[....] Starting enhanced syslogd: rsyslogd[ 15.171742] audit: type=1400 audit(1520278526.761:5): avc: denied { syslog } for pid=3881 comm="rsyslogd" capability=34 scontext=system_u:system_r:kernel_t:s0 tcontext=system_u:system_r:kernel_t:s0 tclass=capability2 permissive=1 [?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. Starting mcstransd: [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 18.890197] audit: type=1400 audit(1520278530.480:6): avc: denied { map } for pid=4022 comm="bash" path="/bin/bash" dev="sda1" ino=1457 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:file_t:s0 tclass=file permissive=1 Warning: Permanently added '10.128.0.45' (ECDSA) to the list of known hosts. [ 25.200113] audit: type=1400 audit(1520278536.789:7): avc: denied { map } for pid=4036 comm="syz-execprog" path="/root/syz-execprog" dev="sda1" ino=16479 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 2018/03/05 19:35:37 parsed 1 programs 2018/03/05 19:35:37 executed programs: 0 [ 25.442194] audit: type=1400 audit(1520278537.031:8): avc: denied { map } for pid=4036 comm="syz-execprog" path="/root/syzkaller-shm353921545" dev="sda1" ino=16482 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:file_t:s0 tclass=file permissive=1 [ 25.456104] IPVS: ftp: loaded support on port[0] = 21 [ 25.498891] audit: type=1400 audit(1520278537.088:9): avc: denied { map } for pid=4044 comm="syz-executor0" path="/dev/ashmem" dev="devtmpfs" ino=1133 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 25.499274] [ 25.525079] ====================================================== [ 25.531364] WARNING: possible circular locking dependency detected [ 25.537657] 4.16.0-rc4+ #251 Not tainted [ 25.541697] ------------------------------------------------------ [ 25.547983] syz-executor0/4044 is trying to acquire lock: [ 25.553486] (&sb->s_type->i_mutex_key#11){++++}, at: [<000000009995e3ea>] shmem_file_llseek+0xef/0x240 [ 25.563001] [ 25.563001] but task is already holding lock: [ 25.568949] (ashmem_mutex){+.+.}, at: [<0000000025863841>] ashmem_llseek+0x56/0x1f0 [ 25.576813] [ 25.576813] which lock already depends on the new lock. [ 25.576813] [ 25.585115] [ 25.585115] the existing dependency chain (in reverse order) is: [ 25.592702] [ 25.592702] -> #2 (ashmem_mutex){+.+.}: [ 25.598143] __mutex_lock+0x16f/0x1a80 [ 25.602521] mutex_lock_nested+0x16/0x20 [ 25.607075] ashmem_mmap+0x53/0x410 [ 25.611193] mmap_region+0xa99/0x15a0 [ 25.615484] do_mmap+0x6c0/0xe00 [ 25.619345] vm_mmap_pgoff+0x1de/0x280 [ 25.623730] SyS_mmap_pgoff+0x462/0x5f0 [ 25.628196] do_fast_syscall_32+0x3ec/0xf9f [ 25.633010] entry_SYSENTER_compat+0x70/0x7f [ 25.637913] [ 25.637913] -> #1 (&mm->mmap_sem){++++}: [ 25.643431] __might_fault+0x13a/0x1d0 [ 25.647813] _copy_to_user+0x2c/0xc0 [ 25.652018] filldir+0x1a7/0x320 [ 25.655878] dcache_readdir+0x12d/0x5e0 [ 25.660347] iterate_dir+0x1ca/0x530 [ 25.664554] SyS_getdents+0x225/0x450 [ 25.668848] do_syscall_64+0x281/0x940 [ 25.673236] entry_SYSCALL_64_after_hwframe+0x42/0xb7 [ 25.678913] [ 25.678913] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.685644] lock_acquire+0x1d5/0x580 [ 25.689942] down_write+0x87/0x120 [ 25.693973] shmem_file_llseek+0xef/0x240 [ 25.698611] vfs_llseek+0xa2/0xd0 [ 25.702556] ashmem_llseek+0xe7/0x1f0 [ 25.706846] compat_SyS_lseek+0xeb/0x170 [ 25.711399] do_fast_syscall_32+0x3ec/0xf9f [ 25.716223] entry_SYSENTER_compat+0x70/0x7f [ 25.721118] [ 25.721118] other info that might help us debug this: [ 25.721118] [ 25.729230] Chain exists of: [ 25.729230] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.729230] [ 25.740733] Possible unsafe locking scenario: [ 25.740733] [ 25.746763] CPU0 CPU1 [ 25.751404] ---- ---- [ 25.756041] lock(ashmem_mutex); [ 25.759466] lock(&mm->mmap_sem); [ 25.765509] lock(ashmem_mutex); [ 25.771456] lock(&sb->s_type->i_mutex_key#11); [ 25.776182] [ 25.776182] *** DEADLOCK *** [ 25.776182] [ 25.782211] 1 lock held by syz-executor0/4044: [ 25.786759] #0: (ashmem_mutex){+.+.}, at: [<0000000025863841>] ashmem_llseek+0x56/0x1f0 [ 25.795055] [ 25.795055] stack backtrace: [ 25.799525] CPU: 1 PID: 4044 Comm: syz-executor0 Not tainted 4.16.0-rc4+ #251 [ 25.806854] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.816177] Call Trace: [ 25.818739] dump_stack+0x194/0x24d [ 25.822338] ? arch_local_irq_restore+0x53/0x53 [ 25.826981] print_circular_bug.isra.38+0x2cd/0x2dc [ 25.831967] ? save_trace+0xe0/0x2b0 [ 25.835651] __lock_acquire+0x30a8/0x3e00 [ 25.839772] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.844939] ? ashmem_llseek+0x56/0x1f0 [ 25.848887] ? lock_release+0xa40/0xa40 [ 25.852832] ? check_same_owner+0x320/0x320 [ 25.857121] ? do_futex+0x86f/0x22a0 [ 25.860808] ? rcu_note_context_switch+0x710/0x710 [ 25.865707] ? vma_set_page_prot+0x16b/0x230 [ 25.870088] ? __might_sleep+0x95/0x190 [ 25.874034] ? ashmem_llseek+0x56/0x1f0 [ 25.877980] ? __mutex_lock+0x16f/0x1a80 [ 25.882018] ? ashmem_llseek+0x56/0x1f0 [ 25.885965] ? mmap_region+0x52e/0x15a0 [ 25.889911] ? ashmem_llseek+0x56/0x1f0 [ 25.893860] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.898671] ? find_held_lock+0x35/0x1d0 [ 25.902703] ? lock_downgrade+0x980/0x980 [ 25.906828] lock_acquire+0x1d5/0x580 [ 25.910600] ? lock_acquire+0x1d5/0x580 [ 25.914544] ? shmem_file_llseek+0xef/0x240 [ 25.918841] ? lock_release+0xa40/0xa40 [ 25.922787] ? check_same_owner+0x320/0x320 [ 25.927095] ? security_mmap_file+0x143/0x180 [ 25.931568] ? rcu_note_context_switch+0x710/0x710 [ 25.936468] ? __fget_light+0x2b2/0x3c0 [ 25.940425] ? __might_sleep+0x95/0x190 [ 25.944373] down_write+0x87/0x120 [ 25.947890] ? shmem_file_llseek+0xef/0x240 [ 25.952181] ? down_read+0x150/0x150 [ 25.955865] ? perf_trace_sched_switch+0x753/0xf60 [ 25.960768] shmem_file_llseek+0xef/0x240 [ 25.964896] ? shmem_free_swap+0x80/0x80 [ 25.968929] vfs_llseek+0xa2/0xd0 [ 25.972352] ashmem_llseek+0xe7/0x1f0 [ 25.976129] ? ashmem_read_iter+0x230/0x230 [ 25.980422] compat_SyS_lseek+0xeb/0x170 [ 25.984454] ? SyS_lseek+0x170/0x170 [ 25.988138] do_fast_syscall_32+0x3ec/0xf9f [ 25.992439] ? do_int80_syscall_32+0x9c0/0x9c0 [ 25.996993] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.001724] ? syscall_return_slowpath+0x2ac/0x550 [ 26.006625] ? prepare_exit_to_usermode+0x350/0x350 [ 26.011613] ? sysret32_from_system_call+0x5/0x3c [ 26.016427] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 26.021240] entry_SYSENTER_compat+0x70/0x7f [ 26.025619] RIP: 0023:0xf7ffcc99 [ 26.028952] RSP: 002b:00000000ff8bf66c EFLAGS: 00000282 ORIG_RAX: 0000000000000013 [ 26.036634] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000fdfffffd [ 26.043875] RDX: 0000000000000004 RSI: 0000000000000000 RDI: 0000000000000000 [ 2