[ 34.443274] audit: type=1800 audit(1549974968.854:27): pid=7412 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 res=0 [ 34.473190] audit: type=1800 audit(1549974968.864:28): pid=7412 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="ssh" dev="sda1" ino=2417 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.506736] audit: type=1800 audit(1549974969.974:29): pid=7412 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 35.526439] audit: type=1800 audit(1549974969.974:30): pid=7412 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.121' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program syzkaller login: [ 783.957244] hrtimer: interrupt took 25358 ns 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 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 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 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 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 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 858.347719] [ 858.349401] ====================================================== [ 858.355706] WARNING: possible circular locking dependency detected [ 858.362027] 5.0.0-rc6+ #69 Not tainted [ 858.365905] ------------------------------------------------------ [ 858.372209] syz-executor856/12159 is trying to acquire lock: [ 858.377989] 0000000095714537 (&mm->mmap_sem){++++}, at: __do_page_fault+0x9c2/0xd60 [ 858.385795] [ 858.385795] but task is already holding lock: [ 858.391749] 000000003fdbddc5 (&sb->s_type->i_mutex_key#12){+.+.}, at: generic_file_write_iter+0xdf/0x610 [ 858.401374] [ 858.401374] which lock already depends on the new lock. [ 858.401374] [ 858.409678] [ 858.409678] the existing dependency chain (in reverse order) is: [ 858.417272] [ 858.417272] -> #2 (&sb->s_type->i_mutex_key#12){+.+.}: [ 858.424018] down_write+0x38/0x90 [ 858.427975] shmem_fallocate+0x15a/0xc60 [ 858.432538] ashmem_shrink_scan+0x1d7/0x4f0 [ 858.437359] ashmem_ioctl+0x2f0/0x11a0 [ 858.441765] do_vfs_ioctl+0xd6e/0x1390 [ 858.446151] ksys_ioctl+0xab/0xd0 [ 858.450116] __x64_sys_ioctl+0x73/0xb0 [ 858.454507] do_syscall_64+0x103/0x610 [ 858.458897] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 858.464599] [ 858.464599] -> #1 (ashmem_mutex){+.+.}: [ 858.470033] __mutex_lock+0xf7/0x1310 [ 858.474331] mutex_lock_nested+0x16/0x20 [ 858.478889] ashmem_mmap+0x55/0x520 [ 858.483013] mmap_region+0xc37/0x1760 [ 858.487311] do_mmap+0x8e2/0x1080 [ 858.491261] vm_mmap_pgoff+0x1c5/0x230 [ 858.495653] ksys_mmap_pgoff+0x4aa/0x630 [ 858.500209] __x64_sys_mmap+0xe9/0x1b0 [ 858.504611] do_syscall_64+0x103/0x610 [ 858.508996] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 858.514677] [ 858.514677] -> #0 (&mm->mmap_sem){++++}: [ 858.520197] lock_acquire+0x16f/0x3f0 [ 858.524513] down_read+0x3b/0x90 [ 858.528391] __do_page_fault+0x9c2/0xd60 [ 858.532966] do_page_fault+0x71/0x581 [ 858.537264] page_fault+0x1e/0x30 [ 858.541219] iov_iter_fault_in_readable+0x377/0x450 [ 858.546734] generic_perform_write+0x195/0x530 [ 858.551812] __generic_file_write_iter+0x25e/0x630 [ 858.557240] generic_file_write_iter+0x360/0x610 [ 858.562495] __vfs_write+0x613/0x8e0 [ 858.566705] vfs_write+0x20c/0x580 [ 858.570739] ksys_write+0xea/0x1f0 [ 858.574896] __x64_sys_write+0x73/0xb0 [ 858.579356] do_syscall_64+0x103/0x610 [ 858.583750] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 858.589431] [ 858.589431] other info that might help us debug this: [ 858.589431] [ 858.597544] Chain exists of: [ 858.597544] &mm->mmap_sem --> ashmem_mutex --> &sb->s_type->i_mutex_key#12 [ 858.597544] [ 858.609053] Possible unsafe locking scenario: [ 858.609053] [ 858.615112] CPU0 CPU1 [ 858.619782] ---- ---- [ 858.624423] lock(&sb->s_type->i_mutex_key#12); [ 858.629154] lock(ashmem_mutex); [ 858.635098] lock(&sb->s_type->i_mutex_key#12); [ 858.642344] lock(&mm->mmap_sem); [ 858.645861] [ 858.645861] *** DEADLOCK *** [ 858.645861] [ 858.651896] 2 locks held by syz-executor856/12159: [ 858.656798] #0: 00000000551238bf (sb_writers#5){.+.+}, at: vfs_write+0x429/0x580 [ 858.664405] #1: 000000003fdbddc5 (&sb->s_type->i_mutex_key#12){+.+.}, at: generic_file_write_iter+0xdf/0x610 [ 858.674442] [ 858.674442] stack backtrace: [ 858.678912] CPU: 0 PID: 12159 Comm: syz-executor856 Not tainted 5.0.0-rc6+ #69 [ 858.686248] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 858.695576] Call Trace: [ 858.698148] dump_stack+0x172/0x1f0 [ 858.701758] print_circular_bug.isra.0.cold+0x1cc/0x28f [ 858.707110] __lock_acquire+0x2f00/0x4700 [ 858.711239] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 858.715972] ? lockdep_hardirqs_on+0x415/0x5d0 [ 858.720547] ? retint_kernel+0x2d/0x2d [ 858.724941] ? mark_held_locks+0x100/0x100 [ 858.729152] ? mark_held_locks+0xb1/0x100 [ 858.733277] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 858.738010] ? lockdep_hardirqs_on+0x415/0x5d0 [ 858.742572] ? retint_kernel+0x2d/0x2d [ 858.746439] ? __lock_is_held+0xb6/0x140 [ 858.750482] lock_acquire+0x16f/0x3f0 [ 858.754264] ? __do_page_fault+0x9c2/0xd60 [ 858.758491] down_read+0x3b/0x90 [ 858.761847] ? __do_page_fault+0x9c2/0xd60 [ 858.766061] __do_page_fault+0x9c2/0xd60 [ 858.770106] do_page_fault+0x71/0x581 [ 858.773889] page_fault+0x1e/0x30 [ 858.777327] RIP: 0010:iov_iter_fault_in_readable+0x377/0x450 [ 858.783108] Code: 89 f6 41 88 57 e0 e8 f8 1e 47 fe 45 85 f6 74 c1 e9 70 fe ff ff e8 69 1d 47 fe 0f 1f 00 0f ae e8 44 89 f0 48 8b 8d 68 ff ff ff <8a> 11 89 c3 0f 1f 00 41 88 57 d0 31 ff 89 de e8 c5 1e 47 fe 85 db [ 858.801988] RSP: 0018:ffff88808bc1f9b8 EFLAGS: 00010293 [ 858.807327] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000002020053f [ 858.814579] RDX: 0000000000000000 RSI: ffffffff8328c3b7 RDI: 0000000000000007 [ 858.821861] RBP: ffff88808bc1fa58 R08: ffff88809fc22080 R09: fffff94000410a6f [ 858.829110] R10: fffff94000410a6e R11: ffffea0002085377 R12: 0000000000001000 [ 858.836368] R13: 0000000000001000 R14: 0000000000000000 R15: ffff88808bc1fa30 [ 858.843638] ? iov_iter_fault_in_readable+0x367/0x450 [ 858.848829] ? iov_iter_fault_in_readable+0x367/0x450 [ 858.853999] ? copy_page_from_iter+0x750/0x750 [ 858.858564] generic_perform_write+0x195/0x530 [ 858.863124] ? page_endio+0x780/0x780 [ 858.866913] ? current_time+0x140/0x140 [ 858.870866] ? lock_acquire+0x16f/0x3f0 [ 858.874820] __generic_file_write_iter+0x25e/0x630 [ 858.880088] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 858.885085] generic_file_write_iter+0x360/0x610 [ 858.889820] ? __generic_file_write_iter+0x630/0x630 [ 858.894928] ? trace_hardirqs_on_caller+0x6a/0x220 [ 858.899849] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 858.905366] ? iov_iter_init+0xea/0x220 [ 858.909320] __vfs_write+0x613/0x8e0 [ 858.913014] ? kernel_read+0x120/0x120 [ 858.916883] ? rcu_read_lock_sched_held+0x110/0x130 [ 858.921873] ? rcu_sync_lockdep_assert+0x73/0xb0 [ 858.926607] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 858.932121] ? __sb_start_write+0x1ac/0x360 [ 858.936421] vfs_write+0x20c/0x580 [ 858.939945] ksys_write+0xea/0x1f0 [ 858.943472] ? __ia32_sys_read+0xb0/0xb0 [ 858.947518] __x64_sys_write+0x73/0xb0 [ 858.951416] ? do_syscall_64+0x5b/0x610 [ 858.955376] do_syscall_64+0x103/0x610 [ 858.959249] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 858.964422] RIP: 0033:0x4476f9 [ 858.967600] Code: e8 dc e6 ff ff 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 4b 07 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 858.986481] RSP: 002b:00007fd81d346ce8 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 858.994183] RAX: ffffffffffffffda RBX: 00000000006ddc28 RCX: 00000000004476f9 [ 859.001442] RDX: 00000000fffffda2 RSI: 0000000020000540 RDI: 0000000000000005 [ 859.008686] RBP: 00000000006ddc20 R08: 0000000000000000 R09: 0000000000000000 [ 859.015932] R10: 0000000000000000 R11: 0000000000000246 R12: 00000000006ddc2c [ 859.023197] R13: 00007ffec697a92f R14: 00007fd81d3479c0 R15: 20c49ba5e353f7cf 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