limit non-mapping packets in subflow to 64KB #4

cpaasch · 2013-08-13T14:44:58Z

It may be possible, that all DSS-mappings are stripped from the packets. We
have to limit the storage of these packets up to 64KB of payload (because the
DSS-mapping length is on 16bit).
Upon reception of 64KB of non-mapped, in-order data on the subflow we may
fallback on this subflow. As there is really an issue on this subflow.

commit e8d0527 upstream. commit 2f7021a "cpufreq: protect 'policy->cpus' from offlining during __gov_queue_work()" caused a regression in CPU hotplug, because it lead to a deadlock between cpufreq governor worker thread and the CPU hotplug writer task. Lockdep splat corresponding to this deadlock is shown below: [ 60.277396] ====================================================== [ 60.277400] [ INFO: possible circular locking dependency detected ] [ 60.277407] 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744 Not tainted [ 60.277411] ------------------------------------------------------- [ 60.277417] bash/2225 is trying to acquire lock: [ 60.277422] ((&(&j_cdbs->work)->work)){+.+...}, at: [<ffffffff810621b5>] flush_work+0x5/0x280 [ 60.277444] but task is already holding lock: [ 60.277449] (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60 [ 60.277465] which lock already depends on the new lock. [ 60.277472] the existing dependency chain (in reverse order) is: [ 60.277477] -> #2 (cpu_hotplug.lock){+.+.+.}: [ 60.277490] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200 [ 60.277503] [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410 [ 60.277514] [<ffffffff81042cbc>] get_online_cpus+0x3c/0x60 [ 60.277522] [<ffffffff814b842a>] gov_queue_work+0x2a/0xb0 [ 60.277532] [<ffffffff814b7891>] cs_dbs_timer+0xc1/0xe0 [ 60.277543] [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0 [ 60.277552] [<ffffffff81063d31>] worker_thread+0x121/0x3a0 [ 60.277560] [<ffffffff8106ae2b>] kthread+0xdb/0xe0 [ 60.277569] [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0 [ 60.277580] -> #1 (&j_cdbs->timer_mutex){+.+...}: [ 60.277592] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200 [ 60.277600] [<ffffffff815b6157>] mutex_lock_nested+0x67/0x410 [ 60.277608] [<ffffffff814b785d>] cs_dbs_timer+0x8d/0xe0 [ 60.277616] [<ffffffff8106302d>] process_one_work+0x1cd/0x6a0 [ 60.277624] [<ffffffff81063d31>] worker_thread+0x121/0x3a0 [ 60.277633] [<ffffffff8106ae2b>] kthread+0xdb/0xe0 [ 60.277640] [<ffffffff815bb96c>] ret_from_fork+0x7c/0xb0 [ 60.277649] -> #0 ((&(&j_cdbs->work)->work)){+.+...}: [ 60.277661] [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30 [ 60.277669] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200 [ 60.277677] [<ffffffff810621ed>] flush_work+0x3d/0x280 [ 60.277685] [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120 [ 60.277693] [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20 [ 60.277701] [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0 [ 60.277709] [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20 [ 60.277719] [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100 [ 60.277728] [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0 [ 60.277737] [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c [ 60.277747] [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110 [ 60.277759] [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10 [ 60.277768] [<ffffffff815a0a68>] _cpu_down+0x88/0x330 [ 60.277779] [<ffffffff815a0d46>] cpu_down+0x36/0x50 [ 60.277788] [<ffffffff815a2748>] store_online+0x98/0xd0 [ 60.277796] [<ffffffff81452a28>] dev_attr_store+0x18/0x30 [ 60.277806] [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150 [ 60.277818] [<ffffffff8116806d>] vfs_write+0xbd/0x1f0 [ 60.277826] [<ffffffff811686fc>] SyS_write+0x4c/0xa0 [ 60.277834] [<ffffffff815bbbbe>] tracesys+0xd0/0xd5 [ 60.277842] other info that might help us debug this: [ 60.277848] Chain exists of: (&(&j_cdbs->work)->work) --> &j_cdbs->timer_mutex --> cpu_hotplug.lock [ 60.277864] Possible unsafe locking scenario: [ 60.277869] CPU0 CPU1 [ 60.277873] ---- ---- [ 60.277877] lock(cpu_hotplug.lock); [ 60.277885] lock(&j_cdbs->timer_mutex); [ 60.277892] lock(cpu_hotplug.lock); [ 60.277900] lock((&(&j_cdbs->work)->work)); [ 60.277907] *** DEADLOCK *** [ 60.277915] 6 locks held by bash/2225: [ 60.277919] #0: (sb_writers#6){.+.+.+}, at: [<ffffffff81168173>] vfs_write+0x1c3/0x1f0 [ 60.277937] #1: (&buffer->mutex){+.+.+.}, at: [<ffffffff811d9e3c>] sysfs_write_file+0x3c/0x150 [ 60.277954] #2: (s_active#61){.+.+.+}, at: [<ffffffff811d9ec3>] sysfs_write_file+0xc3/0x150 [ 60.277972] #3: (x86_cpu_hotplug_driver_mutex){+.+...}, at: [<ffffffff81024cf7>] cpu_hotplug_driver_lock+0x17/0x20 [ 60.277990] #4: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff815a0d32>] cpu_down+0x22/0x50 [ 60.278007] #5: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff81042d8b>] cpu_hotplug_begin+0x2b/0x60 [ 60.278023] stack backtrace: [ 60.278031] CPU: 3 PID: 2225 Comm: bash Not tainted 3.10.0-rc7-dbg-01385-g241fd04-dirty #1744 [ 60.278037] Hardware name: Acer Aspire 5741G /Aspire 5741G , BIOS V1.20 02/08/2011 [ 60.278042] ffffffff8204e110 ffff88014df6b9f8 ffffffff815b3d90 ffff88014df6ba38 [ 60.278055] ffffffff815b0a8d ffff880150ed3f60 ffff880150ed4770 3871c4002c8980b2 [ 60.278068] ffff880150ed4748 ffff880150ed4770 ffff880150ed3f60 ffff88014df6bb00 [ 60.278081] Call Trace: [ 60.278091] [<ffffffff815b3d90>] dump_stack+0x19/0x1b [ 60.278101] [<ffffffff815b0a8d>] print_circular_bug+0x2b6/0x2c5 [ 60.278111] [<ffffffff810ab826>] __lock_acquire+0x1766/0x1d30 [ 60.278123] [<ffffffff81067e08>] ? __kernel_text_address+0x58/0x80 [ 60.278134] [<ffffffff810ac6d4>] lock_acquire+0xa4/0x200 [ 60.278142] [<ffffffff810621b5>] ? flush_work+0x5/0x280 [ 60.278151] [<ffffffff810621ed>] flush_work+0x3d/0x280 [ 60.278159] [<ffffffff810621b5>] ? flush_work+0x5/0x280 [ 60.278169] [<ffffffff810a9b14>] ? mark_held_locks+0x94/0x140 [ 60.278178] [<ffffffff81062d77>] ? __cancel_work_timer+0x77/0x120 [ 60.278188] [<ffffffff810a9cbd>] ? trace_hardirqs_on_caller+0xfd/0x1c0 [ 60.278196] [<ffffffff81062d8a>] __cancel_work_timer+0x8a/0x120 [ 60.278206] [<ffffffff81062e53>] cancel_delayed_work_sync+0x13/0x20 [ 60.278214] [<ffffffff814b89d9>] cpufreq_governor_dbs+0x529/0x6f0 [ 60.278225] [<ffffffff814b76a7>] cs_cpufreq_governor_dbs+0x17/0x20 [ 60.278234] [<ffffffff814b5df8>] __cpufreq_governor+0x48/0x100 [ 60.278244] [<ffffffff814b6b80>] __cpufreq_remove_dev.isra.14+0x80/0x3c0 [ 60.278255] [<ffffffff815adc0d>] cpufreq_cpu_callback+0x38/0x4c [ 60.278265] [<ffffffff81071a4d>] notifier_call_chain+0x5d/0x110 [ 60.278275] [<ffffffff81071b0e>] __raw_notifier_call_chain+0xe/0x10 [ 60.278284] [<ffffffff815a0a68>] _cpu_down+0x88/0x330 [ 60.278292] [<ffffffff81024cf7>] ? cpu_hotplug_driver_lock+0x17/0x20 [ 60.278302] [<ffffffff815a0d46>] cpu_down+0x36/0x50 [ 60.278311] [<ffffffff815a2748>] store_online+0x98/0xd0 [ 60.278320] [<ffffffff81452a28>] dev_attr_store+0x18/0x30 [ 60.278329] [<ffffffff811d9edb>] sysfs_write_file+0xdb/0x150 [ 60.278337] [<ffffffff8116806d>] vfs_write+0xbd/0x1f0 [ 60.278347] [<ffffffff81185950>] ? fget_light+0x320/0x4b0 [ 60.278355] [<ffffffff811686fc>] SyS_write+0x4c/0xa0 [ 60.278364] [<ffffffff815bbbbe>] tracesys+0xd0/0xd5 [ 60.280582] smpboot: CPU 1 is now offline The intention of that commit was to avoid warnings during CPU hotplug, which indicated that offline CPUs were getting IPIs from the cpufreq governor's work items. But the real root-cause of that problem was commit a66b2e5 (cpufreq: Preserve sysfs files across suspend/resume) because it totally skipped all the cpufreq callbacks during CPU hotplug in the suspend/resume path, and hence it never actually shut down the cpufreq governor's worker threads during CPU offline in the suspend/resume path. Reflecting back, the reason why we never suspected that commit as the root-cause earlier, was that the original issue was reported with just the halt command and nobody had brought in suspend/resume to the equation. The reason for _that_ in turn, as it turns out, is that earlier halt/shutdown was being done by disabling non-boot CPUs while tasks were frozen, just like suspend/resume.... but commit cf7df37 (reboot: migrate shutdown/reboot to boot cpu) which came somewhere along that very same time changed that logic: shutdown/halt no longer takes CPUs offline. Thus, the test-cases for reproducing the bug were vastly different and thus we went totally off the trail. Overall, it was one hell of a confusion with so many commits affecting each other and also affecting the symptoms of the problems in subtle ways. Finally, now since the original problematic commit (a66b2e5) has been completely reverted, revert this intermediate fix too (2f7021a), to fix the CPU hotplug deadlock. Phew! Reported-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com> Reported-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: Peter Wu <lekensteyn@gmail.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit 058ebd0 upstream. Jiri managed to trigger this warning: [] ====================================================== [] [ INFO: possible circular locking dependency detected ] [] 3.10.0+ #228 Tainted: G W [] ------------------------------------------------------- [] p/6613 is trying to acquire lock: [] (rcu_node_0){..-...}, at: [<ffffffff810ca797>] rcu_read_unlock_special+0xa7/0x250 [] [] but task is already holding lock: [] (&ctx->lock){-.-...}, at: [<ffffffff810f2879>] perf_lock_task_context+0xd9/0x2c0 [] [] which lock already depends on the new lock. [] [] the existing dependency chain (in reverse order) is: [] [] -> #4 (&ctx->lock){-.-...}: [] -> #3 (&rq->lock){-.-.-.}: [] -> #2 (&p->pi_lock){-.-.-.}: [] -> #1 (&rnp->nocb_gp_wq[1]){......}: [] -> #0 (rcu_node_0){..-...}: Paul was quick to explain that due to preemptible RCU we cannot call rcu_read_unlock() while holding scheduler (or nested) locks when part of the read side critical section was preemptible. Therefore solve it by making the entire RCU read side non-preemptible. Also pull out the retry from under the non-preempt to play nice with RT. Reported-by: Jiri Olsa <jolsa@redhat.com> Helped-out-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 905a6f9 ] Otherwise we end up dereferencing the already freed net->ipv6.mrt pointer which leads to a panic (from Srivatsa S. Bhat): BUG: unable to handle kernel paging request at ffff882018552020 IP: [<ffffffffa0366b02>] ip6mr_sk_done+0x32/0xb0 [ipv6] PGD 290a067 PUD 207ffe0067 PMD 207ff1d067 PTE 8000002018552060 Oops: 0000 [#1] SMP DEBUG_PAGEALLOC Modules linked in: ebtable_nat ebtables nfs fscache nf_conntrack_ipv4 nf_defrag_ipv4 ipt_REJECT xt_CHECKSUM iptable_mangle iptable_filter ip_tables nfsd lockd nfs_acl exportfs auth_rpcgss autofs4 sunrpc 8021q garp bridge stp llc ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 xt_state nf_conntrack ip6table_filter +ip6_tables ipv6 vfat fat vhost_net macvtap macvlan vhost tun kvm_intel kvm uinput iTCO_wdt iTCO_vendor_support cdc_ether usbnet mii microcode i2c_i801 i2c_core lpc_ich mfd_core shpchp ioatdma dca mlx4_core be2net wmi acpi_cpufreq mperf ext4 jbd2 mbcache dm_mirror dm_region_hash dm_log dm_mod CPU: 0 PID: 7 Comm: kworker/u33:0 Not tainted 3.11.0-rc1-ea45e-a #4 Hardware name: IBM -[8737R2A]-/00Y2738, BIOS -[B2E120RUS-1.20]- 11/30/2012 Workqueue: netns cleanup_net task: ffff8810393641c0 ti: ffff881039366000 task.ti: ffff881039366000 RIP: 0010:[<ffffffffa0366b02>] [<ffffffffa0366b02>] ip6mr_sk_done+0x32/0xb0 [ipv6] RSP: 0018:ffff881039367bd8 EFLAGS: 00010286 RAX: ffff881039367fd8 RBX: ffff882018552000 RCX: dead000000200200 RDX: 0000000000000000 RSI: ffff881039367b68 RDI: ffff881039367b68 RBP: ffff881039367bf8 R08: ffff881039367b68 R09: 2222222222222222 R10: 2222222222222222 R11: 2222222222222222 R12: ffff882015a7a040 R13: ffff882014eb89c0 R14: ffff8820289e2800 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff88103fc00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff882018552020 CR3: 0000000001c0b000 CR4: 00000000000407f0 Stack: ffff881039367c18 ffff882014eb89c0 ffff882015e28c00 0000000000000000 ffff881039367c18 ffffffffa034d9d1 ffff8820289e2800 ffff882014eb89c0 ffff881039367c58 ffffffff815bdecb ffffffff815bddf2 ffff882014eb89c0 Call Trace: [<ffffffffa034d9d1>] rawv6_close+0x21/0x40 [ipv6] [<ffffffff815bdecb>] inet_release+0xfb/0x220 [<ffffffff815bddf2>] ? inet_release+0x22/0x220 [<ffffffffa032686f>] inet6_release+0x3f/0x50 [ipv6] [<ffffffff8151c1d9>] sock_release+0x29/0xa0 [<ffffffff81525520>] sk_release_kernel+0x30/0x70 [<ffffffffa034f14b>] icmpv6_sk_exit+0x3b/0x80 [ipv6] [<ffffffff8152fff9>] ops_exit_list+0x39/0x60 [<ffffffff815306fb>] cleanup_net+0xfb/0x1a0 [<ffffffff81075e3a>] process_one_work+0x1da/0x610 [<ffffffff81075dc9>] ? process_one_work+0x169/0x610 [<ffffffff81076390>] worker_thread+0x120/0x3a0 [<ffffffff81076270>] ? process_one_work+0x610/0x610 [<ffffffff8107da2e>] kthread+0xee/0x100 [<ffffffff8107d940>] ? __init_kthread_worker+0x70/0x70 [<ffffffff8162a99c>] ret_from_fork+0x7c/0xb0 [<ffffffff8107d940>] ? __init_kthread_worker+0x70/0x70 Code: 20 48 89 5d e8 4c 89 65 f0 4c 89 6d f8 66 66 66 66 90 4c 8b 67 30 49 89 fd e8 db 3c 1e e1 49 8b 9c 24 90 08 00 00 48 85 db 74 06 <4c> 39 6b 20 74 20 bb f3 ff ff ff e8 8e 3c 1e e1 89 d8 4c 8b 65 RIP [<ffffffffa0366b02>] ip6mr_sk_done+0x32/0xb0 [ipv6] RSP <ffff881039367bd8> CR2: ffff882018552020 Reported-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Tested-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Hannes Frederic Sowa <hannes@stressinduktion.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit ea3768b upstream. We used to keep the port's char device structs and the /sys entries around till the last reference to the port was dropped. This is actually unnecessary, and resulted in buggy behaviour: 1. Open port in guest 2. Hot-unplug port 3. Hot-plug a port with the same 'name' property as the unplugged one This resulted in hot-plug being unsuccessful, as a port with the same name already exists (even though it was unplugged). This behaviour resulted in a warning message like this one: -------------------8<--------------------------------------- WARNING: at fs/sysfs/dir.c:512 sysfs_add_one+0xc9/0x130() (Not tainted) Hardware name: KVM sysfs: cannot create duplicate filename '/devices/pci0000:00/0000:00:04.0/virtio0/virtio-ports/vport0p1' Call Trace: [<ffffffff8106b607>] ? warn_slowpath_common+0x87/0xc0 [<ffffffff8106b6f6>] ? warn_slowpath_fmt+0x46/0x50 [<ffffffff811f2319>] ? sysfs_add_one+0xc9/0x130 [<ffffffff811f23e8>] ? create_dir+0x68/0xb0 [<ffffffff811f2469>] ? sysfs_create_dir+0x39/0x50 [<ffffffff81273129>] ? kobject_add_internal+0xb9/0x260 [<ffffffff812733d8>] ? kobject_add_varg+0x38/0x60 [<ffffffff812734b4>] ? kobject_add+0x44/0x70 [<ffffffff81349de4>] ? get_device_parent+0xf4/0x1d0 [<ffffffff8134b389>] ? device_add+0xc9/0x650 -------------------8<--------------------------------------- Instead of relying on guest applications to release all references to the ports, we should go ahead and unregister the port from all the core layers. Any open/read calls on the port will then just return errors, and an unplug/plug operation on the host will succeed as expected. This also caused buggy behaviour in case of the device removal (not just a port): when the device was removed (which means all ports on that device are removed automatically as well), the ports with active users would clean up only when the last references were dropped -- and it would be too late then to be referencing char device pointers, resulting in oopses: -------------------8<--------------------------------------- PID: 6162 TASK: ffff8801147ad500 CPU: 0 COMMAND: "cat" #0 [ffff88011b9d5a90] machine_kexec at ffffffff8103232b #1 [ffff88011b9d5af0] crash_kexec at ffffffff810b9322 #2 [ffff88011b9d5bc0] oops_end at ffffffff814f4a50 #3 [ffff88011b9d5bf0] die at ffffffff8100f26b #4 [ffff88011b9d5c20] do_general_protection at ffffffff814f45e2 #5 [ffff88011b9d5c50] general_protection at ffffffff814f3db5 [exception RIP: strlen+2] RIP: ffffffff81272ae2 RSP: ffff88011b9d5d00 RFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff880118901c18 RCX: 0000000000000000 RDX: ffff88011799982c RSI: 00000000000000d0 RDI: 3a303030302f3030 RBP: ffff88011b9d5d38 R8: 0000000000000006 R9: ffffffffa0134500 R10: 0000000000001000 R11: 0000000000001000 R12: ffff880117a1cc10 R13: 00000000000000d0 R14: 0000000000000017 R15: ffffffff81aff700 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #6 [ffff88011b9d5d00] kobject_get_path at ffffffff8126dc5d #7 [ffff88011b9d5d40] kobject_uevent_env at ffffffff8126e551 #8 [ffff88011b9d5dd0] kobject_uevent at ffffffff8126e9eb #9 [ffff88011b9d5de0] device_del at ffffffff813440c7 -------------------8<--------------------------------------- So clean up when we have all the context, and all that's left to do when the references to the port have dropped is to free up the port struct itself. Reported-by: chayang <chayang@redhat.com> Reported-by: YOGANANTH SUBRAMANIAN <anantyog@in.ibm.com> Reported-by: FuXiangChun <xfu@redhat.com> Reported-by: Qunfang Zhang <qzhang@redhat.com> Reported-by: Sibiao Luo <sluo@redhat.com> Signed-off-by: Amit Shah <amit.shah@redhat.com> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

BugLink: http://bugs.launchpad.net/bugs/1204666 commit 058ebd0 upstream. Jiri managed to trigger this warning: [] ====================================================== [] [ INFO: possible circular locking dependency detected ] [] 3.10.0+ #228 Tainted: G W [] ------------------------------------------------------- [] p/6613 is trying to acquire lock: [] (rcu_node_0){..-...}, at: [<ffffffff810ca797>] rcu_read_unlock_special+0xa7/0x250 [] [] but task is already holding lock: [] (&ctx->lock){-.-...}, at: [<ffffffff810f2879>] perf_lock_task_context+0xd9/0x2c0 [] [] which lock already depends on the new lock. [] [] the existing dependency chain (in reverse order) is: [] [] -> #4 (&ctx->lock){-.-...}: [] -> #3 (&rq->lock){-.-.-.}: [] -> #2 (&p->pi_lock){-.-.-.}: [] -> #1 (&rnp->nocb_gp_wq[1]){......}: [] -> #0 (rcu_node_0){..-...}: Paul was quick to explain that due to preemptible RCU we cannot call rcu_read_unlock() while holding scheduler (or nested) locks when part of the read side critical section was preemptible. Therefore solve it by making the entire RCU read side non-preemptible. Also pull out the retry from under the non-preempt to play nice with RT. Reported-by: Jiri Olsa <jolsa@redhat.com> Helped-out-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Signed-off-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Ingo Molnar <mingo@kernel.org> Signed-off-by: Kamal Mostafa <kamal@canonical.com> Signed-off-by: Steve Conklin <sconklin@canonical.com>

On architectures where cputime_t is 64 bit type, is possible to trigger divide by zero on do_div(temp, (__force u32) total) line, if total is a non zero number but has lower 32 bit's zeroed. Removing casting is not a good solution since some do_div() implementations do cast to u32 internally. This problem can be triggered in practice on very long lived processes: PID: 2331 TASK: ffff880472814b00 CPU: 2 COMMAND: "oraagent.bin" #0 [ffff880472a51b70] machine_kexec at ffffffff8103214b multipath-tcp#1 [ffff880472a51bd0] crash_kexec at ffffffff810b91c2 multipath-tcp#2 [ffff880472a51ca0] oops_end at ffffffff814f0b00 multipath-tcp#3 [ffff880472a51cd0] die at ffffffff8100f26b multipath-tcp#4 [ffff880472a51d00] do_trap at ffffffff814f03f4 multipath-tcp#5 [ffff880472a51d60] do_divide_error at ffffffff8100cfff multipath-tcp#6 [ffff880472a51e00] divide_error at ffffffff8100be7b [exception RIP: thread_group_times+0x56] RIP: ffffffff81056a16 RSP: ffff880472a51eb8 RFLAGS: 00010046 RAX: bc3572c9fe12d194 RBX: ffff880874150800 RCX: 0000000110266fad RDX: 0000000000000000 RSI: ffff880472a51eb8 RDI: 001038ae7d9633dc RBP: ffff880472a51ef8 R8: 00000000b10a3a64 R9: ffff880874150800 R10: 00007fcba27ab680 R11: 0000000000000202 R12: ffff880472a51f08 R13: ffff880472a51f10 R14: 0000000000000000 R15: 0000000000000007 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 multipath-tcp#7 [ffff880472a51f00] do_sys_times at ffffffff8108845d multipath-tcp#8 [ffff880472a51f40] sys_times at ffffffff81088524 multipath-tcp#9 [ffff880472a51f80] system_call_fastpath at ffffffff8100b0f2 RIP: 0000003808caac3a RSP: 00007fcba27ab6d8 RFLAGS: 00000202 RAX: 0000000000000064 RBX: ffffffff8100b0f2 RCX: 0000000000000000 RDX: 00007fcba27ab6e0 RSI: 000000000076d58e RDI: 00007fcba27ab6e0 RBP: 00007fcba27ab700 R8: 0000000000000020 R9: 000000000000091b R10: 00007fcba27ab680 R11: 0000000000000202 R12: 00007fff9ca41940 R13: 0000000000000000 R14: 00007fcba27ac9c0 R15: 00007fff9ca41940 ORIG_RAX: 0000000000000064 CS: 0033 SS: 002b Cc: stable@vger.kernel.org Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/20120808092714.GA3580@redhat.com Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

If SMP fails, we should always cancel security_timer delayed work. Otherwise, security_timer function may run after l2cap_conn object has been freed. This patch fixes the following warning reported by ODEBUG: WARNING: at lib/debugobjects.c:261 debug_print_object+0x7c/0x8d() Hardware name: Bochs ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x27 Modules linked in: btusb bluetooth Pid: 440, comm: kworker/u:2 Not tainted 3.5.0-rc1+ multipath-tcp#4 Call Trace: [<ffffffff81174600>] ? free_obj_work+0x4a/0x7f [<ffffffff81023eb8>] warn_slowpath_common+0x7e/0x97 [<ffffffff81023f65>] warn_slowpath_fmt+0x41/0x43 [<ffffffff811746b1>] debug_print_object+0x7c/0x8d [<ffffffff810394f0>] ? __queue_work+0x241/0x241 [<ffffffff81174fdd>] debug_check_no_obj_freed+0x92/0x159 [<ffffffff810ac08e>] slab_free_hook+0x6f/0x77 [<ffffffffa0019145>] ? l2cap_conn_del+0x148/0x157 [bluetooth] [<ffffffff810ae408>] kfree+0x59/0xac [<ffffffffa0019145>] l2cap_conn_del+0x148/0x157 [bluetooth] [<ffffffffa001b9a2>] l2cap_recv_frame+0xa77/0xfa4 [bluetooth] [<ffffffff810592f9>] ? trace_hardirqs_on_caller+0x112/0x1ad [<ffffffffa001c86c>] l2cap_recv_acldata+0xe2/0x264 [bluetooth] [<ffffffffa0002b2f>] hci_rx_work+0x235/0x33c [bluetooth] [<ffffffff81038dc3>] ? process_one_work+0x126/0x2fe [<ffffffff81038e22>] process_one_work+0x185/0x2fe [<ffffffff81038dc3>] ? process_one_work+0x126/0x2fe [<ffffffff81059f2e>] ? lock_acquired+0x1b5/0x1cf [<ffffffffa00028fa>] ? le_scan_work+0x11d/0x11d [bluetooth] [<ffffffff81036fb6>] ? spin_lock_irq+0x9/0xb [<ffffffff81039209>] worker_thread+0xcf/0x175 [<ffffffff8103913a>] ? rescuer_thread+0x175/0x175 [<ffffffff8103cfe0>] kthread+0x95/0x9d [<ffffffff812c5054>] kernel_threadi_helper+0x4/0x10 [<ffffffff812c36b0>] ? retint_restore_args+0x13/0x13 [<ffffffff8103cf4b>] ? flush_kthread_worker+0xdb/0xdb [<ffffffff812c5050>] ? gs_change+0x13/0x13 This bug can be reproduced using hctool lecc or l2test tools and bluetoothd not running. Signed-off-by: Andre Guedes <andre.guedes@openbossa.org> Signed-off-by: Gustavo Padovan <gustavo.padovan@collabora.co.uk>

Each page mapped in a process's address space must be correctly accounted for in _mapcount. Normally the rules for this are straightforward but hugetlbfs page table sharing is different. The page table pages at the PMD level are reference counted while the mapcount remains the same. If this accounting is wrong, it causes bugs like this one reported by Larry Woodman: kernel BUG at mm/filemap.c:135! invalid opcode: 0000 [multipath-tcp#1] SMP CPU 22 Modules linked in: bridge stp llc sunrpc binfmt_misc dcdbas microcode pcspkr acpi_pad acpi] Pid: 18001, comm: mpitest Tainted: G W 3.3.0+ multipath-tcp#4 Dell Inc. PowerEdge R620/07NDJ2 RIP: 0010:[<ffffffff8112cfed>] [<ffffffff8112cfed>] __delete_from_page_cache+0x15d/0x170 Process mpitest (pid: 18001, threadinfo ffff880428972000, task ffff880428b5cc20) Call Trace: delete_from_page_cache+0x40/0x80 truncate_hugepages+0x115/0x1f0 hugetlbfs_evict_inode+0x18/0x30 evict+0x9f/0x1b0 iput_final+0xe3/0x1e0 iput+0x3e/0x50 d_kill+0xf8/0x110 dput+0xe2/0x1b0 __fput+0x162/0x240 During fork(), copy_hugetlb_page_range() detects if huge_pte_alloc() shared page tables with the check dst_pte == src_pte. The logic is if the PMD page is the same, they must be shared. This assumes that the sharing is between the parent and child. However, if the sharing is with a different process entirely then this check fails as in this diagram: parent | ------------>pmd src_pte----------> data page ^ other--------->pmd--------------------| ^ child-----------| dst_pte For this situation to occur, it must be possible for Parent and Other to have faulted and failed to share page tables with each other. This is possible due to the following style of race. PROC A PROC B copy_hugetlb_page_range copy_hugetlb_page_range src_pte == huge_pte_offset src_pte == huge_pte_offset !src_pte so no sharing !src_pte so no sharing (time passes) hugetlb_fault hugetlb_fault huge_pte_alloc huge_pte_alloc huge_pmd_share huge_pmd_share LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) LOCK(i_mmap_mutex) find nothing, no sharing UNLOCK(i_mmap_mutex) pmd_alloc pmd_alloc LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) LOCK(instantiation_mutex) fault UNLOCK(instantiation_mutex) These two processes are not poing to the same data page but are not sharing page tables because the opportunity was missed. When either process later forks, the src_pte == dst pte is potentially insufficient. As the check falls through, the wrong PTE information is copied in (harmless but wrong) and the mapcount is bumped for a page mapped by a shared page table leading to the BUG_ON. This patch addresses the issue by moving pmd_alloc into huge_pmd_share which guarantees that the shared pud is populated in the same critical section as pmd. This also means that huge_pte_offset test in huge_pmd_share is serialized correctly now which in turn means that the success of the sharing will be higher as the racing tasks see the pud and pmd populated together. Race identified and changelog written mostly by Mel Gorman. {akpm@linux-foundation.org: attempt to make the huge_pmd_share() comment comprehensible, clean up coding style] Reported-by: Larry Woodman <lwoodman@redhat.com> Tested-by: Larry Woodman <lwoodman@redhat.com> Reviewed-by: Mel Gorman <mgorman@suse.de> Signed-off-by: Michal Hocko <mhocko@suse.cz> Reviewed-by: Rik van Riel <riel@redhat.com> Cc: David Gibson <david@gibson.dropbear.id.au> Cc: Ken Chen <kenchen@google.com> Cc: Cong Wang <xiyou.wangcong@gmail.com> Cc: Hillf Danton <dhillf@gmail.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

This moves ARM over to the asm-generic/unaligned.h header. This has the benefit of better code generated especially for ARMv7 on gcc 4.7+ compilers. As Arnd Bergmann, points out: The asm-generic version uses the "struct" version for native-endian unaligned access and the "byteshift" version for the opposite endianess. The current ARM version however uses the "byteshift" implementation for both. Thanks to Nicolas Pitre for the excellent analysis: Test case: int foo (int *x) { return get_unaligned(x); } long long bar (long long *x) { return get_unaligned(x); } With the current ARM version: foo: ldrb r3, [r0, multipath-tcp#2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, multipath-tcp#1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] ldrb r2, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov r3, r3, asl multipath-tcp#16 @ tmp154, MEM[(const u8 *)x_1(D) + 2B], ldrb r0, [r0, multipath-tcp#3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr r3, r3, r1, asl multipath-tcp#8 @, tmp155, tmp154, MEM[(const u8 *)x_1(D) + 1B], orr r3, r3, r2 @ tmp157, tmp155, MEM[(const u8 *)x_1(D)] orr r0, r3, r0, asl multipath-tcp#24 @,, tmp157, MEM[(const u8 *)x_1(D) + 3B], bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, mov r2, #0 @ tmp184, ldrb r5, [r0, multipath-tcp#6] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 6B], MEM[(const u8 *)x_1(D) + 6B] ldrb r4, [r0, multipath-tcp#5] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 5B], MEM[(const u8 *)x_1(D) + 5B] ldrb ip, [r0, multipath-tcp#2] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 2B], MEM[(const u8 *)x_1(D) + 2B] ldrb r1, [r0, multipath-tcp#4] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 4B], MEM[(const u8 *)x_1(D) + 4B] mov r5, r5, asl multipath-tcp#16 @ tmp175, MEM[(const u8 *)x_1(D) + 6B], ldrb r7, [r0, multipath-tcp#1] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 1B], MEM[(const u8 *)x_1(D) + 1B] orr r5, r5, r4, asl multipath-tcp#8 @, tmp176, tmp175, MEM[(const u8 *)x_1(D) + 5B], ldrb r6, [r0, multipath-tcp#7] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 7B], MEM[(const u8 *)x_1(D) + 7B] orr r5, r5, r1 @ tmp178, tmp176, MEM[(const u8 *)x_1(D) + 4B] ldrb r4, [r0, #0] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D)], MEM[(const u8 *)x_1(D)] mov ip, ip, asl multipath-tcp#16 @ tmp188, MEM[(const u8 *)x_1(D) + 2B], ldrb r1, [r0, multipath-tcp#3] @ zero_extendqisi2 @ MEM[(const u8 *)x_1(D) + 3B], MEM[(const u8 *)x_1(D) + 3B] orr ip, ip, r7, asl multipath-tcp#8 @, tmp189, tmp188, MEM[(const u8 *)x_1(D) + 1B], orr r3, r5, r6, asl multipath-tcp#24 @,, tmp178, MEM[(const u8 *)x_1(D) + 7B], orr ip, ip, r4 @ tmp191, tmp189, MEM[(const u8 *)x_1(D)] orr ip, ip, r1, asl multipath-tcp#24 @, tmp194, tmp191, MEM[(const u8 *)x_1(D) + 3B], mov r1, r3 @, orr r0, r2, ip @ tmp171, tmp184, tmp194 ldmfd sp!, {r4, r5, r6, r7} bx lr In both cases the code is slightly suboptimal. One may wonder why wasting r2 with the constant 0 in the second case for example. And all the mov's could be folded in subsequent orr's, etc. Now with the asm-generic version: foo: ldr r0, [r0, #0] @ unaligned @,* x bx lr @ bar: mov r3, r0 @ x, x ldr r0, [r0, #0] @ unaligned @,* x ldr r1, [r3, multipath-tcp#4] @ unaligned @, bx lr @ This is way better of course, but only because this was compiled for ARMv7. In this case the compiler knows that the hardware can do unaligned word access. This isn't that obvious for foo(), but if we remove the get_unaligned() from bar as follows: long long bar (long long *x) {return *x; } then the resulting code is: bar: ldmia r0, {r0, r1} @ x,, bx lr @ So this proves that the presumed aligned vs unaligned cases does have influence on the instructions the compiler may use and that the above unaligned code results are not just an accident. Still... this isn't fully conclusive without at least looking at the resulting assembly fron a pre ARMv6 compilation. Let's see with an ARMv5 target: foo: ldrb r3, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r1, [r0, multipath-tcp#1] @ zero_extendqisi2 @ tmp140, ldrb r2, [r0, multipath-tcp#2] @ zero_extendqisi2 @ tmp143, ldrb r0, [r0, multipath-tcp#3] @ zero_extendqisi2 @ tmp146, orr r3, r3, r1, asl multipath-tcp#8 @, tmp142, tmp139, tmp140, orr r3, r3, r2, asl multipath-tcp#16 @, tmp145, tmp142, tmp143, orr r0, r3, r0, asl multipath-tcp#24 @,, tmp145, tmp146, bx lr @ bar: stmfd sp!, {r4, r5, r6, r7} @, ldrb r2, [r0, #0] @ zero_extendqisi2 @ tmp139,* x ldrb r7, [r0, multipath-tcp#1] @ zero_extendqisi2 @ tmp140, ldrb r3, [r0, multipath-tcp#4] @ zero_extendqisi2 @ tmp149, ldrb r6, [r0, multipath-tcp#5] @ zero_extendqisi2 @ tmp150, ldrb r5, [r0, multipath-tcp#2] @ zero_extendqisi2 @ tmp143, ldrb r4, [r0, multipath-tcp#6] @ zero_extendqisi2 @ tmp153, ldrb r1, [r0, multipath-tcp#7] @ zero_extendqisi2 @ tmp156, ldrb ip, [r0, multipath-tcp#3] @ zero_extendqisi2 @ tmp146, orr r2, r2, r7, asl multipath-tcp#8 @, tmp142, tmp139, tmp140, orr r3, r3, r6, asl multipath-tcp#8 @, tmp152, tmp149, tmp150, orr r2, r2, r5, asl multipath-tcp#16 @, tmp145, tmp142, tmp143, orr r3, r3, r4, asl multipath-tcp#16 @, tmp155, tmp152, tmp153, orr r0, r2, ip, asl multipath-tcp#24 @,, tmp145, tmp146, orr r1, r3, r1, asl multipath-tcp#24 @,, tmp155, tmp156, ldmfd sp!, {r4, r5, r6, r7} bx lr Compared to the initial results, this is really nicely optimized and I couldn't do much better if I were to hand code it myself. Signed-off-by: Rob Herring <rob.herring@calxeda.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Tested-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Fixes following lockdep splat : [ 1614.734896] ============================================= [ 1614.734898] [ INFO: possible recursive locking detected ] [ 1614.734901] 3.6.0-rc3+ #782 Not tainted [ 1614.734903] --------------------------------------------- [ 1614.734905] swapper/11/0 is trying to acquire lock: [ 1614.734907] (slock-AF_INET){+.-...}, at: [<ffffffffa0209d72>] l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [ 1614.734920] [ 1614.734920] but task is already holding lock: [ 1614.734922] (slock-AF_INET){+.-...}, at: [<ffffffff815fce23>] tcp_v4_err+0x163/0x6b0 [ 1614.734932] [ 1614.734932] other info that might help us debug this: [ 1614.734935] Possible unsafe locking scenario: [ 1614.734935] [ 1614.734937] CPU0 [ 1614.734938] ---- [ 1614.734940] lock(slock-AF_INET); [ 1614.734943] lock(slock-AF_INET); [ 1614.734946] [ 1614.734946] *** DEADLOCK *** [ 1614.734946] [ 1614.734949] May be due to missing lock nesting notation [ 1614.734949] [ 1614.734952] 7 locks held by swapper/11/0: [ 1614.734954] #0: (rcu_read_lock){.+.+..}, at: [<ffffffff81592801>] __netif_receive_skb+0x251/0xd00 [ 1614.734964] multipath-tcp#1: (rcu_read_lock){.+.+..}, at: [<ffffffff815d319c>] ip_local_deliver_finish+0x4c/0x4e0 [ 1614.734972] multipath-tcp#2: (rcu_read_lock){.+.+..}, at: [<ffffffff8160d116>] icmp_socket_deliver+0x46/0x230 [ 1614.734982] multipath-tcp#3: (slock-AF_INET){+.-...}, at: [<ffffffff815fce23>] tcp_v4_err+0x163/0x6b0 [ 1614.734989] multipath-tcp#4: (rcu_read_lock){.+.+..}, at: [<ffffffff815da240>] ip_queue_xmit+0x0/0x680 [ 1614.734997] multipath-tcp#5: (rcu_read_lock_bh){.+....}, at: [<ffffffff815d9925>] ip_finish_output+0x135/0x890 [ 1614.735004] multipath-tcp#6: (rcu_read_lock_bh){.+....}, at: [<ffffffff81595680>] dev_queue_xmit+0x0/0xe00 [ 1614.735012] [ 1614.735012] stack backtrace: [ 1614.735016] Pid: 0, comm: swapper/11 Not tainted 3.6.0-rc3+ #782 [ 1614.735018] Call Trace: [ 1614.735020] <IRQ> [<ffffffff810a50ac>] __lock_acquire+0x144c/0x1b10 [ 1614.735033] [<ffffffff810a334b>] ? check_usage+0x9b/0x4d0 [ 1614.735037] [<ffffffff810a6762>] ? mark_held_locks+0x82/0x130 [ 1614.735042] [<ffffffff810a5df0>] lock_acquire+0x90/0x200 [ 1614.735047] [<ffffffffa0209d72>] ? l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [ 1614.735051] [<ffffffff810a69ad>] ? trace_hardirqs_on+0xd/0x10 [ 1614.735060] [<ffffffff81749b31>] _raw_spin_lock+0x41/0x50 [ 1614.735065] [<ffffffffa0209d72>] ? l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [ 1614.735069] [<ffffffffa0209d72>] l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [ 1614.735075] [<ffffffffa014f7f2>] l2tp_eth_dev_xmit+0x32/0x60 [l2tp_eth] [ 1614.735079] [<ffffffff81595112>] dev_hard_start_xmit+0x502/0xa70 [ 1614.735083] [<ffffffff81594c6e>] ? dev_hard_start_xmit+0x5e/0xa70 [ 1614.735087] [<ffffffff815957c1>] ? dev_queue_xmit+0x141/0xe00 [ 1614.735093] [<ffffffff815b622e>] sch_direct_xmit+0xfe/0x290 [ 1614.735098] [<ffffffff81595865>] dev_queue_xmit+0x1e5/0xe00 [ 1614.735102] [<ffffffff81595680>] ? dev_hard_start_xmit+0xa70/0xa70 [ 1614.735106] [<ffffffff815b4daa>] ? eth_header+0x3a/0xf0 [ 1614.735111] [<ffffffff8161d33e>] ? fib_get_table+0x2e/0x280 [ 1614.735117] [<ffffffff8160a7e2>] arp_xmit+0x22/0x60 [ 1614.735121] [<ffffffff8160a863>] arp_send+0x43/0x50 [ 1614.735125] [<ffffffff8160b82f>] arp_solicit+0x18f/0x450 [ 1614.735132] [<ffffffff8159d9da>] neigh_probe+0x4a/0x70 [ 1614.735137] [<ffffffff815a191a>] __neigh_event_send+0xea/0x300 [ 1614.735141] [<ffffffff815a1c93>] neigh_resolve_output+0x163/0x260 [ 1614.735146] [<ffffffff815d9cf5>] ip_finish_output+0x505/0x890 [ 1614.735150] [<ffffffff815d9925>] ? ip_finish_output+0x135/0x890 [ 1614.735154] [<ffffffff815dae79>] ip_output+0x59/0xf0 [ 1614.735158] [<ffffffff815da1cd>] ip_local_out+0x2d/0xa0 [ 1614.735162] [<ffffffff815da403>] ip_queue_xmit+0x1c3/0x680 [ 1614.735165] [<ffffffff815da240>] ? ip_local_out+0xa0/0xa0 [ 1614.735172] [<ffffffff815f4402>] tcp_transmit_skb+0x402/0xa60 [ 1614.735177] [<ffffffff815f5a11>] tcp_retransmit_skb+0x1a1/0x620 [ 1614.735181] [<ffffffff815f7e93>] tcp_retransmit_timer+0x393/0x960 [ 1614.735185] [<ffffffff815fce23>] ? tcp_v4_err+0x163/0x6b0 [ 1614.735189] [<ffffffff815fd317>] tcp_v4_err+0x657/0x6b0 [ 1614.735194] [<ffffffff8160d116>] ? icmp_socket_deliver+0x46/0x230 [ 1614.735199] [<ffffffff8160d19e>] icmp_socket_deliver+0xce/0x230 [ 1614.735203] [<ffffffff8160d116>] ? icmp_socket_deliver+0x46/0x230 [ 1614.735208] [<ffffffff8160d464>] icmp_unreach+0xe4/0x2c0 [ 1614.735213] [<ffffffff8160e520>] icmp_rcv+0x350/0x4a0 [ 1614.735217] [<ffffffff815d3285>] ip_local_deliver_finish+0x135/0x4e0 [ 1614.735221] [<ffffffff815d319c>] ? ip_local_deliver_finish+0x4c/0x4e0 [ 1614.735225] [<ffffffff815d3ffa>] ip_local_deliver+0x4a/0x90 [ 1614.735229] [<ffffffff815d37b7>] ip_rcv_finish+0x187/0x730 [ 1614.735233] [<ffffffff815d425d>] ip_rcv+0x21d/0x300 [ 1614.735237] [<ffffffff81592a1b>] __netif_receive_skb+0x46b/0xd00 [ 1614.735241] [<ffffffff81592801>] ? __netif_receive_skb+0x251/0xd00 [ 1614.735245] [<ffffffff81593368>] process_backlog+0xb8/0x180 [ 1614.735249] [<ffffffff81593cf9>] net_rx_action+0x159/0x330 [ 1614.735257] [<ffffffff810491f0>] __do_softirq+0xd0/0x3e0 [ 1614.735264] [<ffffffff8109ed24>] ? tick_program_event+0x24/0x30 [ 1614.735270] [<ffffffff8175419c>] call_softirq+0x1c/0x30 [ 1614.735278] [<ffffffff8100425d>] do_softirq+0x8d/0xc0 [ 1614.735282] [<ffffffff8104983e>] irq_exit+0xae/0xe0 [ 1614.735287] [<ffffffff8175494e>] smp_apic_timer_interrupt+0x6e/0x99 [ 1614.735291] [<ffffffff81753a1c>] apic_timer_interrupt+0x6c/0x80 [ 1614.735293] <EOI> [<ffffffff810a14ad>] ? trace_hardirqs_off+0xd/0x10 [ 1614.735306] [<ffffffff81336f85>] ? intel_idle+0xf5/0x150 [ 1614.735310] [<ffffffff81336f7e>] ? intel_idle+0xee/0x150 [ 1614.735317] [<ffffffff814e6ea9>] cpuidle_enter+0x19/0x20 [ 1614.735321] [<ffffffff814e7538>] cpuidle_idle_call+0xa8/0x630 [ 1614.735327] [<ffffffff8100c1ba>] cpu_idle+0x8a/0xe0 [ 1614.735333] [<ffffffff8173762e>] start_secondary+0x220/0x222 Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

It seems we need to provide ability for stacked devices to use specific lock_class_key for sch->busylock We could instead default l2tpeth tx_queue_len to 0 (no qdisc), but a user might use a qdisc anyway. (So same fixes are probably needed on non LLTX stacked drivers) Noticed while stressing L2TPV3 setup : ====================================================== [ INFO: possible circular locking dependency detected ] 3.6.0-rc3+ #788 Not tainted ------------------------------------------------------- netperf/4660 is trying to acquire lock: (l2tpsock){+.-...}, at: [<ffffffffa0208db2>] l2tp_xmit_skb+0x172/0xa50 [l2tp_core] but task is already holding lock: (&(&sch->busylock)->rlock){+.-...}, at: [<ffffffff81596595>] dev_queue_xmit+0xd75/0xe00 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> multipath-tcp#1 (&(&sch->busylock)->rlock){+.-...}: [<ffffffff810a5df0>] lock_acquire+0x90/0x200 [<ffffffff817499fc>] _raw_spin_lock_irqsave+0x4c/0x60 [<ffffffff81074872>] __wake_up+0x32/0x70 [<ffffffff8136d39e>] tty_wakeup+0x3e/0x80 [<ffffffff81378fb3>] pty_write+0x73/0x80 [<ffffffff8136cb4c>] tty_put_char+0x3c/0x40 [<ffffffff813722b2>] process_echoes+0x142/0x330 [<ffffffff813742ab>] n_tty_receive_buf+0x8fb/0x1230 [<ffffffff813777b2>] flush_to_ldisc+0x142/0x1c0 [<ffffffff81062818>] process_one_work+0x198/0x760 [<ffffffff81063236>] worker_thread+0x186/0x4b0 [<ffffffff810694d3>] kthread+0x93/0xa0 [<ffffffff81753e24>] kernel_thread_helper+0x4/0x10 -> #0 (l2tpsock){+.-...}: [<ffffffff810a5288>] __lock_acquire+0x1628/0x1b10 [<ffffffff810a5df0>] lock_acquire+0x90/0x200 [<ffffffff817498c1>] _raw_spin_lock+0x41/0x50 [<ffffffffa0208db2>] l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [<ffffffffa021a802>] l2tp_eth_dev_xmit+0x32/0x60 [l2tp_eth] [<ffffffff815952b2>] dev_hard_start_xmit+0x502/0xa70 [<ffffffff815b63ce>] sch_direct_xmit+0xfe/0x290 [<ffffffff81595a05>] dev_queue_xmit+0x1e5/0xe00 [<ffffffff815d9d60>] ip_finish_output+0x3d0/0x890 [<ffffffff815db019>] ip_output+0x59/0xf0 [<ffffffff815da36d>] ip_local_out+0x2d/0xa0 [<ffffffff815da5a3>] ip_queue_xmit+0x1c3/0x680 [<ffffffff815f4192>] tcp_transmit_skb+0x402/0xa60 [<ffffffff815f4a94>] tcp_write_xmit+0x1f4/0xa30 [<ffffffff815f5300>] tcp_push_one+0x30/0x40 [<ffffffff815e6672>] tcp_sendmsg+0xe82/0x1040 [<ffffffff81614495>] inet_sendmsg+0x125/0x230 [<ffffffff81576cdc>] sock_sendmsg+0xdc/0xf0 [<ffffffff81579ece>] sys_sendto+0xfe/0x130 [<ffffffff81752c92>] system_call_fastpath+0x16/0x1b Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&(&sch->busylock)->rlock); lock(l2tpsock); lock(&(&sch->busylock)->rlock); lock(l2tpsock); *** DEADLOCK *** 5 locks held by netperf/4660: #0: (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff815e581c>] tcp_sendmsg+0x2c/0x1040 multipath-tcp#1: (rcu_read_lock){.+.+..}, at: [<ffffffff815da3e0>] ip_queue_xmit+0x0/0x680 multipath-tcp#2: (rcu_read_lock_bh){.+....}, at: [<ffffffff815d9ac5>] ip_finish_output+0x135/0x890 multipath-tcp#3: (rcu_read_lock_bh){.+....}, at: [<ffffffff81595820>] dev_queue_xmit+0x0/0xe00 multipath-tcp#4: (&(&sch->busylock)->rlock){+.-...}, at: [<ffffffff81596595>] dev_queue_xmit+0xd75/0xe00 stack backtrace: Pid: 4660, comm: netperf Not tainted 3.6.0-rc3+ #788 Call Trace: [<ffffffff8173dbf8>] print_circular_bug+0x1fb/0x20c [<ffffffff810a5288>] __lock_acquire+0x1628/0x1b10 [<ffffffff810a334b>] ? check_usage+0x9b/0x4d0 [<ffffffff810a3f44>] ? __lock_acquire+0x2e4/0x1b10 [<ffffffff810a5df0>] lock_acquire+0x90/0x200 [<ffffffffa0208db2>] ? l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [<ffffffff817498c1>] _raw_spin_lock+0x41/0x50 [<ffffffffa0208db2>] ? l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [<ffffffffa0208db2>] l2tp_xmit_skb+0x172/0xa50 [l2tp_core] [<ffffffffa021a802>] l2tp_eth_dev_xmit+0x32/0x60 [l2tp_eth] [<ffffffff815952b2>] dev_hard_start_xmit+0x502/0xa70 [<ffffffff81594e0e>] ? dev_hard_start_xmit+0x5e/0xa70 [<ffffffff81595961>] ? dev_queue_xmit+0x141/0xe00 [<ffffffff815b63ce>] sch_direct_xmit+0xfe/0x290 [<ffffffff81595a05>] dev_queue_xmit+0x1e5/0xe00 [<ffffffff81595820>] ? dev_hard_start_xmit+0xa70/0xa70 [<ffffffff815d9d60>] ip_finish_output+0x3d0/0x890 [<ffffffff815d9ac5>] ? ip_finish_output+0x135/0x890 [<ffffffff815db019>] ip_output+0x59/0xf0 [<ffffffff815da36d>] ip_local_out+0x2d/0xa0 [<ffffffff815da5a3>] ip_queue_xmit+0x1c3/0x680 [<ffffffff815da3e0>] ? ip_local_out+0xa0/0xa0 [<ffffffff815f4192>] tcp_transmit_skb+0x402/0xa60 [<ffffffff815fa25e>] ? tcp_md5_do_lookup+0x18e/0x1a0 [<ffffffff815f4a94>] tcp_write_xmit+0x1f4/0xa30 [<ffffffff815f5300>] tcp_push_one+0x30/0x40 [<ffffffff815e6672>] tcp_sendmsg+0xe82/0x1040 [<ffffffff81614495>] inet_sendmsg+0x125/0x230 [<ffffffff81614370>] ? inet_create+0x6b0/0x6b0 [<ffffffff8157e6e2>] ? sock_update_classid+0xc2/0x3b0 [<ffffffff8157e750>] ? sock_update_classid+0x130/0x3b0 [<ffffffff81576cdc>] sock_sendmsg+0xdc/0xf0 [<ffffffff81162579>] ? fget_light+0x3f9/0x4f0 [<ffffffff81579ece>] sys_sendto+0xfe/0x130 [<ffffffff810a69ad>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff8174a0b0>] ? _raw_spin_unlock_irq+0x30/0x50 [<ffffffff810757e3>] ? finish_task_switch+0x83/0xf0 [<ffffffff810757a6>] ? finish_task_switch+0x46/0xf0 [<ffffffff81752cb7>] ? sysret_check+0x1b/0x56 [<ffffffff81752c92>] system_call_fastpath+0x16/0x1b Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>

Cancel work of the xfs_sync_worker before teardown of the log in xfs_unmountfs. This prevents occasional crashes on unmount like so: PID: 21602 TASK: ee9df060 CPU: 0 COMMAND: "kworker/0:3" #0 [c5377d28] crash_kexec at c0292c94 multipath-tcp#1 [c5377d80] oops_end at c07090c2 multipath-tcp#2 [c5377d98] no_context at c06f614e multipath-tcp#3 [c5377dbc] __bad_area_nosemaphore at c06f6281 multipath-tcp#4 [c5377df4] bad_area_nosemaphore at c06f629b multipath-tcp#5 [c5377e00] do_page_fault at c070b0cb multipath-tcp#6 [c5377e7c] error_code (via page_fault) at c070892c EAX: f300c6a8 EBX: f300c6a8 ECX: 000000c0 EDX: 000000c0 EBP: c5377ed0 DS: 007b ESI: 00000000 ES: 007b EDI: 00000001 GS: ffffad20 CS: 0060 EIP: c0481ad0 ERR: ffffffff EFLAGS: 00010246 multipath-tcp#7 [c5377eb0] atomic64_read_cx8 at c0481ad0 multipath-tcp#8 [c5377ebc] xlog_assign_tail_lsn_locked at f7cc7c6e [xfs] multipath-tcp#9 [c5377ed4] xfs_trans_ail_delete_bulk at f7ccd520 [xfs] multipath-tcp#10 [c5377f0c] xfs_buf_iodone at f7ccb602 [xfs] multipath-tcp#11 [c5377f24] xfs_buf_do_callbacks at f7cca524 [xfs] multipath-tcp#12 [c5377f30] xfs_buf_iodone_callbacks at f7cca5da [xfs] multipath-tcp#13 [c5377f4c] xfs_buf_iodone_work at f7c718d0 [xfs] multipath-tcp#14 [c5377f58] process_one_work at c024ee4c multipath-tcp#15 [c5377f98] worker_thread at c024f43d multipath-tcp#16 [c5377fbc] kthread at c025326b multipath-tcp#17 [c5377fe8] kernel_thread_helper at c070e834 PID: 26653 TASK: e79143b0 CPU: 3 COMMAND: "umount" #0 [cde0fda0] __schedule at c0706595 multipath-tcp#1 [cde0fe28] schedule at c0706b89 multipath-tcp#2 [cde0fe30] schedule_timeout at c0705600 multipath-tcp#3 [cde0fe94] __down_common at c0706098 multipath-tcp#4 [cde0fec8] __down at c0706122 multipath-tcp#5 [cde0fed0] down at c025936f multipath-tcp#6 [cde0fee0] xfs_buf_lock at f7c7131d [xfs] multipath-tcp#7 [cde0ff00] xfs_freesb at f7cc2236 [xfs] multipath-tcp#8 [cde0ff10] xfs_fs_put_super at f7c80f21 [xfs] multipath-tcp#9 [cde0ff1c] generic_shutdown_super at c0333d7a multipath-tcp#10 [cde0ff38] kill_block_super at c0333e0f multipath-tcp#11 [cde0ff48] deactivate_locked_super at c0334218 multipath-tcp#12 [cde0ff58] deactivate_super at c033495d multipath-tcp#13 [cde0ff68] mntput_no_expire at c034bc13 multipath-tcp#14 [cde0ff7c] sys_umount at c034cc69 multipath-tcp#15 [cde0ffa0] sys_oldumount at c034ccd4 multipath-tcp#16 [cde0ffb0] system_call at c0707e66 commit 11159a0 added this to xfs_log_unmount and needs to be cleaned up at a later date. Signed-off-by: Ben Myers <bpm@sgi.com> Reviewed-by: Dave Chinner <dchinner@redhat.com> Reviewed-by: Mark Tinguely <tinguely@sgi.com>

As specified by ftrace-design.txt, TIF_SYSCALL_TRACEPOINT was added, as well as NR_syscalls in asm/unistd.h. Additionally, __sys_trace was modified to call trace_sys_enter and trace_sys_exit when appropriate. Tests multipath-tcp#2 - multipath-tcp#4 of "perf test" now complete successfully. Signed-off-by: Steven Walter <stevenrwalter@gmail.com> Signed-off-by: Wade Farnsworth <wade_farnsworth@mentor.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

The next step in reducing RCU's grace-period initialization latency on large systems will make this initialization preemptible. Unfortunately, making the grace-period initialization subject to interrupts (let alone preemption) exposes the following race on systems whose rcu_node tree contains more than one node: 1. CPU 31 starts initializing the grace period, including the first leaf rcu_node structures, and is then preempted. 2. CPU 0 refers to the first leaf rcu_node structure, and notes that a new grace period has started. It passes through a quiescent state shortly thereafter, and informs the RCU core of this rite of passage. 3. CPU 0 enters an RCU read-side critical section, acquiring a pointer to an RCU-protected data item. 4. CPU 31 takes an interrupt whose handler removes the data item referenced by CPU 0 from the data structure, and registers an RCU callback in order to free it. 5. CPU 31 resumes initializing the grace period, including its own rcu_node structure. In invokes rcu_start_gp_per_cpu(), which advances all callbacks, including the one registered in multipath-tcp#4 above, to be handled by the current grace period. 6. The remaining CPUs pass through quiescent states and inform the RCU core, but CPU 0 remains in its RCU read-side critical section, still referencing the now-removed data item. 7. The grace period completes and all the callbacks are invoked, including the one that frees the data item that CPU 0 is still referencing. Oops!!! One way to avoid this race is to remove grace-period acceleration from rcu_start_gp_per_cpu(). Now, the only reason for this acceleration was to allow CPUs bringing RCU out of idle state to have their callbacks invoked after only one grace period, rather than the two grace periods that would otherwise be required. But this acceleration does not work when RCU grace-period initialization is moved to a kthread because the CPU posting the callback is no longer necessarily the CPU that is initializing the resulting grace period. This commit therefore removes this now-pointless (and soon to be dangerous) grace-period acceleration, thus avoiding the above race. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>

If a qdisc is installed on a bonding device, its possible to get following lockdep splat under stress : ============================================= [ INFO: possible recursive locking detected ] 3.6.0+ multipath-tcp#211 Not tainted --------------------------------------------- ping/4876 is trying to acquire lock: (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-...}, at: [<ffffffff8157a191>] dev_queue_xmit+0xe1/0x830 but task is already holding lock: (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-...}, at: [<ffffffff8157a191>] dev_queue_xmit+0xe1/0x830 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); lock(dev->qdisc_tx_busylock ?: &qdisc_tx_busylock); *** DEADLOCK *** May be due to missing lock nesting notation 6 locks held by ping/4876: #0: (sk_lock-AF_INET){+.+.+.}, at: [<ffffffff815e5030>] raw_sendmsg+0x600/0xc30 multipath-tcp#1: (rcu_read_lock_bh){.+....}, at: [<ffffffff815ba4bd>] ip_finish_output+0x12d/0x870 multipath-tcp#2: (rcu_read_lock_bh){.+....}, at: [<ffffffff8157a0b0>] dev_queue_xmit+0x0/0x830 multipath-tcp#3: (dev->qdisc_tx_busylock ?: &qdisc_tx_busylock){+.-...}, at: [<ffffffff8157a191>] dev_queue_xmit+0xe1/0x830 multipath-tcp#4: (&bond->lock){++.?..}, at: [<ffffffffa02128c1>] bond_start_xmit+0x31/0x4b0 [bonding] multipath-tcp#5: (rcu_read_lock_bh){.+....}, at: [<ffffffff8157a0b0>] dev_queue_xmit+0x0/0x830 stack backtrace: Pid: 4876, comm: ping Not tainted 3.6.0+ multipath-tcp#211 Call Trace: [<ffffffff810a0145>] __lock_acquire+0x715/0x1b80 [<ffffffff810a256b>] ? mark_held_locks+0x9b/0x100 [<ffffffff810a1bf2>] lock_acquire+0x92/0x1d0 [<ffffffff8157a191>] ? dev_queue_xmit+0xe1/0x830 [<ffffffff81726b7c>] _raw_spin_lock+0x3c/0x50 [<ffffffff8157a191>] ? dev_queue_xmit+0xe1/0x830 [<ffffffff8106264d>] ? rcu_read_lock_bh_held+0x5d/0x90 [<ffffffff8157a191>] dev_queue_xmit+0xe1/0x830 [<ffffffff8157a0b0>] ? netdev_pick_tx+0x570/0x570 [<ffffffffa0212a6a>] bond_start_xmit+0x1da/0x4b0 [bonding] [<ffffffff815796d0>] dev_hard_start_xmit+0x240/0x6b0 [<ffffffff81597c6e>] sch_direct_xmit+0xfe/0x2a0 [<ffffffff8157a249>] dev_queue_xmit+0x199/0x830 [<ffffffff8157a0b0>] ? netdev_pick_tx+0x570/0x570 [<ffffffff815ba96f>] ip_finish_output+0x5df/0x870 [<ffffffff815ba4bd>] ? ip_finish_output+0x12d/0x870 [<ffffffff815bb964>] ip_output+0x54/0xf0 [<ffffffff815bad48>] ip_local_out+0x28/0x90 [<ffffffff815bc444>] ip_send_skb+0x14/0x50 [<ffffffff815bc4b2>] ip_push_pending_frames+0x32/0x40 [<ffffffff815e536a>] raw_sendmsg+0x93a/0xc30 [<ffffffff8128d570>] ? selinux_file_send_sigiotask+0x1f0/0x1f0 [<ffffffff8109ddb4>] ? __lock_is_held+0x54/0x80 [<ffffffff815f6730>] ? inet_recvmsg+0x220/0x220 [<ffffffff8109ddb4>] ? __lock_is_held+0x54/0x80 [<ffffffff815f6855>] inet_sendmsg+0x125/0x240 [<ffffffff815f6730>] ? inet_recvmsg+0x220/0x220 [<ffffffff8155cddb>] sock_sendmsg+0xab/0xe0 [<ffffffff810a1650>] ? lock_release_non_nested+0xa0/0x2e0 [<ffffffff810a1650>] ? lock_release_non_nested+0xa0/0x2e0 [<ffffffff8155d18c>] __sys_sendmsg+0x37c/0x390 [<ffffffff81195b2a>] ? fsnotify+0x2ca/0x7e0 [<ffffffff811958e8>] ? fsnotify+0x88/0x7e0 [<ffffffff81361f36>] ? put_ldisc+0x56/0xd0 [<ffffffff8116f98a>] ? fget_light+0x3da/0x510 [<ffffffff8155f6c4>] sys_sendmsg+0x44/0x80 [<ffffffff8172fc22>] system_call_fastpath+0x16/0x1b Avoid this problem using a distinct lock_class_key for bonding devices. Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Jay Vosburgh <fubar@us.ibm.com> Cc: Andy Gospodarek <andy@greyhouse.net> Signed-off-by: David S. Miller <davem@davemloft.net>

In an effort to get fewer checkpatch reviewer corrections, add a networking specific style test for the preferred networking comment style. /* The preferred style for block comments in * drivers/net/... and net/... is like this */ These tests are only used in net/ and drivers/net/ Tested with: $ cat drivers/net/t.c /* foo */ /* * foo */ /* foo */ /* foo * bar */ $ ./scripts/checkpatch.pl -f drivers/net/t.c WARNING: networking block comments don't use an empty /* line, use /* Comment... multipath-tcp#4: FILE: net/t.c:4: + +/* WARNING: networking block comments put the trailing */ on a separate line multipath-tcp#12: FILE: net/t.c:12: + * bar */ total: 0 errors, 2 warnings, 12 lines checked Signed-off-by: Joe Perches <joe@perches.com> Cc: "Allan, Bruce W" <bruce.w.allan@intel.com> Cc: Andy Whitcroft <apw@canonical.com> Cc: David Miller <davem@davemloft.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

We actually do not do anything about it. Just return a default value of zero and if the kernel tries to write anything but 0 we BUG_ON. This fixes the case when an user tries to suspend the machine and it blows up in save_processor_state b/c 'read_cr8' is set to NULL and we get: kernel BUG at /home/konrad/ssd/linux/arch/x86/include/asm/paravirt.h:100! invalid opcode: 0000 [multipath-tcp#1] SMP Pid: 2687, comm: init.late Tainted: G O 3.6.0upstream-00002-gac264ac-dirty multipath-tcp#4 Bochs Bochs RIP: e030:[<ffffffff814d5f42>] [<ffffffff814d5f42>] save_processor_state+0x212/0x270 .. snip.. Call Trace: [<ffffffff810733bf>] do_suspend_lowlevel+0xf/0xac [<ffffffff8107330c>] ? x86_acpi_suspend_lowlevel+0x10c/0x150 [<ffffffff81342ee2>] acpi_suspend_enter+0x57/0xd5 CC: stable@vger.kernel.org Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

In 32 bit the stack address provided by kernel_stack_pointer() may point to an invalid range causing NULL pointer access or page faults while in NMI (see trace below). This happens if called in softirq context and if the stack is empty. The address at &regs->sp is then out of range. Fixing this by checking if regs and &regs->sp are in the same stack context. Otherwise return the previous stack pointer stored in struct thread_info. If that address is invalid too, return address of regs. BUG: unable to handle kernel NULL pointer dereference at 0000000a IP: [<c1004237>] print_context_stack+0x6e/0x8d *pde = 00000000 Oops: 0000 [multipath-tcp#1] SMP Modules linked in: Pid: 4434, comm: perl Not tainted 3.6.0-rc3-oprofile-i386-standard-g4411a05 multipath-tcp#4 Hewlett-Packard HP xw9400 Workstation/0A1Ch EIP: 0060:[<c1004237>] EFLAGS: 00010093 CPU: 0 EIP is at print_context_stack+0x6e/0x8d EAX: ffffe000 EBX: 0000000a ECX: f4435f94 EDX: 0000000a ESI: f4435f94 EDI: f4435f94 EBP: f5409ec0 ESP: f5409ea0 DS: 007b ES: 007b FS: 00d8 GS: 0033 SS: 0068 CR0: 8005003b CR2: 0000000a CR3: 34ac9000 CR4: 000007d0 DR0: 00000000 DR1: 00000000 DR2: 00000000 DR3: 00000000 DR6: ffff0ff0 DR7: 00000400 Process perl (pid: 4434, ti=f5408000 task=f5637850 task.ti=f4434000) Stack: 000003e8 ffffe000 00001ffc f4e39b00 00000000 0000000a f4435f94 c155198c f5409ef0 c1003723 c155198c f5409f04 00000000 f5409edc 00000000 00000000 f5409ee8 f4435f94 f5409fc4 00000001 f5409f1c c12dce1c 00000000 c155198c Call Trace: [<c1003723>] dump_trace+0x7b/0xa1 [<c12dce1c>] x86_backtrace+0x40/0x88 [<c12db712>] ? oprofile_add_sample+0x56/0x84 [<c12db731>] oprofile_add_sample+0x75/0x84 [<c12ddb5b>] op_amd_check_ctrs+0x46/0x260 [<c12dd40d>] profile_exceptions_notify+0x23/0x4c [<c1395034>] nmi_handle+0x31/0x4a [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13950ed>] do_nmi+0xa0/0x2ff [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c13949e5>] nmi_stack_correct+0x28/0x2d [<c1029dc5>] ? ftrace_define_fields_irq_handler_entry+0x45/0x45 [<c1003603>] ? do_softirq+0x4b/0x7f <IRQ> [<c102a06f>] irq_exit+0x35/0x5b [<c1018f56>] smp_apic_timer_interrupt+0x6c/0x7a [<c1394746>] apic_timer_interrupt+0x2a/0x30 Code: 89 fe eb 08 31 c9 8b 45 0c ff 55 ec 83 c3 04 83 7d 10 00 74 0c 3b 5d 10 73 26 3b 5d e4 73 0c eb 1f 3b 5d f0 76 1a 3b 5d e8 73 15 <8b> 13 89 d0 89 55 e0 e8 ad 42 03 00 85 c0 8b 55 e0 75 a6 eb cc EIP: [<c1004237>] print_context_stack+0x6e/0x8d SS:ESP 0068:f5409ea0 CR2: 000000000000000a ---[ end trace 62afee3481b00012 ]--- Kernel panic - not syncing: Fatal exception in interrupt V2: * add comments to kernel_stack_pointer() * always return a valid stack address by falling back to the address of regs Reported-by: Yang Wei <wei.yang@windriver.com> Cc: <stable@vger.kernel.org> Signed-off-by: Robert Richter <robert.richter@amd.com> Link: http://lkml.kernel.org/r/20120912135059.GZ8285@erda.amd.com Signed-off-by: H. Peter Anvin <hpa@linux.intel.com> Cc: Jun Zhang <jun.zhang@intel.com>

A rescue thread exiting TASK_INTERRUPTIBLE can lead to a task scheduling off, never to be seen again. In the case where this occurred, an exiting thread hit reiserfs homebrew conditional resched while holding a mutex, bringing the box to its knees. PID: 18105 TASK: ffff8807fd412180 CPU: 5 COMMAND: "kdmflush" #0 [ffff8808157e7670] schedule at ffffffff8143f489 multipath-tcp#1 [ffff8808157e77b8] reiserfs_get_block at ffffffffa038ab2d [reiserfs] multipath-tcp#2 [ffff8808157e79a8] __block_write_begin at ffffffff8117fb14 multipath-tcp#3 [ffff8808157e7a98] reiserfs_write_begin at ffffffffa0388695 [reiserfs] multipath-tcp#4 [ffff8808157e7ad8] generic_perform_write at ffffffff810ee9e2 multipath-tcp#5 [ffff8808157e7b58] generic_file_buffered_write at ffffffff810eeb41 multipath-tcp#6 [ffff8808157e7ba8] __generic_file_aio_write at ffffffff810f1a3a multipath-tcp#7 [ffff8808157e7c58] generic_file_aio_write at ffffffff810f1c88 multipath-tcp#8 [ffff8808157e7cc8] do_sync_write at ffffffff8114f850 multipath-tcp#9 [ffff8808157e7dd8] do_acct_process at ffffffff810a268f [exception RIP: kernel_thread_helper] RIP: ffffffff8144a5c0 RSP: ffff8808157e7f58 RFLAGS: 00000202 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000000 RSI: ffffffff8107af60 RDI: ffff8803ee491d18 RBP: 0000000000000000 R8: 0000000000000000 R9: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 Signed-off-by: Mike Galbraith <mgalbraith@suse.de> Signed-off-by: Tejun Heo <tj@kernel.org> Cc: stable@vger.kernel.org

As pointed out by Geert, MC68000 target needs to be disabled when MMU support is enabled. From Geert: This needs a "depends on !MMU". Else allmodconfig will select it, causing -m68000 to be passed to the assembler, which may break the build depending on your version of binutils, a.o. arch/m68k/kernel/entry.S:186: Error: invalid instruction for this architecture; needs 68020 or higher (68020 [68k, 68ec020], 68030 [68ec030], 68040 [68ec040], 68060 [68ec060]) -- statement `bfextu %sp@(50){#0,multipath-tcp#4},%d0' ignored arch/m68k/kernel/entry.S:211: Error: invalid operand mode for this architecture; needs 68020 or higher -- statement `jbsr @(sys_call_table,%d0:l:4)@(0)' ignored Cfr. http://kisskb.ellerman.id.au/kisskb/buildresult/7416877/ Signed-off-by: Luis Alves <ljalvs@gmail.com> Signed-off-by: Greg Ungerer <gerg@uclinux.org>

The offset must be multiplied by 4 to be sure to access the correct 32bit word in the stack scratch space. For instance, a store at scratch memory cell multipath-tcp#1 was generating the following: st r4, [sp, multipath-tcp#1] While the correct code for this is: st r4, [sp, multipath-tcp#4] To reproduce the bug (assuming your system has a NIC with the mac address 52:54:00:12:34:56): echo 0 > /proc/sys/net/core/bpf_jit_enable tcpdump -ni eth0 "ether[1] + ether[2] - ether[3] * ether[4] - ether[5] \ == -0x3AA" # this will capture packets as expected echo 1 > /proc/sys/net/core/bpf_jit_enable tcpdump -ni eth0 "ether[1] + ether[2] - ether[3] * ether[4] - ether[5] \ == -0x3AA" # this will not. This bug was present since the original inclusion of bpf_jit for ARM (ddecdfc: ARM: 7259/3: net: JIT compiler for packet filters). Signed-off-by: Nicolas Schichan <nschichan@freebox.fr> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

Commit 648bb56 ("cgroup: lock cgroup_mutex in cgroup_init_subsys()") made cgroup_init_subsys() grab cgroup_mutex before invoking ->css_alloc() for the root css. Because memcg registers hotcpu notifier from ->css_alloc() for the root css, this introduced circular locking dependency between cgroup_mutex and cpu hotplug. Fix it by moving hotcpu notifier registration to a subsys initcall. ====================================================== [ INFO: possible circular locking dependency detected ] 3.7.0-rc4-work+ multipath-tcp#42 Not tainted ------------------------------------------------------- bash/645 is trying to acquire lock: (cgroup_mutex){+.+.+.}, at: [<ffffffff8110c5b7>] cgroup_lock+0x17/0x20 but task is already holding lock: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8109300f>] cpu_hotplug_begin+0x2f/0x60 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> multipath-tcp#1 (cpu_hotplug.lock){+.+.+.}: lock_acquire+0x97/0x1e0 mutex_lock_nested+0x61/0x3b0 get_online_cpus+0x3c/0x60 rebuild_sched_domains_locked+0x1b/0x70 cpuset_write_resmask+0x298/0x2c0 cgroup_file_write+0x1ef/0x300 vfs_write+0xa8/0x160 sys_write+0x52/0xa0 system_call_fastpath+0x16/0x1b -> #0 (cgroup_mutex){+.+.+.}: __lock_acquire+0x14ce/0x1d20 lock_acquire+0x97/0x1e0 mutex_lock_nested+0x61/0x3b0 cgroup_lock+0x17/0x20 cpuset_handle_hotplug+0x1b/0x560 cpuset_update_active_cpus+0xe/0x10 cpuset_cpu_inactive+0x47/0x50 notifier_call_chain+0x66/0x150 __raw_notifier_call_chain+0xe/0x10 __cpu_notify+0x20/0x40 _cpu_down+0x7e/0x2f0 cpu_down+0x36/0x50 store_online+0x5d/0xe0 dev_attr_store+0x18/0x30 sysfs_write_file+0xe0/0x150 vfs_write+0xa8/0x160 sys_write+0x52/0xa0 system_call_fastpath+0x16/0x1b other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(cpu_hotplug.lock); lock(cgroup_mutex); lock(cpu_hotplug.lock); lock(cgroup_mutex); *** DEADLOCK *** 5 locks held by bash/645: #0: (&buffer->mutex){+.+.+.}, at: [<ffffffff8123bab8>] sysfs_write_file+0x48/0x150 multipath-tcp#1: (s_active#42){.+.+.+}, at: [<ffffffff8123bb38>] sysfs_write_file+0xc8/0x150 multipath-tcp#2: (x86_cpu_hotplug_driver_mutex){+.+...}, at: [<ffffffff81079277>] cpu_hotplug_driver_lock+0x1 +7/0x20 multipath-tcp#3: (cpu_add_remove_lock){+.+.+.}, at: [<ffffffff81093157>] cpu_maps_update_begin+0x17/0x20 multipath-tcp#4: (cpu_hotplug.lock){+.+.+.}, at: [<ffffffff8109300f>] cpu_hotplug_begin+0x2f/0x60 stack backtrace: Pid: 645, comm: bash Not tainted 3.7.0-rc4-work+ multipath-tcp#42 Call Trace: print_circular_bug+0x28e/0x29f __lock_acquire+0x14ce/0x1d20 lock_acquire+0x97/0x1e0 mutex_lock_nested+0x61/0x3b0 cgroup_lock+0x17/0x20 cpuset_handle_hotplug+0x1b/0x560 cpuset_update_active_cpus+0xe/0x10 cpuset_cpu_inactive+0x47/0x50 notifier_call_chain+0x66/0x150 __raw_notifier_call_chain+0xe/0x10 __cpu_notify+0x20/0x40 _cpu_down+0x7e/0x2f0 cpu_down+0x36/0x50 store_online+0x5d/0xe0 dev_attr_store+0x18/0x30 sysfs_write_file+0xe0/0x150 vfs_write+0xa8/0x160 sys_write+0x52/0xa0 system_call_fastpath+0x16/0x1b Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Fengguang Wu <fengguang.wu@intel.com> Acked-by: Michal Hocko <mhocko@suse.cz> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

The new_node_page() is processed as the following procedure. 1. A new node page is allocated. 2. Set PageUptodate with proper footer information. 3. Check if there is a free space for allocation 4.a. If there is no space, f2fs returns with -ENOSPC. 4.b. Otherwise, go next. In the case of step multipath-tcp#4.a, f2fs remains a wrong node page in the page cache with the uptodate flag. Also, even though a new node page is allocated successfully, an error can be occurred afterwards due to allocation failure of the other data structures. In such a case, remove_inode_page() would be triggered, so that we have to clear uptodate flag in truncate_node() too. So, we should remove the uptodate flag, if allocation is failed. Signed-off-by: Jaegeuk Kim <jaegeuk.kim@samsung.com>

Pursuant to this review https://lkml.org/lkml/2012/11/12/500 by Stefan Richter, update the TODO file. - Clarify purpose of TODO file - Remove firewire item multipath-tcp#4. As discussed in this conversation https://lkml.org/lkml/2012/11/13/564 knowing the AR buffer size is not a hard requirement. The required rx buffer size can be determined experimentally. - Remove firewire item multipath-tcp#5. This was a private note for further experimentation. - Change firewire item multipath-tcp#1. Change suggested header from uapi header to kernel-only header. Signed-off-by: Peter Hurley <peter@hurleysoftware.com> Acked-by: Stefan Richter <stefanr@s5r6.in-berlin.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…headers -Top level ARC makefile removes -I for platform headers -asm/irq.h no longer includes plat/irq.h -platform makefile adds -I for it's specfic platform headers -platform code to directly include it's plat/irq.h -Linker script needed plat/memmap.h for CCM info, already in .config Signed-off-by: Vineet Gupta <vgupta@synopsys.com> Cc: Arnd Bergmann <arnd@arndb.de> Acked-by: Arnd Bergmann <arnd@arndb.de>

This fixes an oops where a LAYOUTGET is in still in the rpciod queue, but the requesting processes has been killed. Without this, killing the process does the final pnfs_put_layout_hdr() and sets NFS_I(inode)->layout to NULL while the LAYOUTGET rpc task still references it. Example oops: BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 IP: [<ffffffffa01bd586>] pnfs_choose_layoutget_stateid+0x37/0xef [nfsv4] PGD 7365b067 PUD 7365d067 PMD 0 Oops: 0000 [multipath-tcp#1] SMP DEBUG_PAGEALLOC Modules linked in: nfs_layout_nfsv41_files nfsv4 auth_rpcgss nfs lockd sunrpc ipt_MASQUERADE ip6table_mangle ip6t_REJECT nf_conntrack_ipv6 nf_defrag_ipv6 iptable_nat nf_nat_ipv4 nf_nat iptable_mangle ip6table_filter ip6_tables ppdev e1000 i2c_piix4 i2c_core shpchp parport_pc parport crc32c_intel aesni_intel xts aes_x86_64 lrw gf128mul ablk_helper cryptd mptspi scsi_transport_spi mptscsih mptbase floppy autofs4 CPU 0 Pid: 27, comm: kworker/0:1 Not tainted 3.8.0-dros_cthon2013+ multipath-tcp#4 VMware, Inc. VMware Virtual Platform/440BX Desktop Reference Platform RIP: 0010:[<ffffffffa01bd586>] [<ffffffffa01bd586>] pnfs_choose_layoutget_stateid+0x37/0xef [nfsv4] RSP: 0018:ffff88007b0c1c88 EFLAGS: 00010246 RAX: ffff88006ed36678 RBX: 0000000000000000 RCX: 0000000ea877e3bc RDX: ffff88007a729da8 RSI: 0000000000000000 RDI: ffff88007a72b958 RBP: ffff88007b0c1ca8 R08: 0000000000000002 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: ffff88007a72b958 R13: ffff88007a729da8 R14: 0000000000000000 R15: ffffffffa011077e FS: 0000000000000000(0000) GS:ffff88007f600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000080 CR3: 00000000735f8000 CR4: 00000000001407f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 Process kworker/0:1 (pid: 27, threadinfo ffff88007b0c0000, task ffff88007c2fa0c0) Stack: ffff88006fc05388 ffff88007a72b908 ffff88007b240900 ffff88006fc05388 ffff88007b0c1cd8 ffffffffa01a2170 ffff88007b240900 ffff88007b240900 ffff88007b240970 ffffffffa011077e ffff88007b0c1ce8 ffffffffa0110791 Call Trace: [<ffffffffa01a2170>] nfs4_layoutget_prepare+0x7b/0x92 [nfsv4] [<ffffffffa011077e>] ? __rpc_atrun+0x15/0x15 [sunrpc] [<ffffffffa0110791>] rpc_prepare_task+0x13/0x15 [sunrpc] Reported-by: Tigran Mkrtchyan <tigran.mkrtchyan@desy.de> Signed-off-by: Weston Andros Adamson <dros@netapp.com> Cc: stable@kernel.org Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>

…ernel/git/vgupta/arc Pull new ARC architecture from Vineet Gupta: "Initial ARC Linux port with some fixes on top for 3.9-rc1: I would like to introduce the Linux port to ARC Processors (from Synopsys) for 3.9-rc1. The patch-set has been discussed on the public lists since Nov and has received a fair bit of review, specially from Arnd, tglx, Al and other subsystem maintainers for DeviceTree, kgdb... The arch bits are in arch/arc, some asm-generic changes (acked by Arnd), a minor change to PARISC (acked by Helge). The series is a touch bigger for a new port for 2 main reasons: 1. It enables a basic kernel in first sub-series and adds ptrace/kgdb/.. later 2. Some of the fallout of review (DeviceTree support, multi-platform- image support) were added on top of orig series, primarily to record the revision history. This updated pull request additionally contains - fixes due to our GNU tools catching up with the new syscall/ptrace ABI - some (minor) cross-arch Kconfig updates." * tag 'arc-v3.9-rc1-late' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (82 commits) ARC: split elf.h into uapi and export it for userspace ARC: Fixup the current ABI version ARC: gdbserver using regset interface possibly broken ARC: Kconfig cleanup tracking cross-arch Kconfig pruning in merge window ARC: make a copy of flat DT ARC: [plat-arcfpga] DT arc-uart bindings change: "baud" => "current-speed" ARC: Ensure CONFIG_VIRT_TO_BUS is not enabled ARC: Fix pt_orig_r8 access ARC: [3.9] Fallout of hlist iterator update ARC: 64bit RTSC timestamp hardware issue ARC: Don't fiddle with non-existent caches ARC: Add self to MAINTAINERS ARC: Provide a default serial.h for uart drivers needing BASE_BAUD ARC: [plat-arcfpga] defconfig for fully loaded ARC Linux ARC: [Review] Multi-platform image multipath-tcp#8: platform registers SMP callbacks ARC: [Review] Multi-platform image multipath-tcp#7: SMP common code to use callbacks ARC: [Review] Multi-platform image multipath-tcp#6: cpu-to-dma-addr optional ARC: [Review] Multi-platform image multipath-tcp#5: NR_IRQS defined by ARC core ARC: [Review] Multi-platform image multipath-tcp#4: Isolate platform headers ARC: [Review] Multi-platform image multipath-tcp#3: switch to board callback ...

…optimizations Recent GCC versions (e.g. GCC-4.7.2) perform optimizations based on assumptions about the implementation of memset and similar functions. The current ARM optimized memset code does not return the value of its first argument, as is usually expected from standard implementations. For instance in the following function: void debug_mutex_lock_common(struct mutex *lock, struct mutex_waiter *waiter) { memset(waiter, MUTEX_DEBUG_INIT, sizeof(*waiter)); waiter->magic = waiter; INIT_LIST_HEAD(&waiter->list); } compiled as: 800554d0 <debug_mutex_lock_common>: 800554d0: e92d4008 push {r3, lr} 800554d4: e1a00001 mov r0, r1 800554d8: e3a02010 mov r2, multipath-tcp#16 ; 0x10 800554dc: e3a01011 mov r1, multipath-tcp#17 ; 0x11 800554e0: eb04426e bl 80165ea0 <memset> 800554e4: e1a03000 mov r3, r0 800554e8: e583000c str r0, [r3, multipath-tcp#12] 800554ec: e5830000 str r0, [r3] 800554f0: e5830004 str r0, [r3, multipath-tcp#4] 800554f4: e8bd8008 pop {r3, pc} GCC assumes memset returns the value of pointer 'waiter' in register r0; causing register/memory corruptions. This patch fixes the return value of the assembly version of memset. It adds a 'mov' instruction and merges an additional load+store into existing load/store instructions. For ease of review, here is a breakdown of the patch into 4 simple steps: Step 1 ====== Perform the following substitutions: ip -> r8, then r0 -> ip, and insert 'mov ip, r0' as the first statement of the function. At this point, we have a memset() implementation returning the proper result, but corrupting r8 on some paths (the ones that were using ip). Step 2 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 1: save r8: - str lr, [sp, #-4]! + stmfd sp!, {r8, lr} and restore r8 on both exit paths: - ldmeqfd sp!, {pc} @ Now <64 bytes to go. + ldmeqfd sp!, {r8, pc} @ Now <64 bytes to go. (...) tst r2, multipath-tcp#16 stmneia ip!, {r1, r3, r8, lr} - ldr lr, [sp], multipath-tcp#4 + ldmfd sp!, {r8, lr} Step 3 ====== Make sure r8 is saved and restored when (! CALGN(1)+0) == 0: save r8: - stmfd sp!, {r4-r7, lr} + stmfd sp!, {r4-r8, lr} and restore r8 on both exit paths: bgt 3b - ldmeqfd sp!, {r4-r7, pc} + ldmeqfd sp!, {r4-r8, pc} (...) tst r2, multipath-tcp#16 stmneia ip!, {r4-r7} - ldmfd sp!, {r4-r7, lr} + ldmfd sp!, {r4-r8, lr} Step 4 ====== Rewrite register list "r4-r7, r8" as "r4-r8". Signed-off-by: Ivan Djelic <ivan.djelic@parrot.com> Reviewed-by: Nicolas Pitre <nico@linaro.org> Signed-off-by: Dirk Behme <dirk.behme@gmail.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

[ Upstream commit 1b710b1 ] Sergey didn't like the locking order, uart_port->lock -> tty_port->lock uart_write (uart_port->lock) __uart_start pl011_start_tx pl011_tx_chars uart_write_wakeup tty_port_tty_wakeup tty_port_default tty_port_tty_get (tty_port->lock) but those code is so old, and I have no clue how to de-couple it after checking other locks in the splat. There is an onging effort to make all printk() as deferred, so until that happens, workaround it for now as a short-term fix. LTP: starting iogen01 (export LTPROOT; rwtest -N iogen01 -i 120s -s read,write -Da -Dv -n 2 500b:$TMPDIR/doio.f1.$$ 1000b:$TMPDIR/doio.f2.$$) WARNING: possible circular locking dependency detected ------------------------------------------------------ doio/49441 is trying to acquire lock: ffff008b7cff7290 (&(&zone->lock)->rlock){..-.}, at: rmqueue+0x138/0x2050 but task is already holding lock: 60ff000822352818 (&pool->lock/1){-.-.}, at: start_flush_work+0xd8/0x3f0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&pool->lock/1){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 __queue_work+0x4b4/0xa10 queue_work_on+0xac/0x11c tty_schedule_flip+0x84/0xbc tty_flip_buffer_push+0x1c/0x28 pty_write+0x98/0xd0 n_tty_write+0x450/0x60c tty_write+0x338/0x474 __vfs_write+0x88/0x214 vfs_write+0x12c/0x1a4 redirected_tty_write+0x90/0xdc do_loop_readv_writev+0x140/0x180 do_iter_write+0xe0/0x10c vfs_writev+0x134/0x1cc do_writev+0xbc/0x130 __arm64_sys_writev+0x58/0x8c el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 -> #3 (&(&port->lock)->rlock){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock_irqsave+0x7c/0x9c tty_port_tty_get+0x24/0x60 tty_port_default_wakeup+0x1c/0x3c tty_port_tty_wakeup+0x34/0x40 uart_write_wakeup+0x28/0x44 pl011_tx_chars+0x1b8/0x270 pl011_start_tx+0x24/0x70 __uart_start+0x5c/0x68 uart_write+0x164/0x1c8 do_output_char+0x33c/0x348 n_tty_write+0x4bc/0x60c tty_write+0x338/0x474 redirected_tty_write+0xc0/0xdc do_loop_readv_writev+0x140/0x180 do_iter_write+0xe0/0x10c vfs_writev+0x134/0x1cc do_writev+0xbc/0x130 __arm64_sys_writev+0x58/0x8c el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 -> #2 (&port_lock_key){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 pl011_console_write+0xec/0x2cc console_unlock+0x794/0x96c vprintk_emit+0x260/0x31c vprintk_default+0x54/0x7c vprintk_func+0x218/0x254 printk+0x7c/0xa4 register_console+0x734/0x7b0 uart_add_one_port+0x734/0x834 pl011_register_port+0x6c/0xac sbsa_uart_probe+0x234/0x2ec platform_drv_probe+0xd4/0x124 really_probe+0x250/0x71c driver_probe_device+0xb4/0x200 __device_attach_driver+0xd8/0x188 bus_for_each_drv+0xbc/0x110 __device_attach+0x120/0x220 device_initial_probe+0x20/0x2c bus_probe_device+0x54/0x100 device_add+0xae8/0xc2c platform_device_add+0x278/0x3b8 platform_device_register_full+0x238/0x2ac acpi_create_platform_device+0x2dc/0x3a8 acpi_bus_attach+0x390/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_scan+0x7c/0xb0 acpi_scan_init+0xe4/0x304 acpi_init+0x100/0x114 do_one_initcall+0x348/0x6a0 do_initcall_level+0x190/0x1fc do_basic_setup+0x34/0x4c kernel_init_freeable+0x19c/0x260 kernel_init+0x18/0x338 ret_from_fork+0x10/0x18 -> #1 (console_owner){-...}: lock_acquire+0x320/0x360 console_lock_spinning_enable+0x6c/0x7c console_unlock+0x4f8/0x96c vprintk_emit+0x260/0x31c vprintk_default+0x54/0x7c vprintk_func+0x218/0x254 printk+0x7c/0xa4 get_random_u64+0x1c4/0x1dc shuffle_pick_tail+0x40/0xac __free_one_page+0x424/0x710 free_one_page+0x70/0x120 __free_pages_ok+0x61c/0xa94 __free_pages_core+0x1bc/0x294 memblock_free_pages+0x38/0x48 __free_pages_memory+0xcc/0xfc __free_memory_core+0x70/0x78 free_low_memory_core_early+0x148/0x18c memblock_free_all+0x18/0x54 mem_init+0xb4/0x17c mm_init+0x14/0x38 start_kernel+0x19c/0x530 -> #0 (&(&zone->lock)->rlock){..-.}: validate_chain+0xf6c/0x2e2c __lock_acquire+0x868/0xc2c lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 rmqueue+0x138/0x2050 get_page_from_freelist+0x474/0x688 __alloc_pages_nodemask+0x3b4/0x18dc alloc_pages_current+0xd0/0xe0 alloc_slab_page+0x2b4/0x5e0 new_slab+0xc8/0x6bc ___slab_alloc+0x3b8/0x640 kmem_cache_alloc+0x4b4/0x588 __debug_object_init+0x778/0x8b4 debug_object_init_on_stack+0x40/0x50 start_flush_work+0x16c/0x3f0 __flush_work+0xb8/0x124 flush_work+0x20/0x30 xlog_cil_force_lsn+0x88/0x204 [xfs] xfs_log_force_lsn+0x128/0x1b8 [xfs] xfs_file_fsync+0x3c4/0x488 [xfs] vfs_fsync_range+0xb0/0xd0 generic_write_sync+0x80/0xa0 [xfs] xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs] xfs_file_write_iter+0x1a0/0x218 [xfs] __vfs_write+0x1cc/0x214 vfs_write+0x12c/0x1a4 ksys_write+0xb0/0x120 __arm64_sys_write+0x54/0x88 el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 other info that might help us debug this: Chain exists of: &(&zone->lock)->rlock --> &(&port->lock)->rlock --> &pool->lock/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pool->lock/1); lock(&(&port->lock)->rlock); lock(&pool->lock/1); lock(&(&zone->lock)->rlock); *** DEADLOCK *** 4 locks held by doio/49441: #0: a0ff00886fc27408 (sb_writers#8){.+.+}, at: vfs_write+0x118/0x1a4 #1: 8fff00080810dfe0 (&xfs_nondir_ilock_class){++++}, at: xfs_ilock+0x2a8/0x300 [xfs] #2: ffff9000129f2390 (rcu_read_lock){....}, at: rcu_lock_acquire+0x8/0x38 #3: 60ff000822352818 (&pool->lock/1){-.-.}, at: start_flush_work+0xd8/0x3f0 stack backtrace: CPU: 48 PID: 49441 Comm: doio Tainted: G W Hardware name: HPE Apollo 70 /C01_APACHE_MB , BIOS L50_5.13_1.11 06/18/2019 Call trace: dump_backtrace+0x0/0x248 show_stack+0x20/0x2c dump_stack+0xe8/0x150 print_circular_bug+0x368/0x380 check_noncircular+0x28c/0x294 validate_chain+0xf6c/0x2e2c __lock_acquire+0x868/0xc2c lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 rmqueue+0x138/0x2050 get_page_from_freelist+0x474/0x688 __alloc_pages_nodemask+0x3b4/0x18dc alloc_pages_current+0xd0/0xe0 alloc_slab_page+0x2b4/0x5e0 new_slab+0xc8/0x6bc ___slab_alloc+0x3b8/0x640 kmem_cache_alloc+0x4b4/0x588 __debug_object_init+0x778/0x8b4 debug_object_init_on_stack+0x40/0x50 start_flush_work+0x16c/0x3f0 __flush_work+0xb8/0x124 flush_work+0x20/0x30 xlog_cil_force_lsn+0x88/0x204 [xfs] xfs_log_force_lsn+0x128/0x1b8 [xfs] xfs_file_fsync+0x3c4/0x488 [xfs] vfs_fsync_range+0xb0/0xd0 generic_write_sync+0x80/0xa0 [xfs] xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs] xfs_file_write_iter+0x1a0/0x218 [xfs] __vfs_write+0x1cc/0x214 vfs_write+0x12c/0x1a4 ksys_write+0xb0/0x120 __arm64_sys_write+0x54/0x88 el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/r/1573679785-21068-1-git-send-email-cai@lca.pw Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 1b0e81416a24d6e9b8c2341e22e8bf48f8b8bfc9 ] Commit 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device") assumes the device_is_registered() in function nfc_dev_up() will help to check when the rfkill is unregistered. However, this check only take effect when device_del(&dev->dev) is done in nfc_unregister_device(). Hence, the rfkill object is still possible be dereferenced. The crash trace in latest kernel (5.18-rc2): [ 68.760105] ================================================================== [ 68.760330] BUG: KASAN: use-after-free in __lock_acquire+0x3ec1/0x6750 [ 68.760756] Read of size 8 at addr ffff888009c93018 by task fuzz/313 [ 68.760756] [ 68.760756] CPU: 0 PID: 313 Comm: fuzz Not tainted 5.18.0-rc2 #4 [ 68.760756] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.14.0-0-g155821a1990b-prebuilt.qemu.org 04/01/2014 [ 68.760756] Call Trace: [ 68.760756] <TASK> [ 68.760756] dump_stack_lvl+0x57/0x7d [ 68.760756] print_report.cold+0x5e/0x5db [ 68.760756] ? __lock_acquire+0x3ec1/0x6750 [ 68.760756] kasan_report+0xbe/0x1c0 [ 68.760756] ? __lock_acquire+0x3ec1/0x6750 [ 68.760756] __lock_acquire+0x3ec1/0x6750 [ 68.760756] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 68.760756] ? register_lock_class+0x18d0/0x18d0 [ 68.760756] lock_acquire+0x1ac/0x4f0 [ 68.760756] ? rfkill_blocked+0xe/0x60 [ 68.760756] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 68.760756] ? mutex_lock_io_nested+0x12c0/0x12c0 [ 68.760756] ? nla_get_range_signed+0x540/0x540 [ 68.760756] ? _raw_spin_lock_irqsave+0x4e/0x50 [ 68.760756] _raw_spin_lock_irqsave+0x39/0x50 [ 68.760756] ? rfkill_blocked+0xe/0x60 [ 68.760756] rfkill_blocked+0xe/0x60 [ 68.760756] nfc_dev_up+0x84/0x260 [ 68.760756] nfc_genl_dev_up+0x90/0xe0 [ 68.760756] genl_family_rcv_msg_doit+0x1f4/0x2f0 [ 68.760756] ? genl_family_rcv_msg_attrs_parse.constprop.0+0x230/0x230 [ 68.760756] ? security_capable+0x51/0x90 [ 68.760756] genl_rcv_msg+0x280/0x500 [ 68.760756] ? genl_get_cmd+0x3c0/0x3c0 [ 68.760756] ? lock_acquire+0x1ac/0x4f0 [ 68.760756] ? nfc_genl_dev_down+0xe0/0xe0 [ 68.760756] ? lockdep_hardirqs_on_prepare+0x410/0x410 [ 68.760756] netlink_rcv_skb+0x11b/0x340 [ 68.760756] ? genl_get_cmd+0x3c0/0x3c0 [ 68.760756] ? netlink_ack+0x9c0/0x9c0 [ 68.760756] ? netlink_deliver_tap+0x136/0xb00 [ 68.760756] genl_rcv+0x1f/0x30 [ 68.760756] netlink_unicast+0x430/0x710 [ 68.760756] ? memset+0x20/0x40 [ 68.760756] ? netlink_attachskb+0x740/0x740 [ 68.760756] ? __build_skb_around+0x1f4/0x2a0 [ 68.760756] netlink_sendmsg+0x75d/0xc00 [ 68.760756] ? netlink_unicast+0x710/0x710 [ 68.760756] ? netlink_unicast+0x710/0x710 [ 68.760756] sock_sendmsg+0xdf/0x110 [ 68.760756] __sys_sendto+0x19e/0x270 [ 68.760756] ? __ia32_sys_getpeername+0xa0/0xa0 [ 68.760756] ? fd_install+0x178/0x4c0 [ 68.760756] ? fd_install+0x195/0x4c0 [ 68.760756] ? kernel_fpu_begin_mask+0x1c0/0x1c0 [ 68.760756] __x64_sys_sendto+0xd8/0x1b0 [ 68.760756] ? lockdep_hardirqs_on+0xbf/0x130 [ 68.760756] ? syscall_enter_from_user_mode+0x1d/0x50 [ 68.760756] do_syscall_64+0x3b/0x90 [ 68.760756] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 68.760756] RIP: 0033:0x7f67fb50e6b3 ... [ 68.760756] RSP: 002b:00007f67fa91fe90 EFLAGS: 00000293 ORIG_RAX: 000000000000002c [ 68.760756] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f67fb50e6b3 [ 68.760756] RDX: 000000000000001c RSI: 0000559354603090 RDI: 0000000000000003 [ 68.760756] RBP: 00007f67fa91ff00 R08: 00007f67fa91fedc R09: 000000000000000c [ 68.760756] R10: 0000000000000000 R11: 0000000000000293 R12: 00007ffe824d496e [ 68.760756] R13: 00007ffe824d496f R14: 00007f67fa120000 R15: 0000000000000003 [ 68.760756] </TASK> [ 68.760756] [ 68.760756] Allocated by task 279: [ 68.760756] kasan_save_stack+0x1e/0x40 [ 68.760756] __kasan_kmalloc+0x81/0xa0 [ 68.760756] rfkill_alloc+0x7f/0x280 [ 68.760756] nfc_register_device+0xa3/0x1a0 [ 68.760756] nci_register_device+0x77a/0xad0 [ 68.760756] nfcmrvl_nci_register_dev+0x20b/0x2c0 [ 68.760756] nfcmrvl_nci_uart_open+0xf2/0x1dd [ 68.760756] nci_uart_tty_ioctl+0x2c3/0x4a0 [ 68.760756] tty_ioctl+0x764/0x1310 [ 68.760756] __x64_sys_ioctl+0x122/0x190 [ 68.760756] do_syscall_64+0x3b/0x90 [ 68.760756] entry_SYSCALL_64_after_hwframe+0x44/0xae [ 68.760756] [ 68.760756] Freed by task 314: [ 68.760756] kasan_save_stack+0x1e/0x40 [ 68.760756] kasan_set_track+0x21/0x30 [ 68.760756] kasan_set_free_info+0x20/0x30 [ 68.760756] __kasan_slab_free+0x108/0x170 [ 68.760756] kfree+0xb0/0x330 [ 68.760756] device_release+0x96/0x200 [ 68.760756] kobject_put+0xf9/0x1d0 [ 68.760756] nfc_unregister_device+0x77/0x190 [ 68.760756] nfcmrvl_nci_unregister_dev+0x88/0xd0 [ 68.760756] nci_uart_tty_close+0xdf/0x180 [ 68.760756] tty_ldisc_kill+0x73/0x110 [ 68.760756] tty_ldisc_hangup+0x281/0x5b0 [ 68.760756] __tty_hangup.part.0+0x431/0x890 [ 68.760756] tty_release+0x3a8/0xc80 [ 68.760756] __fput+0x1f0/0x8c0 [ 68.760756] task_work_run+0xc9/0x170 [ 68.760756] exit_to_user_mode_prepare+0x194/0x1a0 [ 68.760756] syscall_exit_to_user_mode+0x19/0x50 [ 68.760756] do_syscall_64+0x48/0x90 [ 68.760756] entry_SYSCALL_64_after_hwframe+0x44/0xae This patch just add the null out of dev->rfkill to make sure such dereference cannot happen. This is safe since the device_lock() already protect the check/write from data race. Fixes: 3e3b5dfcd16a ("NFC: reorder the logic in nfc_{un,}register_device") Signed-off-by: Lin Ma <linma@zju.edu.cn> Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 1b710b1 ] Sergey didn't like the locking order, uart_port->lock -> tty_port->lock uart_write (uart_port->lock) __uart_start pl011_start_tx pl011_tx_chars uart_write_wakeup tty_port_tty_wakeup tty_port_default tty_port_tty_get (tty_port->lock) but those code is so old, and I have no clue how to de-couple it after checking other locks in the splat. There is an onging effort to make all printk() as deferred, so until that happens, workaround it for now as a short-term fix. LTP: starting iogen01 (export LTPROOT; rwtest -N iogen01 -i 120s -s read,write -Da -Dv -n 2 500b:$TMPDIR/doio.f1.$$ 1000b:$TMPDIR/doio.f2.$$) WARNING: possible circular locking dependency detected ------------------------------------------------------ doio/49441 is trying to acquire lock: ffff008b7cff7290 (&(&zone->lock)->rlock){..-.}, at: rmqueue+0x138/0x2050 but task is already holding lock: 60ff000822352818 (&pool->lock/1){-.-.}, at: start_flush_work+0xd8/0x3f0 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #4 (&pool->lock/1){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 __queue_work+0x4b4/0xa10 queue_work_on+0xac/0x11c tty_schedule_flip+0x84/0xbc tty_flip_buffer_push+0x1c/0x28 pty_write+0x98/0xd0 n_tty_write+0x450/0x60c tty_write+0x338/0x474 __vfs_write+0x88/0x214 vfs_write+0x12c/0x1a4 redirected_tty_write+0x90/0xdc do_loop_readv_writev+0x140/0x180 do_iter_write+0xe0/0x10c vfs_writev+0x134/0x1cc do_writev+0xbc/0x130 __arm64_sys_writev+0x58/0x8c el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 -> #3 (&(&port->lock)->rlock){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock_irqsave+0x7c/0x9c tty_port_tty_get+0x24/0x60 tty_port_default_wakeup+0x1c/0x3c tty_port_tty_wakeup+0x34/0x40 uart_write_wakeup+0x28/0x44 pl011_tx_chars+0x1b8/0x270 pl011_start_tx+0x24/0x70 __uart_start+0x5c/0x68 uart_write+0x164/0x1c8 do_output_char+0x33c/0x348 n_tty_write+0x4bc/0x60c tty_write+0x338/0x474 redirected_tty_write+0xc0/0xdc do_loop_readv_writev+0x140/0x180 do_iter_write+0xe0/0x10c vfs_writev+0x134/0x1cc do_writev+0xbc/0x130 __arm64_sys_writev+0x58/0x8c el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 -> #2 (&port_lock_key){-.-.}: lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 pl011_console_write+0xec/0x2cc console_unlock+0x794/0x96c vprintk_emit+0x260/0x31c vprintk_default+0x54/0x7c vprintk_func+0x218/0x254 printk+0x7c/0xa4 register_console+0x734/0x7b0 uart_add_one_port+0x734/0x834 pl011_register_port+0x6c/0xac sbsa_uart_probe+0x234/0x2ec platform_drv_probe+0xd4/0x124 really_probe+0x250/0x71c driver_probe_device+0xb4/0x200 __device_attach_driver+0xd8/0x188 bus_for_each_drv+0xbc/0x110 __device_attach+0x120/0x220 device_initial_probe+0x20/0x2c bus_probe_device+0x54/0x100 device_add+0xae8/0xc2c platform_device_add+0x278/0x3b8 platform_device_register_full+0x238/0x2ac acpi_create_platform_device+0x2dc/0x3a8 acpi_bus_attach+0x390/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_attach+0x108/0x3cc acpi_bus_scan+0x7c/0xb0 acpi_scan_init+0xe4/0x304 acpi_init+0x100/0x114 do_one_initcall+0x348/0x6a0 do_initcall_level+0x190/0x1fc do_basic_setup+0x34/0x4c kernel_init_freeable+0x19c/0x260 kernel_init+0x18/0x338 ret_from_fork+0x10/0x18 -> #1 (console_owner){-...}: lock_acquire+0x320/0x360 console_lock_spinning_enable+0x6c/0x7c console_unlock+0x4f8/0x96c vprintk_emit+0x260/0x31c vprintk_default+0x54/0x7c vprintk_func+0x218/0x254 printk+0x7c/0xa4 get_random_u64+0x1c4/0x1dc shuffle_pick_tail+0x40/0xac __free_one_page+0x424/0x710 free_one_page+0x70/0x120 __free_pages_ok+0x61c/0xa94 __free_pages_core+0x1bc/0x294 memblock_free_pages+0x38/0x48 __free_pages_memory+0xcc/0xfc __free_memory_core+0x70/0x78 free_low_memory_core_early+0x148/0x18c memblock_free_all+0x18/0x54 mem_init+0xb4/0x17c mm_init+0x14/0x38 start_kernel+0x19c/0x530 -> #0 (&(&zone->lock)->rlock){..-.}: validate_chain+0xf6c/0x2e2c __lock_acquire+0x868/0xc2c lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 rmqueue+0x138/0x2050 get_page_from_freelist+0x474/0x688 __alloc_pages_nodemask+0x3b4/0x18dc alloc_pages_current+0xd0/0xe0 alloc_slab_page+0x2b4/0x5e0 new_slab+0xc8/0x6bc ___slab_alloc+0x3b8/0x640 kmem_cache_alloc+0x4b4/0x588 __debug_object_init+0x778/0x8b4 debug_object_init_on_stack+0x40/0x50 start_flush_work+0x16c/0x3f0 __flush_work+0xb8/0x124 flush_work+0x20/0x30 xlog_cil_force_lsn+0x88/0x204 [xfs] xfs_log_force_lsn+0x128/0x1b8 [xfs] xfs_file_fsync+0x3c4/0x488 [xfs] vfs_fsync_range+0xb0/0xd0 generic_write_sync+0x80/0xa0 [xfs] xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs] xfs_file_write_iter+0x1a0/0x218 [xfs] __vfs_write+0x1cc/0x214 vfs_write+0x12c/0x1a4 ksys_write+0xb0/0x120 __arm64_sys_write+0x54/0x88 el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 other info that might help us debug this: Chain exists of: &(&zone->lock)->rlock --> &(&port->lock)->rlock --> &pool->lock/1 Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(&pool->lock/1); lock(&(&port->lock)->rlock); lock(&pool->lock/1); lock(&(&zone->lock)->rlock); *** DEADLOCK *** 4 locks held by doio/49441: #0: a0ff00886fc27408 (sb_writers#8){.+.+}, at: vfs_write+0x118/0x1a4 #1: 8fff00080810dfe0 (&xfs_nondir_ilock_class){++++}, at: xfs_ilock+0x2a8/0x300 [xfs] #2: ffff9000129f2390 (rcu_read_lock){....}, at: rcu_lock_acquire+0x8/0x38 #3: 60ff000822352818 (&pool->lock/1){-.-.}, at: start_flush_work+0xd8/0x3f0 stack backtrace: CPU: 48 PID: 49441 Comm: doio Tainted: G W Hardware name: HPE Apollo 70 /C01_APACHE_MB , BIOS L50_5.13_1.11 06/18/2019 Call trace: dump_backtrace+0x0/0x248 show_stack+0x20/0x2c dump_stack+0xe8/0x150 print_circular_bug+0x368/0x380 check_noncircular+0x28c/0x294 validate_chain+0xf6c/0x2e2c __lock_acquire+0x868/0xc2c lock_acquire+0x320/0x360 _raw_spin_lock+0x64/0x80 rmqueue+0x138/0x2050 get_page_from_freelist+0x474/0x688 __alloc_pages_nodemask+0x3b4/0x18dc alloc_pages_current+0xd0/0xe0 alloc_slab_page+0x2b4/0x5e0 new_slab+0xc8/0x6bc ___slab_alloc+0x3b8/0x640 kmem_cache_alloc+0x4b4/0x588 __debug_object_init+0x778/0x8b4 debug_object_init_on_stack+0x40/0x50 start_flush_work+0x16c/0x3f0 __flush_work+0xb8/0x124 flush_work+0x20/0x30 xlog_cil_force_lsn+0x88/0x204 [xfs] xfs_log_force_lsn+0x128/0x1b8 [xfs] xfs_file_fsync+0x3c4/0x488 [xfs] vfs_fsync_range+0xb0/0xd0 generic_write_sync+0x80/0xa0 [xfs] xfs_file_buffered_aio_write+0x66c/0x6e4 [xfs] xfs_file_write_iter+0x1a0/0x218 [xfs] __vfs_write+0x1cc/0x214 vfs_write+0x12c/0x1a4 ksys_write+0xb0/0x120 __arm64_sys_write+0x54/0x88 el0_svc_handler+0x170/0x240 el0_sync_handler+0x150/0x250 el0_sync+0x164/0x180 Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Signed-off-by: Qian Cai <cai@lca.pw> Link: https://lore.kernel.org/r/1573679785-21068-1-git-send-email-cai@lca.pw Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Sasha Levin <sashal@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…tion commit 07fd5b6cdf3cc30bfde8fe0f644771688be04447 upstream. Each cset (css_set) is pinned by its tasks. When we're moving tasks around across csets for a migration, we need to hold the source and destination csets to ensure that they don't go away while we're moving tasks about. This is done by linking cset->mg_preload_node on either the mgctx->preloaded_src_csets or mgctx->preloaded_dst_csets list. Using the same cset->mg_preload_node for both the src and dst lists was deemed okay as a cset can't be both the source and destination at the same time. Unfortunately, this overloading becomes problematic when multiple tasks are involved in a migration and some of them are identity noop migrations while others are actually moving across cgroups. For example, this can happen with the following sequence on cgroup1: #1> mkdir -p /sys/fs/cgroup/misc/a/b #2> echo $$ > /sys/fs/cgroup/misc/a/cgroup.procs #3> RUN_A_COMMAND_WHICH_CREATES_MULTIPLE_THREADS & #4> PID=$! #5> echo $PID > /sys/fs/cgroup/misc/a/b/tasks #6> echo $PID > /sys/fs/cgroup/misc/a/cgroup.procs the process including the group leader back into a. In this final migration, non-leader threads would be doing identity migration while the group leader is doing an actual one. After #3, let's say the whole process was in cset A, and that after #4, the leader moves to cset B. Then, during #6, the following happens: 1. cgroup_migrate_add_src() is called on B for the leader. 2. cgroup_migrate_add_src() is called on A for the other threads. 3. cgroup_migrate_prepare_dst() is called. It scans the src list. 4. It notices that B wants to migrate to A, so it tries to A to the dst list but realizes that its ->mg_preload_node is already busy. 5. and then it notices A wants to migrate to A as it's an identity migration, it culls it by list_del_init()'ing its ->mg_preload_node and putting references accordingly. 6. The rest of migration takes place with B on the src list but nothing on the dst list. This means that A isn't held while migration is in progress. If all tasks leave A before the migration finishes and the incoming task pins it, the cset will be destroyed leading to use-after-free. This is caused by overloading cset->mg_preload_node for both src and dst preload lists. We wanted to exclude the cset from the src list but ended up inadvertently excluding it from the dst list too. This patch fixes the issue by separating out cset->mg_preload_node into ->mg_src_preload_node and ->mg_dst_preload_node, so that the src and dst preloadings don't interfere with each other. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Mukesh Ojha <quic_mojha@quicinc.com> Reported-by: shisiyuan <shisiyuan19870131@gmail.com> Link: http://lkml.kernel.org/r/1654187688-27411-1-git-send-email-shisiyuan@xiaomi.com Link: https://www.spinics.net/lists/cgroups/msg33313.html Fixes: f817de9 ("cgroup: prepare migration path for unified hierarchy") Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In 2019, Sergey fixed a lockdep splat with 15341b1 ("char/random: silence a lockdep splat with printk()"), but that got reverted soon after from 4.19 because back then it apparently caused various problems. But the issue it was fixing is still there, and more generally, many patches turning printk() into printk_deferred() have landed since, making me suspect it's okay to try this out again. This should fix the following deadlock found by the kernel test robot: [ 18.287691] WARNING: possible circular locking dependency detected [ 18.287692] 4.19.248-00165-g3d1f971aa81f #1 Not tainted [ 18.287693] ------------------------------------------------------ [ 18.287712] stop/202 is trying to acquire lock: [ 18.287713] (ptrval) (console_owner){..-.}, at: console_unlock (??:?) [ 18.287717] [ 18.287718] but task is already holding lock: [ 18.287718] (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?) [ 18.287722] [ 18.287722] which lock already depends on the new lock. [ 18.287723] [ 18.287724] [ 18.287725] the existing dependency chain (in reverse order) is: [ 18.287725] [ 18.287726] -> #2 (&(&port->lock)->rlock){-...}: [ 18.287729] validate_chain+0x84a/0xe00 [ 18.287729] __lock_acquire (lockdep.c:?) [ 18.287730] lock_acquire (??:?) [ 18.287731] _raw_spin_lock_irqsave (??:?) [ 18.287732] tty_port_tty_get (??:?) [ 18.287733] tty_port_default_wakeup (tty_port.c:?) [ 18.287734] tty_port_tty_wakeup (??:?) [ 18.287734] uart_write_wakeup (??:?) [ 18.287735] serial8250_tx_chars (??:?) [ 18.287736] serial8250_handle_irq (??:?) [ 18.287737] serial8250_default_handle_irq (8250_port.c:?) [ 18.287738] serial8250_interrupt (8250_core.c:?) [ 18.287738] __handle_irq_event_percpu (??:?) [ 18.287739] handle_irq_event_percpu (??:?) [ 18.287740] handle_irq_event (??:?) [ 18.287741] handle_edge_irq (??:?) [ 18.287742] handle_irq (??:?) [ 18.287742] do_IRQ (??:?) [ 18.287743] common_interrupt (entry_32.o:?) [ 18.287744] _raw_spin_unlock_irqrestore (??:?) [ 18.287745] uart_write (serial_core.c:?) [ 18.287746] process_output_block (n_tty.c:?) [ 18.287747] n_tty_write (n_tty.c:?) [ 18.287747] tty_write (tty_io.c:?) [ 18.287748] __vfs_write (??:?) [ 18.287749] vfs_write (??:?) [ 18.287750] ksys_write (??:?) [ 18.287750] sys_write (??:?) [ 18.287751] do_fast_syscall_32 (??:?) [ 18.287752] entry_SYSENTER_32 (??:?) [ 18.287752] [ 18.287753] -> #1 (&port_lock_key){-.-.}: [ 18.287756] [ 18.287756] -> #0 (console_owner){..-.}: [ 18.287759] check_prevs_add (lockdep.c:?) [ 18.287760] validate_chain+0x84a/0xe00 [ 18.287761] __lock_acquire (lockdep.c:?) [ 18.287761] lock_acquire (??:?) [ 18.287762] console_unlock (??:?) [ 18.287763] vprintk_emit (??:?) [ 18.287764] vprintk_default (??:?) [ 18.287764] vprintk_func (??:?) [ 18.287765] printk (??:?) [ 18.287766] get_random_u32 (??:?) [ 18.287767] shuffle_freelist (slub.c:?) [ 18.287767] allocate_slab (slub.c:?) [ 18.287768] new_slab (slub.c:?) [ 18.287769] ___slab_alloc+0x6d0/0xb20 [ 18.287770] __slab_alloc+0xd6/0x2e0 [ 18.287770] __kmalloc (??:?) [ 18.287771] tty_buffer_alloc (tty_buffer.c:?) [ 18.287772] __tty_buffer_request_room (tty_buffer.c:?) [ 18.287773] tty_insert_flip_string_fixed_flag (??:?) [ 18.287774] pty_write (pty.c:?) [ 18.287775] process_output_block (n_tty.c:?) [ 18.287776] n_tty_write (n_tty.c:?) [ 18.287777] tty_write (tty_io.c:?) [ 18.287778] __vfs_write (??:?) [ 18.287779] vfs_write (??:?) [ 18.287780] ksys_write (??:?) [ 18.287780] sys_write (??:?) [ 18.287781] do_fast_syscall_32 (??:?) [ 18.287782] entry_SYSENTER_32 (??:?) [ 18.287783] [ 18.287783] other info that might help us debug this: [ 18.287784] [ 18.287785] Chain exists of: [ 18.287785] console_owner --> &port_lock_key --> &(&port->lock)->rlock [ 18.287789] [ 18.287790] Possible unsafe locking scenario: [ 18.287790] [ 18.287791] CPU0 CPU1 [ 18.287792] ---- ---- [ 18.287792] lock(&(&port->lock)->rlock); [ 18.287794] lock(&port_lock_key); [ 18.287814] lock(&(&port->lock)->rlock); [ 18.287815] lock(console_owner); [ 18.287817] [ 18.287818] *** DEADLOCK *** [ 18.287818] [ 18.287819] 6 locks held by stop/202: [ 18.287820] #0: (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read (??:?) [ 18.287823] #1: (ptrval) (&tty->atomic_write_lock){+.+.}, at: tty_write_lock (tty_io.c:?) [ 18.287826] #2: (ptrval) (&o_tty->termios_rwsem/1){++++}, at: n_tty_write (n_tty.c:?) [ 18.287830] #3: (ptrval) (&ldata->output_lock){+.+.}, at: process_output_block (n_tty.c:?) [ 18.287834] #4: (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?) [ 18.287838] #5: (ptrval) (console_lock){+.+.}, at: console_trylock_spinning (printk.c:?) [ 18.287841] [ 18.287842] stack backtrace: [ 18.287843] CPU: 0 PID: 202 Comm: stop Not tainted 4.19.248-00165-g3d1f971aa81f #1 [ 18.287843] Call Trace: [ 18.287844] dump_stack (??:?) [ 18.287845] print_circular_bug.cold+0x78/0x8b [ 18.287846] check_prev_add+0x66a/0xd20 [ 18.287847] check_prevs_add (lockdep.c:?) [ 18.287848] validate_chain+0x84a/0xe00 [ 18.287848] __lock_acquire (lockdep.c:?) [ 18.287849] lock_acquire (??:?) [ 18.287850] ? console_unlock (??:?) [ 18.287851] console_unlock (??:?) [ 18.287851] ? console_unlock (??:?) [ 18.287852] ? native_save_fl (??:?) [ 18.287853] vprintk_emit (??:?) [ 18.287854] vprintk_default (??:?) [ 18.287855] vprintk_func (??:?) [ 18.287855] printk (??:?) [ 18.287856] get_random_u32 (??:?) [ 18.287857] ? shuffle_freelist (slub.c:?) [ 18.287858] shuffle_freelist (slub.c:?) [ 18.287858] ? page_address (??:?) [ 18.287859] allocate_slab (slub.c:?) [ 18.287860] new_slab (slub.c:?) [ 18.287861] ? pvclock_clocksource_read (??:?) [ 18.287862] ___slab_alloc+0x6d0/0xb20 [ 18.287862] ? kvm_sched_clock_read (kvmclock.c:?) [ 18.287863] ? __slab_alloc+0xbc/0x2e0 [ 18.287864] ? native_wbinvd (paravirt.c:?) [ 18.287865] __slab_alloc+0xd6/0x2e0 [ 18.287865] __kmalloc (??:?) [ 18.287866] ? __lock_acquire (lockdep.c:?) [ 18.287867] ? tty_buffer_alloc (tty_buffer.c:?) [ 18.287868] tty_buffer_alloc (tty_buffer.c:?) [ 18.287869] __tty_buffer_request_room (tty_buffer.c:?) [ 18.287869] tty_insert_flip_string_fixed_flag (??:?) [ 18.287870] pty_write (pty.c:?) [ 18.287871] process_output_block (n_tty.c:?) [ 18.287872] n_tty_write (n_tty.c:?) [ 18.287873] ? print_dl_stats (??:?) [ 18.287874] ? n_tty_ioctl (n_tty.c:?) [ 18.287874] tty_write (tty_io.c:?) [ 18.287875] ? n_tty_ioctl (n_tty.c:?) [ 18.287876] ? tty_write_unlock (tty_io.c:?) [ 18.287877] __vfs_write (??:?) [ 18.287877] vfs_write (??:?) [ 18.287878] ? __fget_light (file.c:?) [ 18.287879] ksys_write (??:?) Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Qian Cai <cai@lca.pw> Cc: Lech Perczak <l.perczak@camlintechnologies.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Sasha Levin <sashal@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/lkml/Ytz+lo4zRQYG3JUR@xsang-OptiPlex-9020 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

…tion commit 07fd5b6cdf3cc30bfde8fe0f644771688be04447 upstream. Each cset (css_set) is pinned by its tasks. When we're moving tasks around across csets for a migration, we need to hold the source and destination csets to ensure that they don't go away while we're moving tasks about. This is done by linking cset->mg_preload_node on either the mgctx->preloaded_src_csets or mgctx->preloaded_dst_csets list. Using the same cset->mg_preload_node for both the src and dst lists was deemed okay as a cset can't be both the source and destination at the same time. Unfortunately, this overloading becomes problematic when multiple tasks are involved in a migration and some of them are identity noop migrations while others are actually moving across cgroups. For example, this can happen with the following sequence on cgroup1: #1> mkdir -p /sys/fs/cgroup/misc/a/b #2> echo $$ > /sys/fs/cgroup/misc/a/cgroup.procs #3> RUN_A_COMMAND_WHICH_CREATES_MULTIPLE_THREADS & #4> PID=$! #5> echo $PID > /sys/fs/cgroup/misc/a/b/tasks #6> echo $PID > /sys/fs/cgroup/misc/a/cgroup.procs the process including the group leader back into a. In this final migration, non-leader threads would be doing identity migration while the group leader is doing an actual one. After #3, let's say the whole process was in cset A, and that after #4, the leader moves to cset B. Then, during #6, the following happens: 1. cgroup_migrate_add_src() is called on B for the leader. 2. cgroup_migrate_add_src() is called on A for the other threads. 3. cgroup_migrate_prepare_dst() is called. It scans the src list. 4. It notices that B wants to migrate to A, so it tries to A to the dst list but realizes that its ->mg_preload_node is already busy. 5. and then it notices A wants to migrate to A as it's an identity migration, it culls it by list_del_init()'ing its ->mg_preload_node and putting references accordingly. 6. The rest of migration takes place with B on the src list but nothing on the dst list. This means that A isn't held while migration is in progress. If all tasks leave A before the migration finishes and the incoming task pins it, the cset will be destroyed leading to use-after-free. This is caused by overloading cset->mg_preload_node for both src and dst preload lists. We wanted to exclude the cset from the src list but ended up inadvertently excluding it from the dst list too. This patch fixes the issue by separating out cset->mg_preload_node into ->mg_src_preload_node and ->mg_dst_preload_node, so that the src and dst preloadings don't interfere with each other. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Mukesh Ojha <quic_mojha@quicinc.com> Reported-by: shisiyuan <shisiyuan19870131@gmail.com> Link: http://lkml.kernel.org/r/1654187688-27411-1-git-send-email-shisiyuan@xiaomi.com Link: https://www.spinics.net/lists/cgroups/msg33313.html Fixes: f817de9 ("cgroup: prepare migration path for unified hierarchy") Cc: stable@vger.kernel.org # v3.16+ Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

In 2019, Sergey fixed a lockdep splat with 15341b1 ("char/random: silence a lockdep splat with printk()"), but that got reverted soon after from 4.19 because back then it apparently caused various problems. But the issue it was fixing is still there, and more generally, many patches turning printk() into printk_deferred() have landed since, making me suspect it's okay to try this out again. This should fix the following deadlock found by the kernel test robot: [ 18.287691] WARNING: possible circular locking dependency detected [ 18.287692] 4.19.248-00165-g3d1f971aa81f #1 Not tainted [ 18.287693] ------------------------------------------------------ [ 18.287712] stop/202 is trying to acquire lock: [ 18.287713] (ptrval) (console_owner){..-.}, at: console_unlock (??:?) [ 18.287717] [ 18.287718] but task is already holding lock: [ 18.287718] (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?) [ 18.287722] [ 18.287722] which lock already depends on the new lock. [ 18.287723] [ 18.287724] [ 18.287725] the existing dependency chain (in reverse order) is: [ 18.287725] [ 18.287726] -> #2 (&(&port->lock)->rlock){-...}: [ 18.287729] validate_chain+0x84a/0xe00 [ 18.287729] __lock_acquire (lockdep.c:?) [ 18.287730] lock_acquire (??:?) [ 18.287731] _raw_spin_lock_irqsave (??:?) [ 18.287732] tty_port_tty_get (??:?) [ 18.287733] tty_port_default_wakeup (tty_port.c:?) [ 18.287734] tty_port_tty_wakeup (??:?) [ 18.287734] uart_write_wakeup (??:?) [ 18.287735] serial8250_tx_chars (??:?) [ 18.287736] serial8250_handle_irq (??:?) [ 18.287737] serial8250_default_handle_irq (8250_port.c:?) [ 18.287738] serial8250_interrupt (8250_core.c:?) [ 18.287738] __handle_irq_event_percpu (??:?) [ 18.287739] handle_irq_event_percpu (??:?) [ 18.287740] handle_irq_event (??:?) [ 18.287741] handle_edge_irq (??:?) [ 18.287742] handle_irq (??:?) [ 18.287742] do_IRQ (??:?) [ 18.287743] common_interrupt (entry_32.o:?) [ 18.287744] _raw_spin_unlock_irqrestore (??:?) [ 18.287745] uart_write (serial_core.c:?) [ 18.287746] process_output_block (n_tty.c:?) [ 18.287747] n_tty_write (n_tty.c:?) [ 18.287747] tty_write (tty_io.c:?) [ 18.287748] __vfs_write (??:?) [ 18.287749] vfs_write (??:?) [ 18.287750] ksys_write (??:?) [ 18.287750] sys_write (??:?) [ 18.287751] do_fast_syscall_32 (??:?) [ 18.287752] entry_SYSENTER_32 (??:?) [ 18.287752] [ 18.287753] -> #1 (&port_lock_key){-.-.}: [ 18.287756] [ 18.287756] -> #0 (console_owner){..-.}: [ 18.287759] check_prevs_add (lockdep.c:?) [ 18.287760] validate_chain+0x84a/0xe00 [ 18.287761] __lock_acquire (lockdep.c:?) [ 18.287761] lock_acquire (??:?) [ 18.287762] console_unlock (??:?) [ 18.287763] vprintk_emit (??:?) [ 18.287764] vprintk_default (??:?) [ 18.287764] vprintk_func (??:?) [ 18.287765] printk (??:?) [ 18.287766] get_random_u32 (??:?) [ 18.287767] shuffle_freelist (slub.c:?) [ 18.287767] allocate_slab (slub.c:?) [ 18.287768] new_slab (slub.c:?) [ 18.287769] ___slab_alloc+0x6d0/0xb20 [ 18.287770] __slab_alloc+0xd6/0x2e0 [ 18.287770] __kmalloc (??:?) [ 18.287771] tty_buffer_alloc (tty_buffer.c:?) [ 18.287772] __tty_buffer_request_room (tty_buffer.c:?) [ 18.287773] tty_insert_flip_string_fixed_flag (??:?) [ 18.287774] pty_write (pty.c:?) [ 18.287775] process_output_block (n_tty.c:?) [ 18.287776] n_tty_write (n_tty.c:?) [ 18.287777] tty_write (tty_io.c:?) [ 18.287778] __vfs_write (??:?) [ 18.287779] vfs_write (??:?) [ 18.287780] ksys_write (??:?) [ 18.287780] sys_write (??:?) [ 18.287781] do_fast_syscall_32 (??:?) [ 18.287782] entry_SYSENTER_32 (??:?) [ 18.287783] [ 18.287783] other info that might help us debug this: [ 18.287784] [ 18.287785] Chain exists of: [ 18.287785] console_owner --> &port_lock_key --> &(&port->lock)->rlock [ 18.287789] [ 18.287790] Possible unsafe locking scenario: [ 18.287790] [ 18.287791] CPU0 CPU1 [ 18.287792] ---- ---- [ 18.287792] lock(&(&port->lock)->rlock); [ 18.287794] lock(&port_lock_key); [ 18.287814] lock(&(&port->lock)->rlock); [ 18.287815] lock(console_owner); [ 18.287817] [ 18.287818] *** DEADLOCK *** [ 18.287818] [ 18.287819] 6 locks held by stop/202: [ 18.287820] #0: (ptrval) (&tty->ldisc_sem){++++}, at: ldsem_down_read (??:?) [ 18.287823] #1: (ptrval) (&tty->atomic_write_lock){+.+.}, at: tty_write_lock (tty_io.c:?) [ 18.287826] #2: (ptrval) (&o_tty->termios_rwsem/1){++++}, at: n_tty_write (n_tty.c:?) [ 18.287830] #3: (ptrval) (&ldata->output_lock){+.+.}, at: process_output_block (n_tty.c:?) [ 18.287834] #4: (ptrval) (&(&port->lock)->rlock){-...}, at: pty_write (pty.c:?) [ 18.287838] #5: (ptrval) (console_lock){+.+.}, at: console_trylock_spinning (printk.c:?) [ 18.287841] [ 18.287842] stack backtrace: [ 18.287843] CPU: 0 PID: 202 Comm: stop Not tainted 4.19.248-00165-g3d1f971aa81f #1 [ 18.287843] Call Trace: [ 18.287844] dump_stack (??:?) [ 18.287845] print_circular_bug.cold+0x78/0x8b [ 18.287846] check_prev_add+0x66a/0xd20 [ 18.287847] check_prevs_add (lockdep.c:?) [ 18.287848] validate_chain+0x84a/0xe00 [ 18.287848] __lock_acquire (lockdep.c:?) [ 18.287849] lock_acquire (??:?) [ 18.287850] ? console_unlock (??:?) [ 18.287851] console_unlock (??:?) [ 18.287851] ? console_unlock (??:?) [ 18.287852] ? native_save_fl (??:?) [ 18.287853] vprintk_emit (??:?) [ 18.287854] vprintk_default (??:?) [ 18.287855] vprintk_func (??:?) [ 18.287855] printk (??:?) [ 18.287856] get_random_u32 (??:?) [ 18.287857] ? shuffle_freelist (slub.c:?) [ 18.287858] shuffle_freelist (slub.c:?) [ 18.287858] ? page_address (??:?) [ 18.287859] allocate_slab (slub.c:?) [ 18.287860] new_slab (slub.c:?) [ 18.287861] ? pvclock_clocksource_read (??:?) [ 18.287862] ___slab_alloc+0x6d0/0xb20 [ 18.287862] ? kvm_sched_clock_read (kvmclock.c:?) [ 18.287863] ? __slab_alloc+0xbc/0x2e0 [ 18.287864] ? native_wbinvd (paravirt.c:?) [ 18.287865] __slab_alloc+0xd6/0x2e0 [ 18.287865] __kmalloc (??:?) [ 18.287866] ? __lock_acquire (lockdep.c:?) [ 18.287867] ? tty_buffer_alloc (tty_buffer.c:?) [ 18.287868] tty_buffer_alloc (tty_buffer.c:?) [ 18.287869] __tty_buffer_request_room (tty_buffer.c:?) [ 18.287869] tty_insert_flip_string_fixed_flag (??:?) [ 18.287870] pty_write (pty.c:?) [ 18.287871] process_output_block (n_tty.c:?) [ 18.287872] n_tty_write (n_tty.c:?) [ 18.287873] ? print_dl_stats (??:?) [ 18.287874] ? n_tty_ioctl (n_tty.c:?) [ 18.287874] tty_write (tty_io.c:?) [ 18.287875] ? n_tty_ioctl (n_tty.c:?) [ 18.287876] ? tty_write_unlock (tty_io.c:?) [ 18.287877] __vfs_write (??:?) [ 18.287877] vfs_write (??:?) [ 18.287878] ? __fget_light (file.c:?) [ 18.287879] ksys_write (??:?) Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com> Cc: Qian Cai <cai@lca.pw> Cc: Lech Perczak <l.perczak@camlintechnologies.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Sasha Levin <sashal@kernel.org> Cc: Petr Mladek <pmladek@suse.com> Cc: John Ogness <john.ogness@linutronix.de> Reported-by: kernel test robot <oliver.sang@intel.com> Link: https://lore.kernel.org/lkml/Ytz+lo4zRQYG3JUR@xsang-OptiPlex-9020 Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

commit dc4d31684974d140250f3ee612c3f0cab13b3146 upstream. [BUG] If we have a btrfs image with dirty log, along with an unsupported RO compatible flag: log_root 30474240 ... compat_flags 0x0 compat_ro_flags 0x40000003 ( FREE_SPACE_TREE | FREE_SPACE_TREE_VALID | unknown flag: 0x40000000 ) Then even if we can only mount it RO, we will still cause metadata update for log replay: BTRFS info (device dm-1): flagging fs with big metadata feature BTRFS info (device dm-1): using free space tree BTRFS info (device dm-1): has skinny extents BTRFS info (device dm-1): start tree-log replay This is definitely against RO compact flag requirement. [CAUSE] RO compact flag only forces us to do RO mount, but we will still do log replay for plain RO mount. Thus this will result us to do log replay and update metadata. This can be very problematic for new RO compat flag, for example older kernel can not understand v2 cache, and if we allow metadata update on RO mount and invalidate/corrupt v2 cache. [FIX] Just reject the mount unless rescue=nologreplay is provided: BTRFS error (device dm-1): cannot replay dirty log with unsupport optional features (0x40000000), try rescue=nologreplay instead We don't want to set rescue=nologreply directly, as this would make the end user to read the old data, and cause confusion. Since the such case is really rare, we're mostly fine to just reject the mount with an error message, which also includes the proper workaround. CC: stable@vger.kernel.org multipath-tcp#4.9+ 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>

commit dc4d31684974d140250f3ee612c3f0cab13b3146 upstream. [BUG] If we have a btrfs image with dirty log, along with an unsupported RO compatible flag: log_root 30474240 ... compat_flags 0x0 compat_ro_flags 0x40000003 ( FREE_SPACE_TREE | FREE_SPACE_TREE_VALID | unknown flag: 0x40000000 ) Then even if we can only mount it RO, we will still cause metadata update for log replay: BTRFS info (device dm-1): flagging fs with big metadata feature BTRFS info (device dm-1): using free space tree BTRFS info (device dm-1): has skinny extents BTRFS info (device dm-1): start tree-log replay This is definitely against RO compact flag requirement. [CAUSE] RO compact flag only forces us to do RO mount, but we will still do log replay for plain RO mount. Thus this will result us to do log replay and update metadata. This can be very problematic for new RO compat flag, for example older kernel can not understand v2 cache, and if we allow metadata update on RO mount and invalidate/corrupt v2 cache. [FIX] Just reject the mount unless rescue=nologreplay is provided: BTRFS error (device dm-1): cannot replay dirty log with unsupport optional features (0x40000000), try rescue=nologreplay instead We don't want to set rescue=nologreply directly, as this would make the end user to read the old data, and cause confusion. Since the such case is really rare, we're mostly fine to just reject the mount with an error message, which also includes the proper workaround. CC: stable@vger.kernel.org #4.9+ 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>

[ Upstream commit 84a53580c5d2138c7361c7c3eea5b31827e63b35 ] 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 #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 multipath-tcp#2 0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00, family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775 multipath-tcp#3 genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792 multipath-tcp#4 0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>) at net/netlink/af_netlink.c:2501 multipath-tcp#5 0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803 multipath-tcp#6 0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000) at net/netlink/af_netlink.c:1319 multipath-tcp#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 multipath-tcp#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>

commit 29a5b8a137ac8eb410cc823653a29ac0e7b7e1b0 upstream. When walking through an inode extents, the ext4_ext_binsearch_idx() function assumes that the extent header has been previously validated. However, there are no checks that verify that the number of entries (eh->eh_entries) is non-zero when depth is > 0. And this will lead to problems because the EXT_FIRST_INDEX() and EXT_LAST_INDEX() will return garbage and result in this: [ 135.245946] ------------[ cut here ]------------ [ 135.247579] kernel BUG at fs/ext4/extents.c:2258! [ 135.249045] invalid opcode: 0000 [#1] PREEMPT SMP [ 135.250320] CPU: 2 PID: 238 Comm: tmp118 Not tainted 5.19.0-rc8+ #4 [ 135.252067] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.15.0-0-g2dd4b9b-rebuilt.opensuse.org 04/01/2014 [ 135.255065] RIP: 0010:ext4_ext_map_blocks+0xc20/0xcb0 [ 135.256475] Code: [ 135.261433] RSP: 0018:ffffc900005939f8 EFLAGS: 00010246 [ 135.262847] RAX: 0000000000000024 RBX: ffffc90000593b70 RCX: 0000000000000023 [ 135.264765] RDX: ffff8880038e5f10 RSI: 0000000000000003 RDI: ffff8880046e922c [ 135.266670] RBP: ffff8880046e9348 R08: 0000000000000001 R09: ffff888002ca580c [ 135.268576] R10: 0000000000002602 R11: 0000000000000000 R12: 0000000000000024 [ 135.270477] R13: 0000000000000000 R14: 0000000000000024 R15: 0000000000000000 [ 135.272394] FS: 00007fdabdc56740(0000) GS:ffff88807dd00000(0000) knlGS:0000000000000000 [ 135.274510] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 [ 135.276075] CR2: 00007ffc26bd4f00 CR3: 0000000006261004 CR4: 0000000000170ea0 [ 135.277952] Call Trace: [ 135.278635] <TASK> [ 135.279247] ? preempt_count_add+0x6d/0xa0 [ 135.280358] ? percpu_counter_add_batch+0x55/0xb0 [ 135.281612] ? _raw_read_unlock+0x18/0x30 [ 135.282704] ext4_map_blocks+0x294/0x5a0 [ 135.283745] ? xa_load+0x6f/0xa0 [ 135.284562] ext4_mpage_readpages+0x3d6/0x770 [ 135.285646] read_pages+0x67/0x1d0 [ 135.286492] ? folio_add_lru+0x51/0x80 [ 135.287441] page_cache_ra_unbounded+0x124/0x170 [ 135.288510] filemap_get_pages+0x23d/0x5a0 [ 135.289457] ? path_openat+0xa72/0xdd0 [ 135.290332] filemap_read+0xbf/0x300 [ 135.291158] ? _raw_spin_lock_irqsave+0x17/0x40 [ 135.292192] new_sync_read+0x103/0x170 [ 135.293014] vfs_read+0x15d/0x180 [ 135.293745] ksys_read+0xa1/0xe0 [ 135.294461] do_syscall_64+0x3c/0x80 [ 135.295284] entry_SYSCALL_64_after_hwframe+0x46/0xb0 This patch simply adds an extra check in __ext4_ext_check(), verifying that eh_entries is not 0 when eh_depth is > 0. Link: https://bugzilla.kernel.org/show_bug.cgi?id=215941 Link: https://bugzilla.kernel.org/show_bug.cgi?id=216283 Cc: Baokun Li <libaokun1@huawei.com> Cc: stable@kernel.org Signed-off-by: Luís Henriques <lhenriques@suse.de> Reviewed-by: Jan Kara <jack@suse.cz> Reviewed-by: Baokun Li <libaokun1@huawei.com> Link: https://lore.kernel.org/r/20220822094235.2690-1-lhenriques@suse.de Signed-off-by: Theodore Ts'o <tytso@mit.edu> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 84a53580c5d2138c7361c7c3eea5b31827e63b35 ] 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 #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 #2 0xffffffff81e01435 in genl_family_rcv_msg (extack=0xffffc90000ba7af0, nlh=0xffff88800b1b7600, skb=0xffff88800b1f9f00, family=0xffffffff82fef6c0 <seg6_genl_family>) at net/netlink/genetlink.c:775 #3 genl_rcv_msg (skb=0xffff88800b1f9f00, nlh=0xffff88800b1b7600, extack=0xffffc90000ba7af0) at net/netlink/genetlink.c:792 #4 0xffffffff81dfffc3 in netlink_rcv_skb (skb=skb@entry=0xffff88800b1f9f00, cb=cb@entry=0xffffffff81e01350 <genl_rcv_msg>) at net/netlink/af_netlink.c:2501 #5 0xffffffff81e00919 in genl_rcv (skb=0xffff88800b1f9f00) at net/netlink/genetlink.c:803 #6 0xffffffff81dff6ae in netlink_unicast_kernel (ssk=0xffff888010eec800, skb=0xffff88800b1f9f00, sk=0xffff888004aed000) at net/netlink/af_netlink.c:1319 #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 #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>

…g the sock [ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ] There is a race condition in vxlan that when deleting a vxlan device during receiving packets, there is a possibility that the sock is released after getting vxlan_sock vs from sk_user_data. Then in later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got NULL pointer dereference. e.g. #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757 #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48 #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542 #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62 [exception RIP: vxlan_ecn_decapsulate+0x3b] RIP: ffffffffc1014e7b RSP: ffffa25ec6978cb0 RFLAGS: 00010246 RAX: 0000000000000008 RBX: ffff8aa000888000 RCX: 0000000000000000 RDX: 000000000000000e RSI: ffff8a9fc7ab803e RDI: ffff8a9fd1168700 RBP: ffff8a9fc7ab803e R8: 0000000000700000 R9: 00000000000010ae R10: ffff8a9fcb748980 R11: 0000000000000000 R12: ffff8a9fd1168700 R13: ffff8aa000888000 R14: 00000000002a0000 R15: 00000000000010ae ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan] #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507 #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45 #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807 #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951 #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139 #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3 #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3 Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh Fix this by waiting for all sk_user_data reader to finish before releasing the sock. Reported-by: Jianlin Shi <jishi@redhat.com> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ] Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid but different gss service") introduced `auth` argument to __gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL since it (and auth->service) was not (yet) determined. When multiple upcalls with the same uid and different service are ongoing, it could happen that __gss_find_upcall(), which returns the first match found in the pipe->in_downcall list, could not find the correct gss_msg corresponding to the downcall we are looking for. Moreover, it might return a msg which is not sent to rpc.gssd yet. We could see mount.nfs process hung in D state with multiple mount.nfs are executed in parallel. The call trace below is of CentOS 7.9 kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/ elrepo kernel-ml-6.0.7-1.el7. PID: 71258 TASK: ffff91ebd4be0000 CPU: 36 COMMAND: "mount.nfs" #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss] #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc [sunrpc] #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss] #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc] #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc] #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc] #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc] #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc] The scenario is like this. Let's say there are two upcalls for services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe. When rpc.gssd reads pipe to get the upcall msg corresponding to service B from pipe->pipe and then writes the response, in gss_pipe_downcall the msg corresponding to service A will be picked because only uid is used to find the msg and it is before the one for B in pipe->in_downcall. And the process waiting for the msg corresponding to service A will be woken up. Actual scheduing of that process might be after rpc.gssd processes the next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A). The process is scheduled to see gss_msg->ctx == NULL and gss_msg->msg.errno == 0, therefore it cannot break the loop in gss_create_upcall and is never woken up after that. This patch adds a simple check to ensure that a msg which is not sent to rpc.gssd yet is not chosen as the matching upcall upon receiving a downcall. Signed-off-by: minoura makoto <minoura@valinux.co.jp> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Tested-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

…g the sock [ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ] There is a race condition in vxlan that when deleting a vxlan device during receiving packets, there is a possibility that the sock is released after getting vxlan_sock vs from sk_user_data. Then in later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got NULL pointer dereference. e.g. #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757 #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48 #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542 #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62 [exception RIP: vxlan_ecn_decapsulate+0x3b] RIP: ffffffffc1014e7b RSP: ffffa25ec6978cb0 RFLAGS: 00010246 RAX: 0000000000000008 RBX: ffff8aa000888000 RCX: 0000000000000000 RDX: 000000000000000e RSI: ffff8a9fc7ab803e RDI: ffff8a9fd1168700 RBP: ffff8a9fc7ab803e R8: 0000000000700000 R9: 00000000000010ae R10: ffff8a9fcb748980 R11: 0000000000000000 R12: ffff8a9fd1168700 R13: ffff8aa000888000 R14: 00000000002a0000 R15: 00000000000010ae ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan] #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507 #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45 #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807 #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951 #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139 #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3 #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3 Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh Fix this by waiting for all sk_user_data reader to finish before releasing the sock. Reported-by: Jianlin Shi <jishi@redhat.com> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ] Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid but different gss service") introduced `auth` argument to __gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL since it (and auth->service) was not (yet) determined. When multiple upcalls with the same uid and different service are ongoing, it could happen that __gss_find_upcall(), which returns the first match found in the pipe->in_downcall list, could not find the correct gss_msg corresponding to the downcall we are looking for. Moreover, it might return a msg which is not sent to rpc.gssd yet. We could see mount.nfs process hung in D state with multiple mount.nfs are executed in parallel. The call trace below is of CentOS 7.9 kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/ elrepo kernel-ml-6.0.7-1.el7. PID: 71258 TASK: ffff91ebd4be0000 CPU: 36 COMMAND: "mount.nfs" #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss] #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc [sunrpc] #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss] #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc] #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc] #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc] #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc] #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc] The scenario is like this. Let's say there are two upcalls for services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe. When rpc.gssd reads pipe to get the upcall msg corresponding to service B from pipe->pipe and then writes the response, in gss_pipe_downcall the msg corresponding to service A will be picked because only uid is used to find the msg and it is before the one for B in pipe->in_downcall. And the process waiting for the msg corresponding to service A will be woken up. Actual scheduing of that process might be after rpc.gssd processes the next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A). The process is scheduled to see gss_msg->ctx == NULL and gss_msg->msg.errno == 0, therefore it cannot break the loop in gss_create_upcall and is never woken up after that. This patch adds a simple check to ensure that a msg which is not sent to rpc.gssd yet is not chosen as the matching upcall upon receiving a downcall. Signed-off-by: minoura makoto <minoura@valinux.co.jp> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Tested-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

…g the sock [ Upstream commit 3cf7203ca620682165706f70a1b12b5194607dce ] There is a race condition in vxlan that when deleting a vxlan device during receiving packets, there is a possibility that the sock is released after getting vxlan_sock vs from sk_user_data. Then in later vxlan_ecn_decapsulate(), vxlan_get_sk_family() we will got NULL pointer dereference. e.g. #0 [ffffa25ec6978a38] machine_kexec at ffffffff8c669757 #1 [ffffa25ec6978a90] __crash_kexec at ffffffff8c7c0a4d #2 [ffffa25ec6978b58] crash_kexec at ffffffff8c7c1c48 #3 [ffffa25ec6978b60] oops_end at ffffffff8c627f2b #4 [ffffa25ec6978b80] page_fault_oops at ffffffff8c678fcb #5 [ffffa25ec6978bd8] exc_page_fault at ffffffff8d109542 #6 [ffffa25ec6978c00] asm_exc_page_fault at ffffffff8d200b62 [exception RIP: vxlan_ecn_decapsulate+0x3b] RIP: ffffffffc1014e7b RSP: ffffa25ec6978cb0 RFLAGS: 00010246 RAX: 0000000000000008 RBX: ffff8aa000888000 RCX: 0000000000000000 RDX: 000000000000000e RSI: ffff8a9fc7ab803e RDI: ffff8a9fd1168700 RBP: ffff8a9fc7ab803e R8: 0000000000700000 R9: 00000000000010ae R10: ffff8a9fcb748980 R11: 0000000000000000 R12: ffff8a9fd1168700 R13: ffff8aa000888000 R14: 00000000002a0000 R15: 00000000000010ae ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffa25ec6978ce8] vxlan_rcv at ffffffffc10189cd [vxlan] #8 [ffffa25ec6978d90] udp_queue_rcv_one_skb at ffffffff8cfb6507 #9 [ffffa25ec6978dc0] udp_unicast_rcv_skb at ffffffff8cfb6e45 #10 [ffffa25ec6978dc8] __udp4_lib_rcv at ffffffff8cfb8807 #11 [ffffa25ec6978e20] ip_protocol_deliver_rcu at ffffffff8cf76951 #12 [ffffa25ec6978e48] ip_local_deliver at ffffffff8cf76bde #13 [ffffa25ec6978ea0] __netif_receive_skb_one_core at ffffffff8cecde9b #14 [ffffa25ec6978ec8] process_backlog at ffffffff8cece139 #15 [ffffa25ec6978f00] __napi_poll at ffffffff8ceced1a #16 [ffffa25ec6978f28] net_rx_action at ffffffff8cecf1f3 #17 [ffffa25ec6978fa0] __softirqentry_text_start at ffffffff8d4000ca #18 [ffffa25ec6978ff0] do_softirq at ffffffff8c6fbdc3 Reproducer: https://github.com/Mellanox/ovs-tests/blob/master/test-ovs-vxlan-remove-tunnel-during-traffic.sh Fix this by waiting for all sk_user_data reader to finish before releasing the sock. Reported-by: Jianlin Shi <jishi@redhat.com> Suggested-by: Jakub Sitnicki <jakub@cloudflare.com> Fixes: 6a93cc9 ("udp-tunnel: Add a few more UDP tunnel APIs") Signed-off-by: Hangbin Liu <liuhangbin@gmail.com> Reviewed-by: Jiri Pirko <jiri@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit b18cba09e374637a0a3759d856a6bca94c133952 ] Commit 9130b8d ("SUNRPC: allow for upcalls for the same uid but different gss service") introduced `auth` argument to __gss_find_upcall(), but in gss_pipe_downcall() it was left as NULL since it (and auth->service) was not (yet) determined. When multiple upcalls with the same uid and different service are ongoing, it could happen that __gss_find_upcall(), which returns the first match found in the pipe->in_downcall list, could not find the correct gss_msg corresponding to the downcall we are looking for. Moreover, it might return a msg which is not sent to rpc.gssd yet. We could see mount.nfs process hung in D state with multiple mount.nfs are executed in parallel. The call trace below is of CentOS 7.9 kernel-3.10.0-1160.24.1.el7.x86_64 but we observed the same hang w/ elrepo kernel-ml-6.0.7-1.el7. PID: 71258 TASK: ffff91ebd4be0000 CPU: 36 COMMAND: "mount.nfs" #0 [ffff9203ca3234f8] __schedule at ffffffffa3b8899f #1 [ffff9203ca323580] schedule at ffffffffa3b88eb9 #2 [ffff9203ca323590] gss_cred_init at ffffffffc0355818 [auth_rpcgss] #3 [ffff9203ca323658] rpcauth_lookup_credcache at ffffffffc0421ebc [sunrpc] #4 [ffff9203ca3236d8] gss_lookup_cred at ffffffffc0353633 [auth_rpcgss] #5 [ffff9203ca3236e8] rpcauth_lookupcred at ffffffffc0421581 [sunrpc] #6 [ffff9203ca323740] rpcauth_refreshcred at ffffffffc04223d3 [sunrpc] #7 [ffff9203ca3237a0] call_refresh at ffffffffc04103dc [sunrpc] #8 [ffff9203ca3237b8] __rpc_execute at ffffffffc041e1c9 [sunrpc] #9 [ffff9203ca323820] rpc_execute at ffffffffc0420a48 [sunrpc] The scenario is like this. Let's say there are two upcalls for services A and B, A -> B in pipe->in_downcall, B -> A in pipe->pipe. When rpc.gssd reads pipe to get the upcall msg corresponding to service B from pipe->pipe and then writes the response, in gss_pipe_downcall the msg corresponding to service A will be picked because only uid is used to find the msg and it is before the one for B in pipe->in_downcall. And the process waiting for the msg corresponding to service A will be woken up. Actual scheduing of that process might be after rpc.gssd processes the next msg. In rpc_pipe_generic_upcall it clears msg->errno (for A). The process is scheduled to see gss_msg->ctx == NULL and gss_msg->msg.errno == 0, therefore it cannot break the loop in gss_create_upcall and is never woken up after that. This patch adds a simple check to ensure that a msg which is not sent to rpc.gssd yet is not chosen as the matching upcall upon receiving a downcall. Signed-off-by: minoura makoto <minoura@valinux.co.jp> Signed-off-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Tested-by: Hiroshi Shimamoto <h-shimamoto@nec.com> Cc: Trond Myklebust <trondmy@hammerspace.com> Fixes: 9130b8d ("SUNRPC: allow for upcalls for same uid but different gss service") Signed-off-by: Trond Myklebust <trond.myklebust@hammerspace.com> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 6c4ca03bd890566d873e3593b32d034bf2f5a087 ] During EEH error injection testing, a deadlock was encountered in the tg3 driver when tg3_io_error_detected() was attempting to cancel outstanding reset tasks: crash> foreach UN bt ... PID: 159 TASK: c0000000067c6000 CPU: 8 COMMAND: "eehd" ... #5 [c00000000681f990] __cancel_work_timer at c00000000019fd18 #6 [c00000000681fa30] tg3_io_error_detected at c00800000295f098 [tg3] #7 [c00000000681faf0] eeh_report_error at c00000000004e25c ... PID: 290 TASK: c000000036e5f800 CPU: 6 COMMAND: "kworker/6:1" ... #4 [c00000003721fbc0] rtnl_lock at c000000000c940d8 #5 [c00000003721fbe0] tg3_reset_task at c008000002969358 [tg3] #6 [c00000003721fc60] process_one_work at c00000000019e5c4 ... PID: 296 TASK: c000000037a65800 CPU: 21 COMMAND: "kworker/21:1" ... #4 [c000000037247bc0] rtnl_lock at c000000000c940d8 #5 [c000000037247be0] tg3_reset_task at c008000002969358 [tg3] #6 [c000000037247c60] process_one_work at c00000000019e5c4 ... PID: 655 TASK: c000000036f49000 CPU: 16 COMMAND: "kworker/16:2" ...:1 #4 [c0000000373ebbc0] rtnl_lock at c000000000c940d8 #5 [c0000000373ebbe0] tg3_reset_task at c008000002969358 [tg3] #6 [c0000000373ebc60] process_one_work at c00000000019e5c4 ... Code inspection shows that both tg3_io_error_detected() and tg3_reset_task() attempt to acquire the RTNL lock at the beginning of their code blocks. If tg3_reset_task() should happen to execute between the times when tg3_io_error_deteced() acquires the RTNL lock and tg3_reset_task_cancel() is called, a deadlock will occur. Moving tg3_reset_task_cancel() call earlier within the code block, prior to acquiring RTNL, prevents this from happening, but also exposes another deadlock issue where tg3_reset_task() may execute AFTER tg3_io_error_detected() has executed: crash> foreach UN bt PID: 159 TASK: c0000000067d2000 CPU: 9 COMMAND: "eehd" ... #4 [c000000006867a60] rtnl_lock at c000000000c940d8 #5 [c000000006867a80] tg3_io_slot_reset at c0080000026c2ea8 [tg3] #6 [c000000006867b00] eeh_report_reset at c00000000004de88 ... PID: 363 TASK: c000000037564000 CPU: 6 COMMAND: "kworker/6:1" ... #3 [c000000036c1bb70] msleep at c000000000259e6c #4 [c000000036c1bba0] napi_disable at c000000000c6b848 #5 [c000000036c1bbe0] tg3_reset_task at c0080000026d942c [tg3] #6 [c000000036c1bc60] process_one_work at c00000000019e5c4 ... This issue can be avoided by aborting tg3_reset_task() if EEH error recovery is already in progress. Fixes: db84bf4 ("tg3: tg3_reset_task() needs to use rtnl_lock to synchronize") Signed-off-by: David Christensen <drc@linux.vnet.ibm.com> Reviewed-by: Pavan Chebbi <pavan.chebbi@broadcom.com> Link: https://lore.kernel.org/r/20230124185339.225806-1-drc@linux.vnet.ibm.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

commit 60eed1e3d45045623e46944ebc7c42c30a4350f0 upstream. code path: ocfs2_ioctl_move_extents ocfs2_move_extents ocfs2_defrag_extent __ocfs2_move_extent + ocfs2_journal_access_di + ocfs2_split_extent //sub-paths call jbd2_journal_restart + ocfs2_journal_dirty //crash by jbs2 ASSERT crash stacks: PID: 11297 TASK: ffff974a676dcd00 CPU: 67 COMMAND: "defragfs.ocfs2" #0 [ffffb25d8dad3900] machine_kexec at ffffffff8386fe01 #1 [ffffb25d8dad3958] __crash_kexec at ffffffff8395959d #2 [ffffb25d8dad3a20] crash_kexec at ffffffff8395a45d #3 [ffffb25d8dad3a38] oops_end at ffffffff83836d3f #4 [ffffb25d8dad3a58] do_trap at ffffffff83833205 #5 [ffffb25d8dad3aa0] do_invalid_op at ffffffff83833aa6 #6 [ffffb25d8dad3ac0] invalid_op at ffffffff84200d18 [exception RIP: jbd2_journal_dirty_metadata+0x2ba] RIP: ffffffffc09ca54a RSP: ffffb25d8dad3b70 RFLAGS: 00010207 RAX: 0000000000000000 RBX: ffff9706eedc5248 RCX: 0000000000000000 RDX: 0000000000000001 RSI: ffff97337029ea28 RDI: ffff9706eedc5250 RBP: ffff9703c3520200 R8: 000000000f46b0b2 R9: 0000000000000000 R10: 0000000000000001 R11: 00000001000000fe R12: ffff97337029ea28 R13: 0000000000000000 R14: ffff9703de59bf60 R15: ffff9706eedc5250 ORIG_RAX: ffffffffffffffff CS: 0010 SS: 0018 #7 [ffffb25d8dad3ba8] ocfs2_journal_dirty at ffffffffc137fb95 [ocfs2] #8 [ffffb25d8dad3be8] __ocfs2_move_extent at ffffffffc139a950 [ocfs2] #9 [ffffb25d8dad3c80] ocfs2_defrag_extent at ffffffffc139b2d2 [ocfs2] Analysis This bug has the same root cause of 'commit 7f27ec9 ("ocfs2: call ocfs2_journal_access_di() before ocfs2_journal_dirty() in ocfs2_write_end_nolock()")'. For this bug, jbd2_journal_restart() is called by ocfs2_split_extent() during defragmenting. How to fix For ocfs2_split_extent() can handle journal operations totally by itself. Caller doesn't need to call journal access/dirty pair, and caller only needs to call journal start/stop pair. The fix method is to remove journal access/dirty from __ocfs2_move_extent(). The discussion for this patch: https://oss.oracle.com/pipermail/ocfs2-devel/2023-February/000647.html Link: https://lkml.kernel.org/r/20230217003717.32469-1-heming.zhao@suse.com Signed-off-by: Heming Zhao <heming.zhao@suse.com> Reviewed-by: Joseph Qi <joseph.qi@linux.alibaba.com> Cc: Mark Fasheh <mark@fasheh.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Junxiao Bi <junxiao.bi@oracle.com> Cc: Changwei Ge <gechangwei@live.cn> Cc: Gang He <ghe@suse.com> Cc: Jun Piao <piaojun@huawei.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit da94a7781fc3c92e7df7832bc2746f4d39bc624e ] Error handler of tcf_block_bind() frees the whole bo->cb_list on error. However, by that time the flow_block_cb instances are already in the driver list because driver ndo_setup_tc() callback is called before that up the call chain in tcf_block_offload_cmd(). This leaves dangling pointers to freed objects in the list and causes use-after-free[0]. Fix it by also removing flow_block_cb instances from driver_list before deallocating them. [0]: [ 279.868433] ================================================================== [ 279.869964] BUG: KASAN: slab-use-after-free in flow_block_cb_setup_simple+0x631/0x7c0 [ 279.871527] Read of size 8 at addr ffff888147e2bf20 by task tc/2963 [ 279.873151] CPU: 6 PID: 2963 Comm: tc Not tainted 6.3.0-rc6+ #4 [ 279.874273] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014 [ 279.876295] Call Trace: [ 279.876882] <TASK> [ 279.877413] dump_stack_lvl+0x33/0x50 [ 279.878198] print_report+0xc2/0x610 [ 279.878987] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.879994] kasan_report+0xae/0xe0 [ 279.880750] ? flow_block_cb_setup_simple+0x631/0x7c0 [ 279.881744] ? mlx5e_tc_reoffload_flows_work+0x240/0x240 [mlx5_core] [ 279.883047] flow_block_cb_setup_simple+0x631/0x7c0 [ 279.884027] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.885037] ? tcf_block_setup+0x6b0/0x6b0 [ 279.885901] ? mutex_lock+0x7d/0xd0 [ 279.886669] ? __mutex_unlock_slowpath.constprop.0+0x2d0/0x2d0 [ 279.887844] ? ingress_init+0x1c0/0x1c0 [sch_ingress] [ 279.888846] tcf_block_get_ext+0x61c/0x1200 [ 279.889711] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.890682] ? clsact_init+0x2b0/0x2b0 [sch_ingress] [ 279.891701] qdisc_create+0x401/0xea0 [ 279.892485] ? qdisc_tree_reduce_backlog+0x470/0x470 [ 279.893473] tc_modify_qdisc+0x6f7/0x16d0 [ 279.894344] ? tc_get_qdisc+0xac0/0xac0 [ 279.895213] ? mutex_lock+0x7d/0xd0 [ 279.896005] ? __mutex_lock_slowpath+0x10/0x10 [ 279.896910] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.897770] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.898672] ? __sys_sendmsg+0xb5/0x140 [ 279.899494] ? do_syscall_64+0x3d/0x90 [ 279.900302] ? entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.901337] ? kasan_save_stack+0x2e/0x40 [ 279.902177] ? kasan_save_stack+0x1e/0x40 [ 279.903058] ? kasan_set_track+0x21/0x30 [ 279.903913] ? kasan_save_free_info+0x2a/0x40 [ 279.904836] ? ____kasan_slab_free+0x11a/0x1b0 [ 279.905741] ? kmem_cache_free+0x179/0x400 [ 279.906599] netlink_rcv_skb+0x12c/0x360 [ 279.907450] ? rtnl_calcit.isra.0+0x2b0/0x2b0 [ 279.908360] ? netlink_ack+0x1550/0x1550 [ 279.909192] ? rhashtable_walk_peek+0x170/0x170 [ 279.910135] ? kmem_cache_alloc_node+0x1af/0x390 [ 279.911086] ? _copy_from_iter+0x3d6/0xc70 [ 279.912031] netlink_unicast+0x553/0x790 [ 279.912864] ? netlink_attachskb+0x6a0/0x6a0 [ 279.913763] ? netlink_recvmsg+0x416/0xb50 [ 279.914627] netlink_sendmsg+0x7a1/0xcb0 [ 279.915473] ? netlink_unicast+0x790/0x790 [ 279.916334] ? iovec_from_user.part.0+0x4d/0x220 [ 279.917293] ? netlink_unicast+0x790/0x790 [ 279.918159] sock_sendmsg+0xc5/0x190 [ 279.918938] ____sys_sendmsg+0x535/0x6b0 [ 279.919813] ? import_iovec+0x7/0x10 [ 279.920601] ? kernel_sendmsg+0x30/0x30 [ 279.921423] ? __copy_msghdr+0x3c0/0x3c0 [ 279.922254] ? import_iovec+0x7/0x10 [ 279.923041] ___sys_sendmsg+0xeb/0x170 [ 279.923854] ? copy_msghdr_from_user+0x110/0x110 [ 279.924797] ? ___sys_recvmsg+0xd9/0x130 [ 279.925630] ? __perf_event_task_sched_in+0x183/0x470 [ 279.926656] ? ___sys_sendmsg+0x170/0x170 [ 279.927529] ? ctx_sched_in+0x530/0x530 [ 279.928369] ? update_curr+0x283/0x4f0 [ 279.929185] ? perf_event_update_userpage+0x570/0x570 [ 279.930201] ? __fget_light+0x57/0x520 [ 279.931023] ? __switch_to+0x53d/0xe70 [ 279.931846] ? sockfd_lookup_light+0x1a/0x140 [ 279.932761] __sys_sendmsg+0xb5/0x140 [ 279.933560] ? __sys_sendmsg_sock+0x20/0x20 [ 279.934436] ? fpregs_assert_state_consistent+0x1d/0xa0 [ 279.935490] do_syscall_64+0x3d/0x90 [ 279.936300] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.937311] RIP: 0033:0x7f21c814f887 [ 279.938085] Code: 0a 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10 [ 279.941448] RSP: 002b:00007fff11efd478 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 279.942964] RAX: ffffffffffffffda RBX: 0000000064401979 RCX: 00007f21c814f887 [ 279.944337] RDX: 0000000000000000 RSI: 00007fff11efd4e0 RDI: 0000000000000003 [ 279.945660] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000 [ 279.947003] R10: 00007f21c8008708 R11: 0000000000000246 R12: 0000000000000001 [ 279.948345] R13: 0000000000409980 R14: 000000000047e538 R15: 0000000000485400 [ 279.949690] </TASK> [ 279.950706] Allocated by task 2960: [ 279.951471] kasan_save_stack+0x1e/0x40 [ 279.952338] kasan_set_track+0x21/0x30 [ 279.953165] __kasan_kmalloc+0x77/0x90 [ 279.954006] flow_block_cb_setup_simple+0x3dd/0x7c0 [ 279.955001] tcf_block_offload_cmd.isra.0+0x189/0x2d0 [ 279.956020] tcf_block_get_ext+0x61c/0x1200 [ 279.956881] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.957873] qdisc_create+0x401/0xea0 [ 279.958656] tc_modify_qdisc+0x6f7/0x16d0 [ 279.959506] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.960392] netlink_rcv_skb+0x12c/0x360 [ 279.961216] netlink_unicast+0x553/0x790 [ 279.962044] netlink_sendmsg+0x7a1/0xcb0 [ 279.962906] sock_sendmsg+0xc5/0x190 [ 279.963702] ____sys_sendmsg+0x535/0x6b0 [ 279.964534] ___sys_sendmsg+0xeb/0x170 [ 279.965343] __sys_sendmsg+0xb5/0x140 [ 279.966132] do_syscall_64+0x3d/0x90 [ 279.966908] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.968407] Freed by task 2960: [ 279.969114] kasan_save_stack+0x1e/0x40 [ 279.969929] kasan_set_track+0x21/0x30 [ 279.970729] kasan_save_free_info+0x2a/0x40 [ 279.971603] ____kasan_slab_free+0x11a/0x1b0 [ 279.972483] __kmem_cache_free+0x14d/0x280 [ 279.973337] tcf_block_setup+0x29d/0x6b0 [ 279.974173] tcf_block_offload_cmd.isra.0+0x226/0x2d0 [ 279.975186] tcf_block_get_ext+0x61c/0x1200 [ 279.976080] ingress_init+0x112/0x1c0 [sch_ingress] [ 279.977065] qdisc_create+0x401/0xea0 [ 279.977857] tc_modify_qdisc+0x6f7/0x16d0 [ 279.978695] rtnetlink_rcv_msg+0x5fe/0x9d0 [ 279.979562] netlink_rcv_skb+0x12c/0x360 [ 279.980388] netlink_unicast+0x553/0x790 [ 279.981214] netlink_sendmsg+0x7a1/0xcb0 [ 279.982043] sock_sendmsg+0xc5/0x190 [ 279.982827] ____sys_sendmsg+0x535/0x6b0 [ 279.983703] ___sys_sendmsg+0xeb/0x170 [ 279.984510] __sys_sendmsg+0xb5/0x140 [ 279.985298] do_syscall_64+0x3d/0x90 [ 279.986076] entry_SYSCALL_64_after_hwframe+0x46/0xb0 [ 279.987532] The buggy address belongs to the object at ffff888147e2bf00 which belongs to the cache kmalloc-192 of size 192 [ 279.989747] The buggy address is located 32 bytes inside of freed 192-byte region [ffff888147e2bf00, ffff888147e2bfc0) [ 279.992367] The buggy address belongs to the physical page: [ 279.993430] page:00000000550f405c refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x147e2a [ 279.995182] head:00000000550f405c order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 [ 279.996713] anon flags: 0x200000000010200(slab|head|node=0|zone=2) [ 279.997878] raw: 0200000000010200 ffff888100042a00 0000000000000000 dead000000000001 [ 279.999384] raw: 0000000000000000 0000000000200020 00000001ffffffff 0000000000000000 [ 280.000894] page dumped because: kasan: bad access detected [ 280.002386] Memory state around the buggy address: [ 280.003338] ffff888147e2be00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.004781] ffff888147e2be80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 280.006224] >ffff888147e2bf00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.007700] ^ [ 280.008592] ffff888147e2bf80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc [ 280.010035] ffff888147e2c000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 280.011564] ================================================================== Fixes: 59094b1 ("net: sched: use flow block API") Signed-off-by: Vlad Buslov <vladbu@nvidia.com> Reviewed-by: Simon Horman <simon.horman@corigine.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Sasha Levin <sashal@kernel.org>

[ Upstream commit 05bb0167c80b8f93c6a4e0451b7da9b96db990c2 ] 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 #1.2 0x000020d0f660777f in ubsan_get_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:41 <libclang_rt.asan.so>+0x3d77f #1.1 0x000020d0f660777f in maybe_print_stack_trace() compiler-rt/lib/ubsan/ubsan_diag.cpp:51 <libclang_rt.asan.so>+0x3d77f #1 0x000020d0f660777f in ~scoped_report() compiler-rt/lib/ubsan/ubsan_diag.cpp:387 <libclang_rt.asan.so>+0x3d77f multipath-tcp#2 0x000020d0f660b96d in handlepointer_overflow_impl() compiler-rt/lib/ubsan/ubsan_handlers.cpp:809 <libclang_rt.asan.so>+0x4196d multipath-tcp#3 0x000020d0f660b50d in compiler-rt/lib/ubsan/ubsan_handlers.cpp:815 <libclang_rt.asan.so>+0x4150d multipath-tcp#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 multipath-tcp#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 multipath-tcp#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 multipath-tcp#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 multipath-tcp#8 0x000021e4213aa052 in acpi_ns_evaluate(struct acpi_evaluate_info*) ../../third_party/acpica/source/components/namespace/nseval.c:250 <platform-bus-x86.so>+0x22a052 multipath-tcp#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 multipath-tcp#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 multipath-tcp#11 0x000021e4214131ac in acpi_ns_initialize_devices(u32) ../../third_party/acpica/source/components/namespace/nsinit.c:268 <platform-bus-x86.so>+0x2931ac multipath-tcp#12 0x000021e42147c40d in acpi_initialize_objects(u32) ../../third_party/acpica/source/components/utilities/utxfinit.c:304 <platform-bus-x86.so>+0x2fc40d multipath-tcp#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>

[ Upstream commit 822b5a1c17df7e338b9f05d1cfe5764e37c7f74f ] syzkaller found a data race of pkt_sk(sk)->num. The value is changed under lock_sock() and po->bind_lock, so we need READ_ONCE() to access pkt_sk(sk)->num without these locks in packet_bind_spkt(), packet_bind(), and sk_diag_fill(). Note that WRITE_ONCE() is already added by commit c7d2ef5 ("net/packet: annotate accesses to po->bind"). BUG: KCSAN: data-race in packet_bind / packet_do_bind write (marked) to 0xffff88802ffd1cee of 2 bytes by task 7322 on cpu 0: packet_do_bind+0x446/0x640 net/packet/af_packet.c:3236 packet_bind+0x99/0xe0 net/packet/af_packet.c:3321 __sys_bind+0x19b/0x1e0 net/socket.c:1803 __do_sys_bind net/socket.c:1814 [inline] __se_sys_bind net/socket.c:1812 [inline] __x64_sys_bind+0x40/0x50 net/socket.c:1812 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc read to 0xffff88802ffd1cee of 2 bytes by task 7318 on cpu 1: packet_bind+0xbf/0xe0 net/packet/af_packet.c:3322 __sys_bind+0x19b/0x1e0 net/socket.c:1803 __do_sys_bind net/socket.c:1814 [inline] __se_sys_bind net/socket.c:1812 [inline] __x64_sys_bind+0x40/0x50 net/socket.c:1812 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x72/0xdc value changed: 0x0300 -> 0x0000 Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 7318 Comm: syz-executor.4 Not tainted 6.3.0-13380-g7fddb5b5300c multipath-tcp#4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014 Fixes: 96ec632 ("packet: Diag core and basic socket info dumping") Fixes: 1da177e ("Linux-2.6.12-rc2") Reported-by: syzkaller <syzkaller@googlegroups.com> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20230524232934.50950-1-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>

cpaasch mentioned this issue Sep 2, 2013

WARNING: at /usr/src/mptcp/net/core/dst.c:276 dst_release #15

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limit non-mapping packets in subflow to 64KB #4

limit non-mapping packets in subflow to 64KB #4

cpaasch commented Aug 13, 2013

limit non-mapping packets in subflow to 64KB #4

limit non-mapping packets in subflow to 64KB #4

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cpaasch commented Aug 13, 2013