[....] Starting enhanced syslogd: rsyslogd[ 12.864167] audit: type=1400 audit(1516099674.504:5): avc: denied { syslog } for pid=3518 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: [ 19.000346] audit: type=1400 audit(1516099680.639:6): avc: denied { map } for pid=3658 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 '10.128.15.229' (ECDSA) to the list of known hosts. executing program [ 25.251252] audit: type=1400 audit(1516099686.891:7): avc: denied { map } for pid=3672 comm="syzkaller770711" path="/root/syzkaller770711384" dev="sda1" ino=16481 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=unconfined_u:object_r:user_home_t:s0 tclass=file permissive=1 [ 25.255170] [ 25.277230] audit: type=1400 audit(1516099686.894:8): avc: denied { map } for pid=3672 comm="syzkaller770711" path="/dev/ashmem" dev="devtmpfs" ino=1080 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 25.278787] ====================================================== [ 25.278789] WARNING: possible circular locking dependency detected [ 25.278795] 4.15.0-rc8-next-20180116+ #98 Not tainted [ 25.278796] ------------------------------------------------------ [ 25.278799] syzkaller770711/3672 is trying to acquire lock: [ 25.278803] (&sb->s_type->i_mutex_key#11){++++}, at: [<00000000bf751abc>] shmem_file_llseek+0xef/0x240 [ 25.342751] [ 25.342751] but task is already holding lock: [ 25.348692] (ashmem_mutex){+.+.}, at: [<0000000055807ddc>] ashmem_llseek+0x56/0x1f0 [ 25.356551] [ 25.356551] which lock already depends on the new lock. [ 25.356551] [ 25.364835] [ 25.364835] the existing dependency chain (in reverse order) is: [ 25.372426] [ 25.372426] -> #2 (ashmem_mutex){+.+.}: [ 25.377861] __mutex_lock+0x16f/0x1a80 [ 25.382240] mutex_lock_nested+0x16/0x20 [ 25.386796] ashmem_mmap+0x53/0x410 [ 25.390916] mmap_region+0xa99/0x15a0 [ 25.395208] do_mmap+0x73c/0xf70 [ 25.399072] vm_mmap_pgoff+0x1de/0x280 [ 25.403456] SyS_mmap_pgoff+0x462/0x5f0 [ 25.407925] SyS_mmap+0x16/0x20 [ 25.411702] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.416949] [ 25.416949] -> #1 (&mm->mmap_sem){++++}: [ 25.422466] __might_fault+0x13a/0x1d0 [ 25.426847] _copy_to_user+0x2c/0xc0 [ 25.431059] filldir+0x1a7/0x320 [ 25.434923] dcache_readdir+0x12d/0x5e0 [ 25.439388] iterate_dir+0x1ca/0x530 [ 25.443594] SyS_getdents+0x225/0x450 [ 25.447887] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.453131] [ 25.453131] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.459864] lock_acquire+0x1d5/0x580 [ 25.464157] down_write+0x87/0x120 [ 25.468204] shmem_file_llseek+0xef/0x240 [ 25.472848] vfs_llseek+0xa2/0xd0 [ 25.476795] ashmem_llseek+0xe7/0x1f0 [ 25.481087] SyS_lseek+0xeb/0x170 [ 25.485035] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.490278] [ 25.490278] other info that might help us debug this: [ 25.490278] [ 25.498404] Chain exists of: [ 25.498404] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.498404] [ 25.509914] Possible unsafe locking scenario: [ 25.509914] [ 25.515947] CPU0 CPU1 [ 25.520584] ---- ---- [ 25.525222] lock(ashmem_mutex); [ 25.528661] lock(&mm->mmap_sem); [ 25.534702] lock(ashmem_mutex); [ 25.540648] lock(&sb->s_type->i_mutex_key#11); [ 25.545377] [ 25.545377] *** DEADLOCK *** [ 25.545377] [ 25.551409] 1 lock held by syzkaller770711/3672: [ 25.556132] #0: (ashmem_mutex){+.+.}, at: [<0000000055807ddc>] ashmem_llseek+0x56/0x1f0 [ 25.564445] [ 25.564445] stack backtrace: [ 25.568930] CPU: 0 PID: 3672 Comm: syzkaller770711 Not tainted 4.15.0-rc8-next-20180116+ #98 [ 25.577495] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.586824] Call Trace: [ 25.589410] dump_stack+0x194/0x257 [ 25.593012] ? arch_local_irq_restore+0x53/0x53 [ 25.597662] print_circular_bug.isra.37+0x2cd/0x2dc [ 25.602654] ? save_trace+0xe0/0x2b0 [ 25.606341] __lock_acquire+0x30a8/0x3e00 [ 25.610463] ? lock_downgrade+0x980/0x980 [ 25.614586] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 25.619404] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.624570] ? ashmem_llseek+0x56/0x1f0 [ 25.628522] ? lock_release+0xa40/0xa40 [ 25.632479] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.638344] ? vma_set_page_prot+0x16b/0x230 [ 25.642730] ? rcu_note_context_switch+0x710/0x710 [ 25.647634] ? vma_wants_writenotify+0x3b0/0x3b0 [ 25.652374] ? __might_sleep+0x95/0x190 [ 25.656324] ? ashmem_llseek+0x56/0x1f0 [ 25.660274] ? __mutex_lock+0x16f/0x1a80 [ 25.664309] ? ashmem_llseek+0x56/0x1f0 [ 25.668255] ? ashmem_llseek+0x56/0x1f0 [ 25.672206] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.677021] ? vm_mmap_pgoff+0x1ed/0x280 [ 25.681068] ? selinux_mmap_addr+0x1f/0xf0 [ 25.685292] ? userfaultfd_unmap_complete+0x327/0x510 [ 25.690456] ? get_unmapped_area+0x265/0x300 [ 25.694840] lock_acquire+0x1d5/0x580 [ 25.698614] ? lock_acquire+0x1d5/0x580 [ 25.702564] ? shmem_file_llseek+0xef/0x240 [ 25.706863] ? lock_release+0xa40/0xa40 [ 25.710821] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.716680] ? rcu_note_context_switch+0x710/0x710 [ 25.721597] ? __fget_light+0x297/0x380 [ 25.725544] ? __might_sleep+0x95/0x190 [ 25.729493] down_write+0x87/0x120 [ 25.733009] ? shmem_file_llseek+0xef/0x240 [ 25.737304] ? down_read+0x150/0x150 [ 25.740991] ? selinux_capable+0x40/0x40 [ 25.745026] shmem_file_llseek+0xef/0x240 [ 25.749160] ? shmem_free_swap+0x80/0x80 [ 25.753204] vfs_llseek+0xa2/0xd0 [ 25.756632] ashmem_llseek+0xe7/0x1f0 [ 25.760420] ? ashmem_read_iter+0x230/0x230 [ 25.764713] SyS_lseek+0xeb/0x170 [ 25.768140] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.772866] RIP: 0033:0x43fcd9 [ 25.776032] RSP: 002b:00007ffcb0b3fe88 EFLAGS: 00000217 ORIG_RAX: 0000000000000008 [ 25.783710] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fcd9 [ 25.790951] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000003 [ 25.798204] RBP: 00000000006ca018 R08: 0000000000000000 R09: