======================================================
WARNING: possible circular locking dependency detected
syzkaller #0 Tainted: G             L     
------------------------------------------------------
udevd/5038 is trying to acquire lock:
ffff88810ab2f3f8 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xa4/0xca0

but task is already holding lock:
ffff888114b5e690 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #4 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}:
       __mutex_lock+0x19d/0x1550
       ima_file_truncate+0xb6/0x170
       security_file_truncate+0x118/0x240
       path_openat+0x1569/0x1d60
       do_file_open+0x23e/0x4a0
       do_sys_openat2+0x115/0x200
       __x64_sys_openat+0x138/0x170
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #3 (sb_writers#5){.+.+}-{0:0}:
       sb_start_write+0x4d/0x1d0
       mnt_want_write+0x41/0x90
       ovl_set_acl+0x36b/0x8a0
       vfs_set_acl+0x8a0/0xb50
       filename_setxattr+0x305/0x630
       path_setxattrat+0x408/0x450
       __x64_sys_setxattr+0xbc/0xe0
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #2 (&ovl_i_mutex_dir_key[depth]){++++}-{4:4}:
       down_read+0x4a/0x330
       lookup_slow+0x46/0x70
       path_lookupat+0x3f5/0x8c0
       filename_lookup+0x265/0x5d0
       kern_path+0x3d/0x150
       lookup_bdev+0xc8/0x2b0
       resume_store+0x16f/0x4f0
       kernfs_fop_write_iter+0x3a4/0x540
       vfs_write+0x612/0xba0
       ksys_write+0x150/0x270
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #1 (&of->mutex){+.+.}-{4:4}:
       __mutex_lock+0x19d/0x1550
       kernfs_seq_start+0x5d/0x420
       seq_read_iter+0x37e/0xca0
       copy_splice_read+0x5ff/0xaa0
       splice_direct_to_actor+0x48b/0xcb0
       do_splice_direct+0x195/0x290
       do_sendfile+0x52e/0x7c0
       __se_sys_sendfile64+0x144/0x1a0
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

-> #0 (&p->lock){+.+.}-{4:4}:
       __lock_acquire+0x1520/0x2cf0
       lock_acquire+0x106/0x350
       __mutex_lock+0x19d/0x1550
       seq_read_iter+0xa4/0xca0
       __kernel_read+0x4ca/0x960
       integrity_kernel_read+0x89/0xd0
       ima_calc_file_hash+0x451/0x890
       ima_collect_measurement+0x51b/0xa00
       process_measurement+0x1272/0x1c10
       ima_file_check+0xe1/0x130
       security_file_post_open+0xb3/0x260
       path_openat+0x1485/0x1d60
       do_file_open+0x23e/0x4a0
       do_sys_openat2+0x115/0x200
       __x64_sys_openat+0x138/0x170
       do_syscall_64+0x166/0x520
       entry_SYSCALL_64_after_hwframe+0x77/0x7f

other info that might help us debug this:

Chain exists of:
  &p->lock --> sb_writers#5 --> &ima_iint_mutex_key[depth]

 Possible unsafe locking scenario:

       CPU0                    CPU1
       ----                    ----
  lock(&ima_iint_mutex_key[depth]);
                               lock(sb_writers#5);
                               lock(&ima_iint_mutex_key[depth]);
  lock(&p->lock);

 *** DEADLOCK ***

locks held by udevd/5038: 1, last CPU#0:
 #0: ffff888114b5e690 (&ima_iint_mutex_key[depth]){+.+.}-{4:4}, at: process_measurement+0x7d0/0x1c10

stack backtrace:
CPU: 0 UID: 0 PID: 5038 Comm: udevd Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150
 print_circular_bug+0x2e1/0x300
 check_noncircular+0x12e/0x150
 __lock_acquire+0x1520/0x2cf0
 lock_acquire+0x106/0x350
 __mutex_lock+0x19d/0x1550
 seq_read_iter+0xa4/0xca0
 __kernel_read+0x4ca/0x960
 integrity_kernel_read+0x89/0xd0
 ima_calc_file_hash+0x451/0x890
 ima_collect_measurement+0x51b/0xa00
 process_measurement+0x1272/0x1c10
 ima_file_check+0xe1/0x130
 security_file_post_open+0xb3/0x260
 path_openat+0x1485/0x1d60
 do_file_open+0x23e/0x4a0
 do_sys_openat2+0x115/0x200
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0x166/0x520
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f0b9989a4
Code: 24 20 48 8d 44 24 30 48 89 44 24 28 64 8b 04 25 18 00 00 00 85 c0 75 2c 44 89 e2 48 89 ee bf 9c ff ff ff b8 01 01 00 00 0f 05 <48> 3d 00 f0 ff ff 76 60 48 8b 15 55 a4 0d 00 f7 d8 64 89 02 48 83
RSP: 002b:00007ffc8929dca0 EFLAGS: 00000246 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000008 RCX: 00007f5f0b9989a4
RDX: 0000000000080000 RSI: 00007ffc8929ddd8 RDI: 00000000ffffff9c
RBP: 00007ffc8929ddd8 R08: 0000000000000008 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000080000
R13: 000055bbfdd17b42 R14: 0000000000000001 R15: 0000000000000000
 </TASK>
