======================================================
WARNING: possible circular locking dependency detected
5.17.0-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor339/4068 is trying to acquire lock:
ffff8880774e3228 (&mm->mmap_lock#2){++++}-{3:3}, at: __might_fault+0x88/0x160 mm/memory.c:5317

but task is already holding lock:
ffff88801a542230 (&runtime->buffer_mutex){+.+.}-{3:3}, at: wait_for_avail sound/core/pcm_lib.c:1913 [inline]
ffff88801a542230 (&runtime->buffer_mutex){+.+.}-{3:3}, at: __snd_pcm_lib_xfer+0x9ca/0x1ab0 sound/core/pcm_lib.c:2263

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (&runtime->buffer_mutex){+.+.}-{3:3}:
       __mutex_lock_common kernel/locking/mutex.c:600 [inline]
       __mutex_lock+0x12f/0x12f0 kernel/locking/mutex.c:733
       snd_pcm_hw_params+0xbb/0x1740 sound/core/pcm_native.c:705
       snd_pcm_oss_change_params_locked+0x11a2/0x30a0 sound/core/oss/pcm_oss.c:976
       snd_pcm_oss_change_params sound/core/oss/pcm_oss.c:1116 [inline]
       snd_pcm_oss_mmap+0x391/0x4a0 sound/core/oss/pcm_oss.c:2929
       call_mmap include/linux/fs.h:2085 [inline]
       mmap_region+0x976/0x1200 mm/mmap.c:1791
       do_mmap+0x5c4/0xd70 mm/mmap.c:1582
       vm_mmap_pgoff+0x163/0x210 mm/util.c:519
       ksys_mmap_pgoff+0x2e8/0x490 mm/mmap.c:1628
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (&mm->mmap_lock#2){++++}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3065 [inline]
       check_prevs_add kernel/locking/lockdep.c:3188 [inline]
       validate_chain kernel/locking/lockdep.c:3803 [inline]
       __lock_acquire+0x2a44/0x5660 kernel/locking/lockdep.c:5029
       lock_acquire kernel/locking/lockdep.c:5641 [inline]
       lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606
       __might_fault mm/memory.c:5318 [inline]
       __might_fault+0xe6/0x160 mm/memory.c:5311
       _copy_to_user+0x20/0xc0 lib/usercopy.c:28
       copy_to_user include/linux/uaccess.h:160 [inline]
       default_read_copy+0xf1/0x160 sound/core/pcm_lib.c:2013
       __snd_pcm_lib_xfer+0x1148/0x1ab0 sound/core/pcm_lib.c:2282
       snd_pcm_oss_read3+0x16f/0x360 sound/core/oss/pcm_oss.c:1292
       snd_pcm_oss_read2+0x261/0x3b0 sound/core/oss/pcm_oss.c:1503
       snd_pcm_oss_read1 sound/core/oss/pcm_oss.c:1550 [inline]
       snd_pcm_oss_read+0x4a4/0x6a0 sound/core/oss/pcm_oss.c:2788
       vfs_read+0x15f/0x4b0 fs/read_write.c:480
       ksys_read+0xee/0x1c0 fs/read_write.c:620
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

other info that might help us debug this:

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&runtime->buffer_mutex);
                               lock(&mm->mmap_lock#2);
                               lock(&runtime->buffer_mutex);
  lock(&mm->mmap_lock#2);

 *** DEADLOCK ***

1 lock held by syz-executor339/4068:
 #0: ffff88801a542230 (&runtime->buffer_mutex){+.+.}-{3:3}, at: wait_for_avail sound/core/pcm_lib.c:1913 [inline]
 #0: ffff88801a542230 (&runtime->buffer_mutex){+.+.}-{3:3}, at: __snd_pcm_lib_xfer+0x9ca/0x1ab0 sound/core/pcm_lib.c:2263

stack backtrace:
CPU: 0 PID: 4068 Comm: syz-executor339 Not tainted 5.17.0-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+0x57/0x7d lib/dump_stack.c:106
 check_noncircular+0x25f/0x2e0 kernel/locking/lockdep.c:2145
 check_prev_add kernel/locking/lockdep.c:3065 [inline]
 check_prevs_add kernel/locking/lockdep.c:3188 [inline]
 validate_chain kernel/locking/lockdep.c:3803 [inline]
 __lock_acquire+0x2a44/0x5660 kernel/locking/lockdep.c:5029
 lock_acquire kernel/locking/lockdep.c:5641 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5606
 __might_fault mm/memory.c:5318 [inline]
 __might_fault+0xe6/0x160 mm/memory.c:5311
 _copy_to_user+0x20/0xc0 lib/usercopy.c:28
 copy_to_user include/linux/uaccess.h:160 [inline]
 default_read_copy+0xf1/0x160 sound/core/pcm_lib.c:2013
 __snd_pcm_lib_xfer+0x1148/0x1ab0 sound/core/pcm_lib.c:2282
 snd_pcm_oss_read3+0x16f/0x360 sound/core/oss/pcm_oss.c:1292
 snd_pcm_oss_read2+0x261/0x3b0 sound/core/oss/pcm_oss.c:1503
 snd_pcm_oss_read1 sound/core/oss/pcm_oss.c:1550 [inline]
 snd_pcm_oss_read+0x4a4/0x6a0 sound/core/oss/pcm_oss.c:2788
 vfs_read+0x15f/0x4b0 fs/read_write.c:480
 ksys_read+0xee/0x1c0 fs/read_write.c:620
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0x80 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f407434ec19
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fffea664128 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f407434ec19
RDX: 0000000000000ff2 RSI: 0000000020000780 RDI: 0000000000000004
RBP: 00007f4074312dc0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f4074312e50
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>