[syzbot] possible deadlock in _snd_pcm_stream_lock_irqsave (3)

syzbot
2021-11-10T17:00:33Z

Hello,

syzbot found the following issue on:

HEAD commit: cb690f5238d7 Merge tag 'for-5.16/drivers-2021-11-09' of gi..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14db95c1b00000
kernel config: https://syzkaller.appspot.com/x/.config?x=9d7259f0deb293aa
dashboard link: https://syzkaller.appspot.com/bug?extid=58740f570d9b0dacf2a3
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+58740f570d9b0dacf2a3@syzkaller.appspotmail.com

=====================================================
WARNING: SOFTIRQ-safe -> SOFTIRQ-unsafe lock order detected
5.15.0-syzkaller #0 Not tainted
-----------------------------------------------------
syz-executor.3/27804 [HC0[0]:SC0[0]:HE0:SE1] is trying to acquire:
ffff88803102cd38 (&new->fa_lock){....}-{2:2}, at: kill_fasync_rcu fs/fcntl.c:1014 [inline]
ffff88803102cd38 (&new->fa_lock){....}-{2:2}, at: kill_fasync fs/fcntl.c:1035 [inline]
ffff88803102cd38 (&new->fa_lock){....}-{2:2}, at: kill_fasync+0x136/0x470 fs/fcntl.c:1028

and this task is already holding:
ffff88814af73948 (&timer->lock){....}-{2:2}, at: snd_timer_start1+0x5a/0x800 sound/core/timer.c:541
which would create a new lock dependency:
(&timer->lock){....}-{2:2} -> (&new->fa_lock){....}-{2:2}

but this new dependency connects a SOFTIRQ-irq-safe lock:
(&group->lock){..-.}-{2:2}

... which became SOFTIRQ-irq-safe at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
_snd_pcm_stream_lock_irqsave+0x9f/0xd0 sound/core/pcm_native.c:170
snd_pcm_period_elapsed+0x1d/0x50 sound/core/pcm_lib.c:1848
loopback_jiffies_timer_function+0x1c4/0x240 sound/drivers/aloop.c:668
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:636
irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:1002 [inline]
debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1023
slab_free_hook mm/slub.c:1698 [inline]
slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1749
slab_free mm/slub.c:3513 [inline]
kfree+0xf6/0x560 mm/slub.c:4561
skb_free_head net/core/skbuff.c:655 [inline]
skb_release_data+0x65a/0x790 net/core/skbuff.c:677
skb_release_all net/core/skbuff.c:742 [inline]
__kfree_skb net/core/skbuff.c:756 [inline]
kfree_skb net/core/skbuff.c:774 [inline]
kfree_skb+0x133/0x3f0 net/core/skbuff.c:768
ieee80211_iface_work+0x411/0xd00 net/mac80211/iface.c:1522
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

to a SOFTIRQ-irq-unsafe lock:
(tasklist_lock){.+.+}-{2:2}

... which became SOFTIRQ-irq-unsafe at:
...
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228
do_wait+0x284/0xce0 kernel/exit.c:1511
kernel_wait+0x9c/0x150 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

other info that might help us debug this:

Chain exists of:
&group->lock --> &timer->lock --> tasklist_lock

Possible interrupt unsafe locking scenario:

CPU0 CPU1
---- ----
lock(tasklist_lock);
local_irq_disable();
lock(&group->lock);
lock(&timer->lock);
<Interrupt>
lock(&group->lock);

*** DEADLOCK ***

3 locks held by syz-executor.3/27804:
#0: ffff8880409bf568 (&tu->ioctl_lock){+.+.}-{3:3}, at: snd_timer_user_ioctl+0x4c/0xb0 sound/core/timer.c:2128
#1: ffff88814af73948 (&timer->lock){....}-{2:2}, at: snd_timer_start1+0x5a/0x800 sound/core/timer.c:541
#2: ffffffff8b983a20 (rcu_read_lock){....}-{1:2}, at: kill_fasync+0x41/0x470 fs/fcntl.c:1033

the dependencies between SOFTIRQ-irq-safe lock and the holding lock:
-> (&group->lock){..-.}-{2:2} {
IN-SOFTIRQ-W at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
_snd_pcm_stream_lock_irqsave+0x9f/0xd0 sound/core/pcm_native.c:170
snd_pcm_period_elapsed+0x1d/0x50 sound/core/pcm_lib.c:1848
loopback_jiffies_timer_function+0x1c4/0x240 sound/drivers/aloop.c:668
call_timer_fn+0x1a5/0x6b0 kernel/time/timer.c:1421
expire_timers kernel/time/timer.c:1466 [inline]
__run_timers.part.0+0x675/0xa20 kernel/time/timer.c:1734
__run_timers kernel/time/timer.c:1715 [inline]
run_timer_softirq+0xb3/0x1d0 kernel/time/timer.c:1747
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:636
irq_exit_rcu+0x5/0x20 kernel/softirq.c:648
sysvec_apic_timer_interrupt+0x93/0xc0 arch/x86/kernel/apic/apic.c:1097
asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:152 [inline]
_raw_spin_unlock_irqrestore+0x38/0x70 kernel/locking/spinlock.c:194
__debug_check_no_obj_freed lib/debugobjects.c:1002 [inline]
debug_check_no_obj_freed+0x20c/0x420 lib/debugobjects.c:1023
slab_free_hook mm/slub.c:1698 [inline]
slab_free_freelist_hook+0xeb/0x1c0 mm/slub.c:1749
slab_free mm/slub.c:3513 [inline]
kfree+0xf6/0x560 mm/slub.c:4561
skb_free_head net/core/skbuff.c:655 [inline]
skb_release_data+0x65a/0x790 net/core/skbuff.c:677
skb_release_all net/core/skbuff.c:742 [inline]
__kfree_skb net/core/skbuff.c:756 [inline]
kfree_skb net/core/skbuff.c:774 [inline]
kfree_skb+0x133/0x3f0 net/core/skbuff.c:768
ieee80211_iface_work+0x411/0xd00 net/mac80211/iface.c:1522
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INITIAL USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
snd_pcm_group_lock_irq sound/core/pcm_native.c:97 [inline]
snd_pcm_stream_lock_irq sound/core/pcm_native.c:136 [inline]
snd_pcm_hw_params+0x12a/0x1990 sound/core/pcm_native.c:686
snd_pcm_kernel_ioctl+0x164/0x310 sound/core/pcm_native.c:3372
snd_pcm_oss_change_params_locked+0x1936/0x3a60 sound/core/oss/pcm_oss.c:947
snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1091 [inline]
snd_pcm_oss_get_active_substream+0x164/0x1c0 sound/core/oss/pcm_oss.c:1108
snd_pcm_oss_get_formats+0x75/0x340 sound/core/oss/pcm_oss.c:1830
snd_pcm_oss_set_format sound/core/oss/pcm_oss.c:1872 [inline]
snd_pcm_oss_ioctl+0x1034/0x3430 sound/core/oss/pcm_oss.c:2644
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90606fe0>] __key.9+0x0/0x40
-> (&timer->lock){....}-{2:2} {
INITIAL USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
_raw_spin_lock_irq+0x32/0x50 kernel/locking/spinlock.c:170
spin_lock_irq include/linux/spinlock.h:374 [inline]
snd_timer_close_locked+0x63/0xbb0 sound/core/timer.c:396
snd_timer_close+0x87/0xf0 sound/core/timer.c:463
snd_seq_timer_close+0x8c/0xe0 sound/core/seq/seq_timer.c:326
queue_delete+0x4a/0xa0 sound/core/seq/seq_queue.c:134
snd_seq_queue_delete+0x45/0x60 sound/core/seq/seq_queue.c:196
snd_seq_kernel_client_ctl+0x102/0x1e0 sound/core/seq/seq_clientmgr.c:2369
delete_seq_queue.part.0.isra.0+0xa2/0x110 sound/core/seq/oss/seq_oss_init.c:377
delete_seq_queue sound/core/seq/oss/seq_oss_init.c:373 [inline]
snd_seq_oss_release+0x10b/0x1a0 sound/core/seq/oss/seq_oss_init.c:422
odev_release+0x4f/0x70 sound/core/seq/oss/seq_oss.c:144
__fput+0x286/0x9f0 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90606780>] __key.12+0x0/0x40
... acquired at:
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
_raw_spin_lock_irqsave+0x39/0x50 kernel/locking/spinlock.c:162
snd_timer_notify sound/core/timer.c:1087 [inline]
snd_timer_notify+0x10c/0x3d0 sound/core/timer.c:1074
snd_pcm_timer_notify sound/core/pcm_native.c:595 [inline]
snd_pcm_post_start+0x24a/0x310 sound/core/pcm_native.c:1392
snd_pcm_action_single sound/core/pcm_native.c:1229 [inline]
snd_pcm_action+0x143/0x170 sound/core/pcm_native.c:1310
__snd_pcm_lib_xfer+0x1633/0x1d80 sound/core/pcm_lib.c:2221
snd_pcm_oss_read3+0x1c4/0x400 sound/core/oss/pcm_oss.c:1267
snd_pcm_oss_read2+0x300/0x3f0 sound/core/oss/pcm_oss.c:1478
snd_pcm_oss_read1 sound/core/oss/pcm_oss.c:1525 [inline]
snd_pcm_oss_read+0x626/0x7b0 sound/core/oss/pcm_oss.c:2769
vfs_read+0x1b5/0x600 fs/read_write.c:479
ksys_read+0x12d/0x250 fs/read_write.c:619
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

the dependencies between the lock to be acquired
and SOFTIRQ-irq-unsafe lock:
-> (tasklist_lock){.+.+}-{2:2} {
HARDIRQ-ON-R at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228
do_wait+0x284/0xce0 kernel/exit.c:1511
kernel_wait+0x9c/0x150 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
SOFTIRQ-ON-R at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228
do_wait+0x284/0xce0 kernel/exit.c:1511
kernel_wait+0x9c/0x150 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
INITIAL USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316
copy_process+0x36c0/0x75a0 kernel/fork.c:2310
kernel_clone+0xe7/0xab0 kernel/fork.c:2581
kernel_thread+0xb5/0xf0 kernel/fork.c:2633
rest_init+0x23/0x3e0 init/main.c:690
start_kernel+0x47a/0x49b init/main.c:1135
secondary_startup_64_no_verify+0xb0/0xbb
INITIAL READ USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228
do_wait+0x284/0xce0 kernel/exit.c:1511
kernel_wait+0x9c/0x150 kernel/exit.c:1701
call_usermodehelper_exec_sync kernel/umh.c:139 [inline]
call_usermodehelper_exec_work+0xf5/0x180 kernel/umh.c:166
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
kthread+0x405/0x4f0 kernel/kthread.c:327
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
}
... key at: [<ffffffff8b60a098>] tasklist_lock+0x18/0x40
... acquired at:
__raw_read_lock include/linux/rwlock_api_smp.h:149 [inline]
_raw_read_lock+0x5b/0x70 kernel/locking/spinlock.c:228
send_sigio+0xab/0x380 fs/fcntl.c:810
kill_fasync_rcu fs/fcntl.c:1021 [inline]
kill_fasync fs/fcntl.c:1035 [inline]
kill_fasync+0x1f8/0x470 fs/fcntl.c:1028
sock_wake_async+0xd2/0x160 net/socket.c:1368
sk_wake_async include/net/sock.h:2400 [inline]
sk_wake_async include/net/sock.h:2396 [inline]
sock_def_readable+0x349/0x4e0 net/core/sock.c:3138
unix_dgram_sendmsg+0xfa7/0x1950 net/unix/af_unix.c:1941
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
____sys_sendmsg+0x331/0x810 net/socket.c:2409
___sys_sendmsg+0xf3/0x170 net/socket.c:2463
__sys_sendmmsg+0x195/0x470 net/socket.c:2549
__do_sys_sendmmsg net/socket.c:2578 [inline]
__se_sys_sendmmsg net/socket.c:2575 [inline]
__x64_sys_sendmmsg+0x99/0x100 net/socket.c:2575
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> (&f->f_owner.lock){....}-{2:2} {
INITIAL USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316
f_modown+0x2a/0x390 fs/fcntl.c:91
__f_setown fs/fcntl.c:110 [inline]
f_setown+0xd7/0x230 fs/fcntl.c:138
do_fcntl+0x749/0x1210 fs/fcntl.c:393
__do_sys_fcntl fs/fcntl.c:472 [inline]
__se_sys_fcntl fs/fcntl.c:457 [inline]
__x64_sys_fcntl+0x165/0x1e0 fs/fcntl.c:457
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
INITIAL READ USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock_irq include/linux/rwlock_api_smp.h:168 [inline]
_raw_read_lock_irq+0x63/0x80 kernel/locking/spinlock.c:244
f_getown+0x23/0x2a0 fs/fcntl.c:154
do_fcntl+0xbd8/0x1210 fs/fcntl.c:389
__do_sys_fcntl fs/fcntl.c:472 [inline]
__se_sys_fcntl fs/fcntl.c:457 [inline]
__x64_sys_fcntl+0x165/0x1e0 fs/fcntl.c:457
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90307de0>] __key.5+0x0/0x40
... acquired at:
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236
send_sigio+0x24/0x380 fs/fcntl.c:796
kill_fasync_rcu fs/fcntl.c:1021 [inline]
kill_fasync fs/fcntl.c:1035 [inline]
kill_fasync+0x1f8/0x470 fs/fcntl.c:1028
sock_wake_async+0xd2/0x160 net/socket.c:1368
sk_wake_async include/net/sock.h:2400 [inline]
sk_wake_async+0x108/0x290 include/net/sock.h:2396
unix_release_sock+0x79d/0xbc0 net/unix/af_unix.c:570
unix_release+0x84/0xe0 net/unix/af_unix.c:949
__sock_release+0xcd/0x280 net/socket.c:649
sock_close+0x18/0x20 net/socket.c:1314
__fput+0x286/0x9f0 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
get_signal+0x1b80/0x21d0 kernel/signal.c:2593
arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae

-> (&new->fa_lock){....}-{2:2} {
INITIAL USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_write_lock_irq include/linux/rwlock_api_smp.h:194 [inline]
_raw_write_lock_irq+0x32/0x50 kernel/locking/spinlock.c:316
fasync_remove_entry+0xb6/0x1f0 fs/fcntl.c:891
fasync_helper+0x9e/0xb0 fs/fcntl.c:994
sock_fasync+0x94/0x140 net/socket.c:1339
__fput+0x846/0x9f0 fs/file_table.c:277
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
INITIAL READ USE at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:1014 [inline]
kill_fasync fs/fcntl.c:1035 [inline]
kill_fasync+0x136/0x470 fs/fcntl.c:1028
sock_wake_async+0xd2/0x160 net/socket.c:1368
sk_wake_async include/net/sock.h:2400 [inline]
sk_wake_async+0x108/0x290 include/net/sock.h:2396
unix_release_sock+0x79d/0xbc0 net/unix/af_unix.c:570
unix_release+0x84/0xe0 net/unix/af_unix.c:949
__sock_release+0xcd/0x280 net/socket.c:649
sock_close+0x18/0x20 net/socket.c:1314
__fput+0x286/0x9f0 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
get_signal+0x1b80/0x21d0 kernel/signal.c:2593
arch_do_signal_or_restart+0x2a9/0x1c40 arch/x86/kernel/signal.c:868
handle_signal_work kernel/entry/common.c:148 [inline]
exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
exit_to_user_mode_prepare+0x17d/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
}
... key at: [<ffffffff90308bc0>] __key.0+0x0/0x40
... acquired at:
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:1014 [inline]
kill_fasync fs/fcntl.c:1035 [inline]
kill_fasync+0x136/0x470 fs/fcntl.c:1028
snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387
snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516
snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:697 [inline]
snd_timer_start sound/core/timer.c:690 [inline]
snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985
__snd_timer_user_ioctl.isra.0+0xda8/0x2490 sound/core/timer.c:2108
snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae

stack backtrace:
CPU: 1 PID: 27804 Comm: syz-executor.3 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_bad_irq_dependency kernel/locking/lockdep.c:2577 [inline]
check_irq_usage.cold+0x4c1/0x6b0 kernel/locking/lockdep.c:2816
check_prev_add kernel/locking/lockdep.c:3067 [inline]
check_prevs_add kernel/locking/lockdep.c:3186 [inline]
validate_chain kernel/locking/lockdep.c:3801 [inline]
__lock_acquire+0x2a1f/0x54a0 kernel/locking/lockdep.c:5027
lock_acquire kernel/locking/lockdep.c:5637 [inline]
lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5602
__raw_read_lock_irqsave include/linux/rwlock_api_smp.h:159 [inline]
_raw_read_lock_irqsave+0x70/0x90 kernel/locking/spinlock.c:236
kill_fasync_rcu fs/fcntl.c:1014 [inline]
kill_fasync fs/fcntl.c:1035 [inline]
kill_fasync+0x136/0x470 fs/fcntl.c:1028
snd_timer_user_ccallback+0x298/0x330 sound/core/timer.c:1387
snd_timer_notify1+0x11c/0x3b0 sound/core/timer.c:516
snd_timer_start1+0x4d4/0x800 sound/core/timer.c:578
snd_timer_start sound/core/timer.c:697 [inline]
snd_timer_start sound/core/timer.c:690 [inline]
snd_timer_user_start.isra.0+0x1e3/0x260 sound/core/timer.c:1985
__snd_timer_user_ioctl.isra.0+0xda8/0x2490 sound/core/timer.c:2108
snd_timer_user_ioctl+0x77/0xb0 sound/core/timer.c:2129
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:874 [inline]
__se_sys_ioctl fs/ioctl.c:860 [inline]
__x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f927e7d2ae9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f927bd48188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f927e8e5f60 RCX: 00007f927e7d2ae9
RDX: 0000000000000000 RSI: 00000000000054a0 RDI: 0000000000000003
RBP: 00007f927e82cf6d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffcc9c48d0f R14: 00007f927bd48300 R15: 0000000000022000
</TASK>

---
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