscall_64+0x5c/0xa0
>         entry_SYSCALL_64_after_hwframe+0x49/0xb3
>
>  -> #0 (&xfs_nondir_ilock_class){++++}-{3:3}:
>         __lock_acquire+0x1257/0x20d0
>         lock_acquire+0xb0/0x310
>         down_write_nested+0x49/0x120
>         xfs_ilock+0xde/0x2c0 [xfs]
>         xfs_reclaim_inode+0x3f/0x400 [xfs]
>         xfs_reclaim_inodes_ag+0x20b/0x410 [xfs]
>         xfs_reclaim_inodes_nr+0x31/0x40 [xfs]
>         super_cache_scan+0x190/0x1e0
>         do_shrink_slab+0x184/0x420
>         shrink_slab+0x182/0x290
>         shrink_node+0x174/0x680
>         balance_pgdat+0x2d0/0x5f0
>         kswapd+0x21f/0x510
>         kthread+0x131/0x150
>         ret_from_fork+0x3a/0x50
>
>  other info that might help us debug this:
>
>   Possible unsafe locking scenario:
>
>         CPU0                    CPU1
>         ----                    ----
>    lock(fs_reclaim);
>                                 lock(&xfs_nondir_ilock_class);
>                                 lock(fs_reclaim);
>    lock(&xfs_nondir_ilock_class);
>
>   *** DEADLOCK ***
>
>  4 locks held by kswapd0/159:
>   #0: ffffffffbbb8bd00 (fs_reclaim){+.+.}-{0:0}, at:
>  __fs_reclaim_acquire+0x5/0x30
>   STMicroelectronics#1: ffffffffbbb7cef8 (shrinker_rwsem){++++}-{3:3}, at:
>  shrink_slab+0x115/0x290
>   STMicroelectronics#2: ffff9b39f07a50e8
>  (&type->s_umount_key#56){++++}-{3:3}, at: super_cache_scan+0x38/0x1e0
>   STMicroelectronics#3: ffff9b39f077f258
>  (&pag->pag_ici_reclaim_lock){+.+.}-{3:3}, at:
>  xfs_reclaim_inodes_ag+0x82/0x410 [xfs]

This is a known false positive because inodes cannot simultaneously be
getting reclaimed and the target of a getxattr operation, but lockdep
doesn't know that.  We can (selectively) shut up lockdep until either
it gets smarter or we change inode reclaim not to require the ILOCK by
applying a stupid GFP_NOLOCKDEP bandaid.

Reported-by: Dave Airlie <airlied@gmail.com>
Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Tested-by: Dave Airlie <airlied@gmail.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
devik2 pushed a commit to devik2/st_linux that referenced this pull request Oct 31, 2023
[ Upstream commit f6766ff ]

We need to check mddev->del_work before flush workqueu since the purpose
of flush is to ensure the previous md is disappeared. Otherwise the similar
deadlock appeared if LOCKDEP is enabled, it is due to md_open holds the
bdev->bd_mutex before flush workqueue.

kernel: [  154.522645] ======================================================
kernel: [  154.522647] WARNING: possible circular locking dependency detected
kernel: [  154.522650] 5.6.0-rc7-lp151.27-default torvalds#25 Tainted: G           O
kernel: [  154.522651] ------------------------------------------------------
kernel: [  154.522653] mdadm/2482 is trying to acquire lock:
kernel: [  154.522655] ffff888078529128 ((wq_completion)md_misc){+.+.}, at: flush_workqueue+0x84/0x4b0
kernel: [  154.522673]
kernel: [  154.522673] but task is already holding lock:
kernel: [  154.522675] ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522691]
kernel: [  154.522691] which lock already depends on the new lock.
kernel: [  154.522691]
kernel: [  154.522694]
kernel: [  154.522694] the existing dependency chain (in reverse order) is:
kernel: [  154.522696]
kernel: [  154.522696] -> STMicroelectronics#4 (&bdev->bd_mutex){+.+.}:
kernel: [  154.522704]        __mutex_lock+0x87/0x950
kernel: [  154.522706]        __blkdev_get+0x79/0x590
kernel: [  154.522708]        blkdev_get+0x65/0x140
kernel: [  154.522709]        blkdev_get_by_dev+0x2f/0x40
kernel: [  154.522716]        lock_rdev+0x3d/0x90 [md_mod]
kernel: [  154.522719]        md_import_device+0xd6/0x1b0 [md_mod]
kernel: [  154.522723]        new_dev_store+0x15e/0x210 [md_mod]
kernel: [  154.522728]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522732]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522735]        vfs_write+0xad/0x1a0
kernel: [  154.522737]        ksys_write+0xa4/0xe0
kernel: [  154.522745]        do_syscall_64+0x64/0x2b0
kernel: [  154.522748]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522749]
kernel: [  154.522749] -> STMicroelectronics#3 (&mddev->reconfig_mutex){+.+.}:
kernel: [  154.522752]        __mutex_lock+0x87/0x950
kernel: [  154.522756]        new_dev_store+0xc9/0x210 [md_mod]
kernel: [  154.522759]        md_attr_store+0x7a/0xc0 [md_mod]
kernel: [  154.522761]        kernfs_fop_write+0x117/0x1b0
kernel: [  154.522763]        vfs_write+0xad/0x1a0
kernel: [  154.522765]        ksys_write+0xa4/0xe0
kernel: [  154.522767]        do_syscall_64+0x64/0x2b0
kernel: [  154.522769]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522770]
kernel: [  154.522770] -> STMicroelectronics#2 (kn->count#253){++++}:
kernel: [  154.522775]        __kernfs_remove+0x253/0x2c0
kernel: [  154.522778]        kernfs_remove+0x1f/0x30
kernel: [  154.522780]        kobject_del+0x28/0x60
kernel: [  154.522783]        mddev_delayed_delete+0x24/0x30 [md_mod]
kernel: [  154.522786]        process_one_work+0x2a7/0x5f0
kernel: [  154.522788]        worker_thread+0x2d/0x3d0
kernel: [  154.522793]        kthread+0x117/0x130
kernel: [  154.522795]        ret_from_fork+0x3a/0x50
kernel: [  154.522796]
kernel: [  154.522796] -> STMicroelectronics#1 ((work_completion)(&mddev->del_work)){+.+.}:
kernel: [  154.522800]        process_one_work+0x27e/0x5f0
kernel: [  154.522802]        worker_thread+0x2d/0x3d0
kernel: [  154.522804]        kthread+0x117/0x130
kernel: [  154.522806]        ret_from_fork+0x3a/0x50
kernel: [  154.522807]
kernel: [  154.522807] -> #0 ((wq_completion)md_misc){+.+.}:
kernel: [  154.522813]        __lock_acquire+0x1392/0x1690
kernel: [  154.522816]        lock_acquire+0xb4/0x1a0
kernel: [  154.522818]        flush_workqueue+0xab/0x4b0
kernel: [  154.522821]        md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522823]        __blkdev_get+0xea/0x590
kernel: [  154.522825]        blkdev_get+0x65/0x140
kernel: [  154.522828]        do_dentry_open+0x1d1/0x380
kernel: [  154.522831]        path_openat+0x567/0xcc0
kernel: [  154.522834]        do_filp_open+0x9b/0x110
kernel: [  154.522836]        do_sys_openat2+0x201/0x2a0
kernel: [  154.522838]        do_sys_open+0x57/0x80
kernel: [  154.522840]        do_syscall_64+0x64/0x2b0
kernel: [  154.522842]        entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522844]
kernel: [  154.522844] other info that might help us debug this:
kernel: [  154.522844]
kernel: [  154.522846] Chain exists of:
kernel: [  154.522846]   (wq_completion)md_misc --> &mddev->reconfig_mutex --> &bdev->bd_mutex
kernel: [  154.522846]
kernel: [  154.522850]  Possible unsafe locking scenario:
kernel: [  154.522850]
kernel: [  154.522852]        CPU0                    CPU1
kernel: [  154.522853]        ----                    ----
kernel: [  154.522854]   lock(&bdev->bd_mutex);
kernel: [  154.522856]                                lock(&mddev->reconfig_mutex);
kernel: [  154.522858]                                lock(&bdev->bd_mutex);
kernel: [  154.522860]   lock((wq_completion)md_misc);
kernel: [  154.522861]
kernel: [  154.522861]  *** DEADLOCK ***
kernel: [  154.522861]
kernel: [  154.522864] 1 lock held by mdadm/2482:
kernel: [  154.522865]  #0: ffff88804efa9338 (&bdev->bd_mutex){+.+.}, at: __blkdev_get+0x79/0x590
kernel: [  154.522868]
kernel: [  154.522868] stack backtrace:
kernel: [  154.522873] CPU: 1 PID: 2482 Comm: mdadm Tainted: G           O      5.6.0-rc7-lp151.27-default torvalds#25
kernel: [  154.522875] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 04/01/2014
kernel: [  154.522878] Call Trace:
kernel: [  154.522881]  dump_stack+0x8f/0xcb
kernel: [  154.522884]  check_noncircular+0x194/0x1b0
kernel: [  154.522888]  ? __lock_acquire+0x1392/0x1690
kernel: [  154.522890]  __lock_acquire+0x1392/0x1690
kernel: [  154.522893]  lock_acquire+0xb4/0x1a0
kernel: [  154.522895]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522898]  flush_workqueue+0xab/0x4b0
kernel: [  154.522900]  ? flush_workqueue+0x84/0x4b0
kernel: [  154.522905]  ? md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522908]  md_open+0xb6/0xc0 [md_mod]
kernel: [  154.522910]  __blkdev_get+0xea/0x590
kernel: [  154.522912]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522914]  blkdev_get+0x65/0x140
kernel: [  154.522916]  ? bd_acquire+0xc0/0xc0
kernel: [  154.522918]  do_dentry_open+0x1d1/0x380
kernel: [  154.522921]  path_openat+0x567/0xcc0
kernel: [  154.522923]  ? __lock_acquire+0x380/0x1690
kernel: [  154.522926]  do_filp_open+0x9b/0x110
kernel: [  154.522929]  ? __alloc_fd+0xe5/0x1f0
kernel: [  154.522935]  ? kmem_cache_alloc+0x28c/0x630
kernel: [  154.522939]  ? do_sys_openat2+0x201/0x2a0
kernel: [  154.522941]  do_sys_openat2+0x201/0x2a0
kernel: [  154.522944]  do_sys_open+0x57/0x80
kernel: [  154.522946]  do_syscall_64+0x64/0x2b0
kernel: [  154.522948]  entry_SYSCALL_64_after_hwframe+0x49/0xbe
kernel: [  154.522951] RIP: 0033:0x7f98d279d9ae

And md_alloc also flushed the same workqueue, but the thing is different
here. Because all the paths call md_alloc don't hold bdev->bd_mutex, and
the flush is necessary to avoid race condition, so leave it as it is.

Signed-off-by: Guoqing Jiang <guoqing.jiang@cloud.ionos.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
mingzhangqun pushed a commit to mingzhangqun/st-linux that referenced this pull request Mar 23, 2024
[ Upstream commit 91d6a46 ]

gpi_ch_init() doesn't lock the ctrl_lock mutex, so there is no need to
unlock it too. Instead the mutex is handled by the function
gpi_alloc_chan_resources(), which properly locks and unlocks the mutex.

=====================================
WARNING: bad unlock balance detected!
6.3.0-rc5-00253-g99792582ded1-dirty STMicroelectronics#15 Not tainted
-------------------------------------
kworker/u16:0/9 is trying to release lock (&gpii->ctrl_lock) at:
[<ffffb99d04e1284c>] gpi_alloc_chan_resources+0x108/0x5bc
but there are no more locks to release!

other info that might help us debug this:
6 locks held by kworker/u16:0/9:
 #0: ffff575740010938 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x220/0x594
 STMicroelectronics#1: ffff80000809bdd0 (deferred_probe_work){+.+.}-{0:0}, at: process_one_work+0x220/0x594
 STMicroelectronics#2: ffff575740f2a0f8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x38/0x188
 STMicroelectronics#3: ffff57574b5570f8 (&dev->mutex){....}-{3:3}, at: __device_attach+0x38/0x188
 STMicroelectronics#4: ffffb99d06a2f180 (of_dma_lock){+.+.}-{3:3}, at: of_dma_request_slave_channel+0x138/0x280
 STMicroelectronics#5: ffffb99d06a2ee20 (dma_list_mutex){+.+.}-{3:3}, at: dma_get_slave_channel+0x28/0x10c

stack backtrace:
CPU: 7 PID: 9 Comm: kworker/u16:0 Not tainted 6.3.0-rc5-00253-g99792582ded1-dirty STMicroelectronics#15
Hardware name: Google Pixel 3 (DT)
Workqueue: events_unbound deferred_probe_work_func
Call trace:
 dump_backtrace+0xa0/0xfc
 show_stack+0x18/0x24
 dump_stack_lvl+0x60/0xac
 dump_stack+0x18/0x24
 print_unlock_imbalance_bug+0x130/0x148
 lock_release+0x270/0x300
 __mutex_unlock_slowpath+0x48/0x2cc
 mutex_unlock+0x20/0x2c
 gpi_alloc_chan_resources+0x108/0x5bc
 dma_chan_get+0x84/0x188
 dma_get_slave_channel+0x5c/0x10c
 gpi_of_dma_xlate+0x110/0x1a0
 of_dma_request_slave_channel+0x174/0x280
 dma_request_chan+0x3c/0x2d4
 geni_i2c_probe+0x544/0x63c
 platform_probe+0x68/0xc4
 really_probe+0x148/0x2ac
 __driver_probe_device+0x78/0xe0
 driver_probe_device+0x3c/0x160
 __device_attach_driver+0xb8/0x138
 bus_for_each_drv+0x84/0xe0
 __device_attach+0x9c/0x188
 device_initial_probe+0x14/0x20
 bus_probe_device+0xac/0xb0
 device_add+0x60c/0x7d8
 of_device_add+0x44/0x60
 of_platform_device_create_pdata+0x90/0x124
 of_platform_bus_create+0x15c/0x3c8
 of_platform_populate+0x58/0xf8
 devm_of_platform_populate+0x58/0xbc
 geni_se_probe+0xf0/0x164
 platform_probe+0x68/0xc4
 really_probe+0x148/0x2ac
 __driver_probe_device+0x78/0xe0
 driver_probe_device+0x3c/0x160
 __device_attach_driver+0xb8/0x138
 bus_for_each_drv+0x84/0xe0
 __device_attach+0x9c/0x188
 device_initial_probe+0x14/0x20
 bus_probe_device+0xac/0xb0
 deferred_probe_work_func+0x8c/0xc8
 process_one_work+0x2bc/0x594
 worker_thread+0x228/0x438
 kthread+0x108/0x10c
 ret_from_fork+0x10/0x20

Fixes: 5d0c353 ("dmaengine: qcom: Add GPI dma driver")
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
Link: https://lore.kernel.org/r/20230409233355.453741-1-dmitry.baryshkov@linaro.org
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
mingzhangqun pushed a commit to mingzhangqun/st-linux that referenced this pull request Mar 23, 2024
[ Upstream commit 05bb016 ]

ACPICA commit 770653e3ba67c30a629ca7d12e352d83c2541b1e

Before this change we see the following UBSAN stack trace in Fuchsia:

  #0    0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
  STMicroelectronics#1.2  0x000020d0f660777f in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x3d77f
  STMicroelectronics#1.1  0x000020d0f660777f in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x3d77f
  STMicroelectronics#1    0x000020d0f660777f in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:387 <libclang_rt.asan.so>+0x3d77f
  STMicroelectronics#2    0x000020d0f660b96d in handlepointer_overflow_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:809 <libclang_rt.asan.so>+0x4196d
  STMicroelectronics#3    0x000020d0f660b50d in compiler-rt/lib/ubsan/ubsan_handlers.cpp:815 <libclang_rt.asan.so>+0x4150d
  STMicroelectronics#4    0x000021e4213b3302 in acpi_ds_init_aml_walk(struct acpi_walk_state*, union acpi_parse_object*, struct acpi_namespace_node*, u8*, u32, struct acpi_evaluate_info*, u8) ../../third_party/acpica/source/components/dispatcher/dswstate.c:682 <platform-bus-x86.so>+0x233302
  STMicroelectronics#5    0x000021e4213e2369 in acpi_ds_call_control_method(struct acpi_thread_state*, struct acpi_walk_state*, union acpi_parse_object*) ../../third_party/acpica/source/components/dispatcher/dsmethod.c:605 <platform-bus-x86.so>+0x262369
  STMicroelectronics#6    0x000021e421437fac in acpi_ps_parse_aml(struct acpi_walk_state*) ../../third_party/acpica/source/components/parser/psparse.c:550 <platform-bus-x86.so>+0x2b7fac
  STMicroelectronics#7    0x000021e4214464d2 in acpi_ps_execute_method(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/parser/psxface.c:244 <platform-bus-x86.so>+0x2c64d2
  STMicroelectronics#8    0x000021e4213aa052 in acpi_ns_evaluate(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/namespace/nseval.c:250 <platform-bus-x86.so>+0x22a052
  STMicroelectronics#9    0x000021e421413dd8 in acpi_ns_init_one_device(acpi_handle, u32, void*, void**) ../../third_party/acpica/source/components/namespace/nsinit.c:735 <platform-bus-x86.so>+0x293dd8
  STMicroelectronics#10   0x000021e421429e98 in acpi_ns_walk_namespace(acpi_object_type, acpi_handle, u32, u32, acpi_walk_callback, acpi_walk_callback, void*, void**) ../../third_party/acpica/source/components/namespace/nswalk.c:298 <platform-bus-x86.so>+0x2a9e98
  STMicroelectronics#11   0x000021e4214131ac in acpi_ns_initialize_devices(u32) ../../third_party/acpica/source/components/namespace/nsinit.c:268 <platform-bus-x86.so>+0x2931ac
  STMicroelectronics#12   0x000021e42147c40d in acpi_initialize_objects(u32) ../../third_party/acpica/source/components/utilities/utxfinit.c:304 <platform-bus-x86.so>+0x2fc40d
  STMicroelectronics#13   0x000021e42126d603 in acpi::acpi_impl::initialize_acpi(acpi::acpi_impl*) ../../src/devices/board/lib/acpi/acpi-impl.cc:224 <platform-bus-x86.so>+0xed603

Add a simple check that avoids incrementing a pointer by zero, but
otherwise behaves as before. Note that our findings are against ACPICA
20221020, but the same code exists on master.

Link: acpica/acpica@770653e3
Signed-off-by: Bob Moore <robert.moore@intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
mingzhangqun pushed a commit to mingzhangqun/st-linux that referenced this pull request Mar 23, 2024
[ Upstream commit 4f082a7 ]

This combines the overflow and boundary check so that all attribute size
will be properly examined while enumerating them.

[  169.181521] BUG: KASAN: slab-out-of-bounds in run_unpack+0x2e3/0x570
[  169.183161] Read of size 1 at addr ffff8880094b6240 by task mount/247
[  169.184046]
[  169.184925] CPU: 0 PID: 247 Comm: mount Not tainted 6.0.0-rc7+ STMicroelectronics#3
[  169.185908] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014
[  169.187066] Call Trace:
[  169.187492]  <TASK>
[  169.188049]  dump_stack_lvl+0x49/0x63
[  169.188495]  print_report.cold+0xf5/0x689
[  169.188964]  ? run_unpack+0x2e3/0x570
[  169.189331]  kasan_report+0xa7/0x130
[  169.189714]  ? run_unpack+0x2e3/0x570
[  169.190079]  __asan_load1+0x51/0x60
[  169.190634]  run_unpack+0x2e3/0x570
[  169.191290]  ? run_pack+0x840/0x840
[  169.191569]  ? run_lookup_entry+0xb3/0x1f0
[  169.192443]  ? mi_enum_attr+0x20a/0x230
[  169.192886]  run_unpack_ex+0xad/0x3e0
[  169.193276]  ? run_unpack+0x570/0x570
[  169.193557]  ? ni_load_mi+0x80/0x80
[  169.193889]  ? debug_smp_processor_id+0x17/0x20
[  169.194236]  ? mi_init+0x4a/0x70
[  169.194496]  attr_load_runs_vcn+0x166/0x1c0
[  169.194851]  ? attr_data_write_resident+0x250/0x250
[  169.195188]  mi_read+0x133/0x2c0
[  169.195481]  ntfs_iget5+0x277/0x1780
[  169.196017]  ? call_rcu+0x1c7/0x330
[  169.196392]  ? ntfs_get_block_bmap+0x70/0x70
[  169.196708]  ? evict+0x223/0x280
[  169.197014]  ? __kmalloc+0x33/0x540
[  169.197305]  ? wnd_init+0x15b/0x1b0
[  169.197599]  ntfs_fill_super+0x1026/0x1ba0
[  169.197994]  ? put_ntfs+0x1d0/0x1d0
[  169.198299]  ? vsprintf+0x20/0x20
[  169.198583]  ? mutex_unlock+0x81/0xd0
[  169.198930]  ? set_blocksize+0x95/0x150
[  169.199269]  get_tree_bdev+0x232/0x370
[  169.199750]  ? put_ntfs+0x1d0/0x1d0
[  169.200094]  ntfs_fs_get_tree+0x15/0x20
[  169.200431]  vfs_get_tree+0x4c/0x130
[  169.200714]  path_mount+0x654/0xfe0
[  169.201067]  ? putname+0x80/0xa0
[  169.201358]  ? finish_automount+0x2e0/0x2e0
[  169.201965]  ? putname+0x80/0xa0
[  169.202445]  ? kmem_cache_free+0x1c4/0x440
[  169.203075]  ? putname+0x80/0xa0
[  169.203414]  do_mount+0xd6/0xf0
[  169.203719]  ? path_mount+0xfe0/0xfe0
[  169.203977]  ? __kasan_check_write+0x14/0x20
[  169.204382]  __x64_sys_mount+0xca/0x110
[  169.204711]  do_syscall_64+0x3b/0x90
[  169.205059]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
[  169.205571] RIP: 0033:0x7f67a80e948a
[  169.206327] Code: 48 8b 0d 11 fa 2a 00 f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 49 89 ca b8 a5 00 00 008
[  169.208296] RSP: 002b:00007ffddf020f58 EFLAGS: 00000202 ORIG_RAX: 00000000000000a5
[  169.209253] RAX: ffffffffffffffda RBX: 000055e2547a6060 RCX: 00007f67a80e948a
[  169.209777] RDX: 000055e2547a6260 RSI: 000055e2547a62e0 RDI: 000055e2547aeaf0
[  169.210342] RBP: 0000000000000000 R08: 000055e2547a6280 R09: 0000000000000020
[  169.210843] R10: 00000000c0ed0000 R11: 0000000000000202 R12: 000055e2547aeaf0
[  169.211307] R13: 000055e2547a6260 R14: 0000000000000000 R15: 00000000ffffffff
[  169.211913]  </TASK>
[  169.212304]
[  169.212680] Allocated by task 0:
[  169.212963] (stack is not available)
[  169.213200]
[  169.213472] The buggy address belongs to the object at ffff8880094b5e00
[  169.213472]  which belongs to the cache UDP of size 1152
[  169.214095] The buggy address is located 1088 bytes inside of
[  169.214095]  1152-byte region [ffff8880094b5e00, ffff8880094b6280)
[  169.214639]
[  169.215004] The buggy address belongs to the physical page:
[  169.215766] page:000000002e324c8c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x94b4
[  169.218412] head:000000002e324c8c order:2 compound_mapcount:0 compound_pincount:0
[  169.219078] flags: 0xfffffc0010200(slab|head|node=0|zone=1|lastcpupid=0x1fffff)
[  169.220272] raw: 000fffffc0010200 0000000000000000 dead000000000122 ffff888002409b40
[  169.221006] raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
[  169.222320] page dumped because: kasan: bad access detected
[  169.222922]
[  169.223119] Memory state around the buggy address:
[  169.224056]  ffff8880094b6100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  169.224908]  ffff8880094b6180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  169.225677] >ffff8880094b6200: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  169.226445]                                            ^
[  169.227055]  ffff8880094b6280: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
[  169.227638]  ffff8880094b6300: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb

Signed-off-by: Edward Lo <edward.lo@ambergroup.io>
Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
mingzhangqun pushed a commit to mingzhangqun/st-linux that referenced this pull request Mar 23, 2024
commit 614ce6a upstream.

When the dwc3 device is runtime suspended, various required clocks are in
disabled state and it is not guaranteed that access to any registers would
work. Depending on the SoC glue, a register read could be as benign as
returning 0 or be fatal enough to hang the system.

In order to prevent such scenarios of fatal errors, make sure to resume
dwc3 then allow the function to proceed.

Fixes: 72246da ("usb: Introduce DesignWare USB3 DRD Driver")
Cc: stable@vger.kernel.org STMicroelectronics#3.2: 30332ee: debugfs: regset32: Add Runtime PM support
Signed-off-by: Udipto Goswami <quic_ugoswami@quicinc.com>
Reviewed-by: Johan Hovold <johan+linaro@kernel.org>
Tested-by: Johan Hovold <johan+linaro@kernel.org>
Acked-by: Thinh Nguyen <Thinh.Nguyen@synopsys.com>
Link: https://lore.kernel.org/r/20230509144836.6803-1-quic_ugoswami@quicinc.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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