======================================================
WARNING: possible circular locking dependency detected
5.14.0-rc1-syzkaller #0 Not tainted
------------------------------------------------------
syz-executor190/8431 is trying to acquire lock:
ffff88801e3633e0 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x75a/0x1ba0 security/integrity/ima/ima_main.c:253

but task is already holding lock:
ffff8881488a8460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:375

which lock already depends on the new lock.


the existing dependency chain (in reverse order) is:

-> #1 (sb_writers#5){.+.+}-{0:0}:
       lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
       percpu_down_read include/linux/percpu-rwsem.h:51 [inline]
       __sb_start_write include/linux/fs.h:1763 [inline]
       sb_start_write+0x4f/0x1a0 include/linux/fs.h:1833
       mnt_want_write+0x3b/0x80 fs/namespace.c:375
       ovl_maybe_copy_up+0x117/0x180 fs/overlayfs/copy_up.c:996
       ovl_open+0xa2/0x200 fs/overlayfs/file.c:149
       do_dentry_open+0x7cb/0x1020 fs/open.c:826
       vfs_open fs/open.c:949 [inline]
       dentry_open+0xc6/0x120 fs/open.c:965
       ima_calc_file_hash+0x157/0x1b00 security/integrity/ima/ima_crypto.c:557
       ima_collect_measurement+0x283/0x520 security/integrity/ima/ima_api.c:252
       process_measurement+0xf79/0x1ba0 security/integrity/ima/ima_main.c:330
       ima_file_check+0xdb/0x130 security/integrity/ima/ima_main.c:499
       do_open fs/namei.c:3376 [inline]
       path_openat+0x284a/0x36b0 fs/namei.c:3507
       do_filp_open+0x253/0x4d0 fs/namei.c:3534
       do_sys_openat2+0x124/0x460 fs/open.c:1204
       do_sys_open fs/open.c:1220 [inline]
       __do_sys_open fs/open.c:1228 [inline]
       __se_sys_open fs/open.c:1224 [inline]
       __x64_sys_open+0x221/0x270 fs/open.c:1224
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
       entry_SYSCALL_64_after_hwframe+0x44/0xae

-> #0 (&iint->mutex){+.+.}-{3:3}:
       check_prev_add kernel/locking/lockdep.c:3051 [inline]
       check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174
       validate_chain kernel/locking/lockdep.c:3789 [inline]
       __lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015
       lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
       __mutex_lock_common+0x1ad/0x3770 kernel/locking/mutex.c:959
       __mutex_lock kernel/locking/mutex.c:1104 [inline]
       mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1119
       process_measurement+0x75a/0x1ba0 security/integrity/ima/ima_main.c:253
       ima_file_check+0xdb/0x130 security/integrity/ima/ima_main.c:499
       do_open fs/namei.c:3376 [inline]
       path_openat+0x284a/0x36b0 fs/namei.c:3507
       do_filp_open+0x253/0x4d0 fs/namei.c:3534
       do_sys_openat2+0x124/0x460 fs/open.c:1204
       do_sys_open fs/open.c:1220 [inline]
       __do_sys_openat fs/open.c:1236 [inline]
       __se_sys_openat fs/open.c:1231 [inline]
       __x64_sys_openat+0x243/0x290 fs/open.c:1231
       do_syscall_x64 arch/x86/entry/common.c:50 [inline]
       do_syscall_64+0x3d/0xb0 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(sb_writers#5);
                               lock(&iint->mutex);
                               lock(sb_writers#5);
  lock(&iint->mutex);

 *** DEADLOCK ***

1 lock held by syz-executor190/8431:
 #0: ffff8881488a8460 (sb_writers#5){.+.+}-{0:0}, at: mnt_want_write+0x3b/0x80 fs/namespace.c:375

stack backtrace:
CPU: 0 PID: 8431 Comm: syz-executor190 Not tainted 5.14.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1ae/0x29f lib/dump_stack.c:105
 print_circular_bug+0xb17/0xdc0 kernel/locking/lockdep.c:2009
 check_noncircular+0x2cc/0x390 kernel/locking/lockdep.c:2131
 check_prev_add kernel/locking/lockdep.c:3051 [inline]
 check_prevs_add+0x4f9/0x5b30 kernel/locking/lockdep.c:3174
 validate_chain kernel/locking/lockdep.c:3789 [inline]
 __lock_acquire+0x4476/0x6100 kernel/locking/lockdep.c:5015
 lock_acquire+0x182/0x4a0 kernel/locking/lockdep.c:5625
 __mutex_lock_common+0x1ad/0x3770 kernel/locking/mutex.c:959
 __mutex_lock kernel/locking/mutex.c:1104 [inline]
 mutex_lock_nested+0x1a/0x20 kernel/locking/mutex.c:1119
 process_measurement+0x75a/0x1ba0 security/integrity/ima/ima_main.c:253
 ima_file_check+0xdb/0x130 security/integrity/ima/ima_main.c:499
 do_open fs/namei.c:3376 [inline]
 path_openat+0x284a/0x36b0 fs/namei.c:3507
 do_filp_open+0x253/0x4d0 fs/namei.c:3534
 do_sys_openat2+0x124/0x460 fs/open.c:1204
 do_sys_open fs/open.c:1220 [inline]
 __do_sys_openat fs/open.c:1236 [inline]
 __se_sys_openat fs/open.c:1231 [inline]
 __x64_sys_openat+0x243/0x290 fs/open.c:1231
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x444d09
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 81 14 00 00 90 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 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2680c352f8 EFLAGS: 00000246 ORIG_RAX: 0000