[info] Using makefile-style concurrent boot in runlevel 2. [ 27.748866] audit: type=1800 audit(1542469536.010:21): pid=5911 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="bootlogs" dev="sda1" ino=2419 res=0 [ 27.777892] audit: type=1800 audit(1542469536.020:22): pid=5911 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="motd" dev="sda1" ino=2447 res=0 [....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.88' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 54.393428] [ 54.395141] ====================================================== [ 54.401447] WARNING: possible circular locking dependency detected [ 54.407760] 4.20.0-rc2+ #117 Not tainted [ 54.411853] ------------------------------------------------------ [ 54.418166] syz-executor874/6070 is trying to acquire lock: [ 54.423847] 00000000403dc15a (&sb->s_type->i_mutex_key#11){+.+.}, at: shmem_fallocate+0x18b/0x12c0 [ 54.432930] [ 54.432930] but task is already holding lock: [ 54.439001] 0000000019817b16 (ashmem_mutex){+.+.}, at: ashmem_shrink_scan+0xb4/0x660 [ 54.447089] [ 54.447089] which lock already depends on the new lock. [ 54.447089] [ 54.455380] [ 54.455380] the existing dependency chain (in reverse order) is: [ 54.462981] [ 54.462981] -> #2 (ashmem_mutex){+.+.}: [ 54.468438] __mutex_lock+0x166/0x16f0 [ 54.472823] mutex_lock_nested+0x16/0x20 [ 54.477539] ashmem_mmap+0x55/0x520 [ 54.481913] mmap_region+0xe85/0x1cd0 [ 54.486216] do_mmap+0xa22/0x1230 [ 54.490169] vm_mmap_pgoff+0x213/0x2c0 [ 54.494555] ksys_mmap_pgoff+0x4da/0x660 [ 54.499114] __x64_sys_mmap+0xe9/0x1b0 [ 54.503608] do_syscall_64+0x1b9/0x820 [ 54.507996] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 54.513796] [ 54.513796] -> #1 (&mm->mmap_sem){++++}: [ 54.519417] down_read+0x8d/0x120 [ 54.523408] __do_page_fault+0xbc9/0xe60 [ 54.528069] do_page_fault+0xf2/0x7e0 [ 54.532369] page_fault+0x1e/0x30 [ 54.536328] iov_iter_fault_in_readable+0x363/0x450 [ 54.541849] generic_perform_write+0x216/0x6a0 [ 54.546927] __generic_file_write_iter+0x26e/0x630 [ 54.552360] generic_file_write_iter+0x34d/0x6b0 [ 54.557745] __vfs_write+0x6b8/0x9f0 [ 54.561973] vfs_write+0x1fc/0x560 [ 54.566030] ksys_write+0x101/0x260 [ 54.570169] __x64_sys_write+0x73/0xb0 [ 54.574592] do_syscall_64+0x1b9/0x820 [ 54.578983] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 54.584667] [ 54.584667] -> #0 (&sb->s_type->i_mutex_key#11){+.+.}: [ 54.591409] lock_acquire+0x1ed/0x520 [ 54.595708] down_write+0x8a/0x130 [ 54.599766] shmem_fallocate+0x18b/0x12c0 [ 54.604411] ashmem_shrink_scan+0x238/0x660 [ 54.609232] ashmem_ioctl+0x3ae/0x13a0 [ 54.613640] do_vfs_ioctl+0x1de/0x1790 [ 54.618035] ksys_ioctl+0xa9/0xd0 [ 54.621992] __x64_sys_ioctl+0x73/0xb0 [ 54.626378] do_syscall_64+0x1b9/0x820 [ 54.630763] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 54.636559] [ 54.636559] other info that might help us debug this: [ 54.636559] [ 54.644687] Chain exists of: [ 54.644687] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 54.644687] [ 54.656218] Possible unsafe locking scenario: [ 54.656218] [ 54.662252] CPU0 CPU1 [ 54.666909] ---- ---- [ 54.671582] lock(ashmem_mutex); [ 54.675012] lock(&mm->mmap_sem); [ 54.681070] lock(ashmem_mutex); [ 54.687072] lock(&sb->s_type->i_mutex_key#11); [ 54.691806] [ 54.691806] *** DEADLOCK *** [ 54.691806] [ 54.697840] 1 lock held by syz-executor874/6070: [ 54.702583] #0: 0000000019817b16 (ashmem_mutex){+.+.}, at: ashmem_shrink_scan+0xb4/0x660 [ 54.710879] [ 54.710879] stack backtrace: [ 54.715484] CPU: 1 PID: 6070 Comm: syz-executor874 Not tainted 4.20.0-rc2+ #117 [ 54.722902] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.732231] Call Trace: [ 54.734799] dump_stack+0x244/0x39d [ 54.738526] ? dump_stack_print_info.cold.1+0x20/0x20 [ 54.743844] ? vprintk_func+0x85/0x181 [ 54.747712] print_circular_bug.isra.35.cold.54+0x1bd/0x27d [ 54.753404] ? save_trace+0xe0/0x290 [ 54.757107] __lock_acquire+0x3399/0x4c20 [ 54.761238] ? mark_held_locks+0x130/0x130 [ 54.765453] ? __switch_to_asm+0x40/0x70 [ 54.769488] ? __switch_to_asm+0x40/0x70 [ 54.773522] ? __switch_to_asm+0x34/0x70 [ 54.777574] ? __switch_to_asm+0x34/0x70 [ 54.781625] ? __switch_to_asm+0x40/0x70 [ 54.785661] ? __switch_to_asm+0x34/0x70 [ 54.789700] ? __switch_to_asm+0x40/0x70 [ 54.793756] ? __schedule+0x8d7/0x21d0 [ 54.797623] ? __sched_text_start+0x8/0x8 [ 54.801797] ? check_preemption_disabled+0x48/0x280 [ 54.806799] ? find_held_lock+0x36/0x1c0 [ 54.810951] ? print_usage_bug+0xc0/0xc0 [ 54.815113] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 54.820199] ? _raw_spin_unlock_irqrestore+0x82/0xd0 [ 54.825286] ? lockdep_hardirqs_on+0x3bb/0x5b0 [ 54.829847] ? preempt_schedule+0x4d/0x60 [ 54.833975] ? __lock_is_held+0xb5/0x140 [ 54.838030] lock_acquire+0x1ed/0x520 [ 54.841812] ? shmem_fallocate+0x18b/0x12c0 [ 54.846111] ? lock_release+0xa00/0xa00 [ 54.850102] ? perf_trace_sched_process_exec+0x860/0x860 [ 54.855561] ? mark_held_locks+0x130/0x130 [ 54.859803] down_write+0x8a/0x130 [ 54.863317] ? shmem_fallocate+0x18b/0x12c0 [ 54.867612] ? down_read+0x120/0x120 [ 54.871480] ? __lock_acquire+0x62f/0x4c20 [ 54.875725] shmem_fallocate+0x18b/0x12c0 [ 54.879850] ? mark_held_locks+0x130/0x130 [ 54.884058] ? shmem_setattr+0xda0/0xda0 [ 54.888116] ? drop_futex_key_refs.isra.14+0x6d/0xe0 [ 54.893337] ? futex_wake+0x304/0x760 [ 54.897125] ? get_futex_key+0x21b0/0x21b0 [ 54.901344] ? lock_acquire+0x1ed/0x520 [ 54.905431] ? ashmem_shrink_scan+0xb4/0x660 [ 54.909834] ? lock_downgrade+0x900/0x900 [ 54.913977] ? check_preemption_disabled+0x48/0x280 [ 54.919076] ? lock_release+0xa00/0xa00 [ 54.923048] ? zap_class+0x640/0x640 [ 54.926742] ? do_futex+0x249/0x26d0 [ 54.930453] ? mutex_trylock+0x24c/0x2b0 [ 54.934657] ? ashmem_shrink_scan+0xb4/0x660 [ 54.939044] ? __ww_mutex_check_waiters+0x160/0x160 [ 54.944061] ashmem_shrink_scan+0x238/0x660 [ 54.948371] ? cap_capable+0x1f9/0x260 [ 54.952425] ? ashmem_release+0x190/0x190 [ 54.956658] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 54.962174] ? ns_capable_common+0x13f/0x170 [ 54.966557] ashmem_ioctl+0x3ae/0x13a0 [ 54.970566] ? __fget+0x4d1/0x740 [ 54.974104] ? ashmem_shrink_scan+0x660/0x660 [ 54.978577] ? ksys_dup3+0x680/0x680 [ 54.982268] ? up_write+0x150/0x220 [ 54.985872] ? smack_privileged+0xd0/0xd0 [ 54.990002] ? ashmem_shrink_scan+0x660/0x660 [ 54.994499] do_vfs_ioctl+0x1de/0x1790 [ 54.998364] ? ioctl_preallocate+0x300/0x300 [ 55.002760] ? memset+0x31/0x40 [ 55.006034] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.011547] ? smack_file_ioctl+0x210/0x3c0 [ 55.015850] ? fget_raw+0x20/0x20 [ 55.019296] ? smack_file_lock+0x2e0/0x2e0 [ 55.023513] ? __x64_sys_futex+0x47f/0x6a0 [ 55.027727] ? do_syscall_64+0x9a/0x820 [ 55.031778] ? do_syscall_64+0x9a/0x820 [ 55.035734] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 55.041252] ? security_file_ioctl+0x94/0xc0 [ 55.045780] ksys_ioctl+0xa9/0xd0 [ 55.049372] __x64_sys_ioctl+0x73/0xb0 [ 55.053240] do_syscall_64+0x1b9/0x820 [ 55.057103] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 55.062445] ? syscall_return_slowpath+0x5e0/0x5e0 [ 55.067361] ? trace_hardirqs_on_caller+0x310/0x310 [ 55.072363] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 55.077365] ? post_copy_siginfo_from_user.isra.25.part.26+0x250/0x250 [ 55.084071] ? __switch_to_asm+0x40/0x70 [ 55.088113] ? __switch_to_asm+0x34/0x70 [ 55.092253] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 55.097074] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 55.102235] RIP: 0033:0x446329 [ 55.105407] Code: e8 2c b3 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 2b 09 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 55.124286] RSP: 002b:00007ff3c438ada8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 [ 55.131975] RAX: ffffffffffffffda RBX: 00000000006dac38 RCX: 0000000000446329 [ 55.139239] RDX: 0000000000000000 RSI: 000000000000770a RDI: 0000000000000004 executing program [ 55.146489] RBP: 00000000006dac30 R08: 0000000000000000 R09: 0000000000000000 [ 55.153738] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006dac3c [ 55.160988] R13: dfdd4f11168a8b2b R14: 6873612f7665642f R15: 00000000006dad2c executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program