Warning: Permanently added '10.128.0.208' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 71.477925][ T8510] [ 71.479082][ T8511] overlayfs: upperdir is in-use as upperdir/workdir of another mount, mount with '-o index=off' to override exclusive upperdir protection. [ 71.480292][ T8510] ====================================================== [ 71.501423][ T8510] WARNING: possible circular locking dependency detected [ 71.508445][ T8510] 5.10.0-rc5-next-20201127-syzkaller #0 Not tainted [ 71.515019][ T8510] ------------------------------------------------------ [ 71.522028][ T8510] syz-executor634/8510 is trying to acquire lock: [ 71.528425][ T8510] ffff8880151a1500 (&iint->mutex){+.+.}-{3:3}, at: process_measurement+0x363/0x1760 [ 71.537823][ T8510] [ 71.537823][ T8510] but task is already holding lock: [ 71.545185][ T8510] ffff888021f6a460 (sb_writers#4){.+.+}-{0:0}, at: path_openat+0x1a3d/0x2730 [ 71.553964][ T8510] [ 71.553964][ T8510] which lock already depends on the new lock. [ 71.553964][ T8510] [ 71.564353][ T8510] [ 71.564353][ T8510] the existing dependency chain (in reverse order) is: [ 71.573365][ T8510] [ 71.573365][ T8510] -> #1 (sb_writers#4){.+.+}-{0:0}: [ 71.580757][ T8510] mnt_want_write+0x69/0x3d0 [ 71.585860][ T8510] ovl_maybe_copy_up+0x11f/0x190 [ 71.591306][ T8510] ovl_open+0xba/0x270 [ 71.595886][ T8510] do_dentry_open+0x4b9/0x11b0 [ 71.601179][ T8510] dentry_open+0x132/0x1d0 [ 71.606110][ T8510] ima_calc_file_hash+0x32b/0x5a0 [ 71.611643][ T8510] ima_collect_measurement+0x4ca/0x570 [ 71.617613][ T8510] process_measurement+0xca6/0x1760 [ 71.623843][ T8510] ima_file_check+0xb9/0x100 [ 71.628942][ T8510] path_openat+0x154d/0x2730 [ 71.634055][ T8510] do_filp_open+0x17e/0x3c0 [ 71.639074][ T8510] do_sys_openat2+0x16d/0x420 [ 71.644318][ T8510] __x64_sys_open+0x119/0x1c0 [ 71.649518][ T8510] do_syscall_64+0x2d/0x70 [ 71.654464][ T8510] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 71.660862][ T8510] [ 71.660862][ T8510] -> #0 (&iint->mutex){+.+.}-{3:3}: [ 71.668245][ T8510] __lock_acquire+0x2ade/0x5500 [ 71.673606][ T8510] lock_acquire+0x29d/0x740 [ 71.678620][ T8510] __mutex_lock+0x134/0x1110 [ 71.683721][ T8510] process_measurement+0x363/0x1760 [ 71.689457][ T8510] ima_file_check+0xb9/0x100 [ 71.694560][ T8510] path_openat+0x154d/0x2730 [ 71.700615][ T8510] do_filp_open+0x17e/0x3c0 [ 71.705635][ T8510] do_sys_openat2+0x16d/0x420 [ 71.710822][ T8510] __x64_sys_openat+0x13f/0x1f0 [ 71.716182][ T8510] do_syscall_64+0x2d/0x70 [ 71.721111][ T8510] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 71.727511][ T8510] [ 71.727511][ T8510] other info that might help us debug this: [ 71.727511][ T8510] [ 71.737723][ T8510] Possible unsafe locking scenario: [ 71.737723][ T8510] [ 71.745164][ T8510] CPU0 CPU1 [ 71.750517][ T8510] ---- ---- [ 71.755866][ T8510] lock(sb_writers#4); [ 71.760020][ T8510] lock(&iint->mutex); [ 71.766682][ T8510] lock(sb_writers#4); [ 71.773351][ T8510] lock(&iint->mutex); [ 71.777497][ T8510] [ 71.777497][ T8510] *** DEADLOCK *** [ 71.777497][ T8510] [ 71.785633][ T8510] 1 lock held by syz-executor634/8510: [ 71.791081][ T8510] #0: ffff888021f6a460 (sb_writers#4){.+.+}-{0:0}, at: path_openat+0x1a3d/0x2730 [ 71.800316][ T8510] [ 71.800316][ T8510] stack backtrace: [ 71.806203][ T8510] CPU: 1 PID: 8510 Comm: syz-executor634 Not tainted 5.10.0-rc5-next-20201127-syzkaller #0 [ 71.816161][ T8510] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 71.826205][ T8510] Call Trace: [ 71.829497][ T8510] dump_stack+0x107/0x163 [ 71.833819][ T8510] check_noncircular+0x25f/0x2e0 [ 71.838748][ T8510] ? print_circular_bug+0x480/0x480 [ 71.843948][ T8510] ? __bfs+0x27a/0x690 [ 71.848015][ T8510] ? lockdep_lock+0xc6/0x200 [ 71.852597][ T8510] ? call_rcu_zapped+0xb0/0xb0 [ 71.857350][ T8510] __lock_acquire+0x2ade/0x5500 [ 71.862194][ T8510] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 71.868168][ T8510] ? call_rcu_zapped+0xb0/0xb0 [ 71.873108][ T8510] lock_acquire+0x29d/0x740 [ 71.877603][ T8510] ? process_measurement+0x363/0x1760 [ 71.882965][ T8510] ? lock_release+0x710/0x710 [ 71.887637][ T8510] __mutex_lock+0x134/0x1110 [ 71.892215][ T8510] ? process_measurement+0x363/0x1760 [ 71.897574][ T8510] ? process_measurement+0x7a5/0x1760 [ 71.902940][ T8510] ? lock_downgrade+0x6d0/0x6d0 [ 71.907779][ T8510] ? process_measurement+0x363/0x1760 [ 71.913162][ T8510] ? mutex_lock_io_nested+0xf60/0xf60 [ 71.918526][ T8510] ? up_write+0x191/0x560 [ 71.922889][ T8510] ? downgrade_write+0x3a0/0x3a0 [ 71.927816][ T8510] ? do_raw_read_unlock+0x3b/0x70 [ 71.932835][ T8510] ? _raw_read_unlock+0x24/0x40 [ 71.937676][ T8510] ? integrity_iint_find+0x123/0x150 [ 71.942956][ T8510] process_measurement+0x363/0x1760 [ 71.948149][ T8510] ? mmap_violation_check+0x1e0/0x1e0 [ 71.953538][ T8510] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 71.959512][ T8510] ? dquot_initialize_needed+0x290/0x290 [ 71.965161][ T8510] ? find_held_lock+0x2d/0x110 [ 71.969918][ T8510] ? aa_get_task_label+0x25d/0x540 [ 71.975018][ T8510] ? lock_downgrade+0x6d0/0x6d0 [ 71.979860][ T8510] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 71.986107][ T8510] ? aa_get_task_label+0x27f/0x540 [ 71.991209][ T8510] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 71.997440][ T8510] ? apparmor_task_getsecid+0xc2/0x110 [ 72.002889][ T8510] ima_file_check+0xb9/0x100 [ 72.007470][ T8510] ? process_measurement+0x1760/0x1760 [ 72.012926][ T8510] ? __sanitizer_cov_trace_const_cmp4+0x1c/0x70 [ 72.019154][ T8510] path_openat+0x154d/0x2730 [ 72.023735][ T8510] ? path_lookupat+0x830/0x830 [ 72.028505][ T8510] ? lockdep_hardirqs_on_prepare+0x400/0x400 [ 72.034483][ T8510] do_filp_open+0x17e/0x3c0 [ 72.038975][ T8510] ? may_open_dev+0xf0/0xf0 [ 72.043471][ T8510] ? do_raw_spin_lock+0x120/0x2b0 [ 72.048505][ T8510] ? rwlock_bug.part.0+0x90/0x90 [ 72.053434][ T8510] ? __sanitizer_cov_trace_const_cmp8+0x1d/0x70 [ 72.060550][ T8510] ? _raw_spin_unlock+0x24/0x40 [ 72.065482][ T8510] ? alloc_fd+0x2bc/0x640 [ 72.069806][ T8510] do_sys_openat2+0x16d/0x420 [ 72.074474][ T8510] ? build_open_flags+0x650/0x650 [ 72.079510][ T8510] __x64_sys_openat+0x13f/0x1f0 [ 72.084374][ T8510] ? __ia32_sys_open+0x1c0/0x1c0 [ 72.089308][ T8510] ? syscall_enter_from_user_mode+0x1d/0x50 [ 72.095892][ T8510] do_syscall_64+0x2d/0x70 [ 72.100316][ T8510] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 72.106206][ T8510] RIP: 0033:0x445aa9 [ 72.110125][ T8510] Code: e8 bc b7 02 00 48 83 c4 18 c3 0f 1f 80 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 0f 83 ab 11 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 72.12