[....] Starting enhanced syslogd: rsyslogd[ 12.080741] audit: type=1400 audit(1515534778.701:5): avc: denied { syslog } for pid=3351 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: [ 17.103615] audit: type=1400 audit(1515534783.724:6): avc: denied { map } for pid=3490 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 '10.128.0.59' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 25.310514] audit: type=1400 audit(1515534791.931:7): avc: denied { map } for pid=3505 comm="syzkaller028429" path="/root/syzkaller028429306" 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 executing program [ 25.430791] [ 25.432448] ====================================================== [ 25.432588] audit: type=1400 audit(1515534792.051:8): avc: denied { map } for pid=3505 comm="syzkaller028429" path="/dev/ashmem" dev="devtmpfs" ino=8988 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 25.464164] WARNING: possible circular locking dependency detected [ 25.471145] 4.15.0-rc6-mm1+ #52 Not tainted [ 25.475429] ------------------------------------------------------ [ 25.481709] syzkaller028429/3505 is trying to acquire lock: [ 25.487387] (&sb->s_type->i_mutex_key#11){++++}, at: [<000000000cf46393>] shmem_file_llseek+0xef/0x240 [ 25.496898] [ 25.496898] but task is already holding lock: [ 25.502854] (ashmem_mutex){+.+.}, at: [<00000000fc8f297d>] ashmem_llseek+0x56/0x1f0 [ 25.512184] [ 25.512184] which lock already depends on the new lock. [ 25.512184] [ 25.520462] [ 25.520462] the existing dependency chain (in reverse order) is: [ 25.528053] [ 25.528053] -> #2 (ashmem_mutex){+.+.}: [ 25.533480] __mutex_lock+0x16f/0x1a80 [ 25.537852] mutex_lock_nested+0x16/0x20 [ 25.542662] ashmem_mmap+0x53/0x410 [ 25.546776] mmap_region+0xa99/0x15a0 [ 25.551062] do_mmap+0x73c/0xf70 [ 25.554914] vm_mmap_pgoff+0x1de/0x280 [ 25.559288] SyS_mmap_pgoff+0x462/0x5f0 [ 25.563747] SyS_mmap+0x16/0x20 [ 25.567515] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.572761] [ 25.572761] -> #1 (&mm->mmap_sem){++++}: [ 25.578273] __might_fault+0x13a/0x1d0 [ 25.582648] _copy_to_user+0x2c/0xc0 [ 25.586849] filldir+0x1a7/0x320 [ 25.590701] dcache_readdir+0x12d/0x5e0 [ 25.595170] iterate_dir+0x1ca/0x530 [ 25.599370] SyS_getdents+0x225/0x450 [ 25.603661] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.608901] [ 25.608901] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.615632] lock_acquire+0x1d5/0x580 [ 25.619919] down_write+0x87/0x120 [ 25.623944] shmem_file_llseek+0xef/0x240 [ 25.628579] vfs_llseek+0xa2/0xd0 [ 25.632520] ashmem_llseek+0xe7/0x1f0 [ 25.636806] SyS_lseek+0xeb/0x170 [ 25.640931] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.648698] [ 25.648698] other info that might help us debug this: [ 25.648698] [ 25.657500] Chain exists of: [ 25.657500] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.657500] [ 25.669002] Possible unsafe locking scenario: [ 25.669002] [ 25.675030] CPU0 CPU1 [ 25.679660] ---- ---- [ 25.684295] lock(ashmem_mutex); [ 25.687720] lock(&mm->mmap_sem); [ 25.693741] lock(ashmem_mutex); [ 25.699675] lock(&sb->s_type->i_mutex_key#11); [ 25.704401] [ 25.704401] *** DEADLOCK *** [ 25.704401] [ 25.710696] 1 lock held by syzkaller028429/3505: [ 25.715414] #0: (ashmem_mutex){+.+.}, at: [<00000000fc8f297d>] ashmem_llseek+0x56/0x1f0 [ 25.723704] [ 25.723704] stack backtrace: [ 25.728168] CPU: 0 PID: 3505 Comm: syzkaller028429 Not tainted 4.15.0-rc6-mm1+ #52 [ 25.735838] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.745158] Call Trace: [ 25.747717] dump_stack+0x194/0x257 [ 25.751311] ? arch_local_irq_restore+0x53/0x53 [ 25.755958] print_circular_bug.isra.37+0x2cd/0x2dc [ 25.760947] ? save_trace+0xe0/0x2b0 [ 25.764636] __lock_acquire+0x30a8/0x3e00 [ 25.768748] ? lock_downgrade+0x980/0x980 [ 25.772863] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 25.777677] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.782835] ? ashmem_llseek+0x56/0x1f0 [ 25.786776] ? lock_release+0xa40/0xa40 [ 25.790717] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.796915] ? vma_set_page_prot+0x16b/0x230 [ 25.801550] ? rcu_note_context_switch+0x710/0x710 [ 25.806444] ? vma_wants_writenotify+0x3b0/0x3b0 [ 25.811166] ? __might_sleep+0x95/0x190 [ 25.815109] ? ashmem_llseek+0x56/0x1f0 [ 25.819053] ? __mutex_lock+0x16f/0x1a80 [ 25.823085] ? ashmem_llseek+0x56/0x1f0 [ 25.827043] ? ashmem_llseek+0x56/0x1f0 [ 25.830995] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.835829] ? vm_mmap_pgoff+0x1ed/0x280 [ 25.841074] ? selinux_mmap_addr+0x1f/0xf0 [ 25.845277] ? userfaultfd_unmap_complete+0x327/0x510 [ 25.850445] ? get_unmapped_area+0x265/0x300 [ 25.854827] lock_acquire+0x1d5/0x580 [ 25.858593] ? lock_acquire+0x1d5/0x580 [ 25.862535] ? shmem_file_llseek+0xef/0x240 [ 25.866823] ? lock_release+0xa40/0xa40 [ 25.870762] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.876614] ? rcu_note_context_switch+0x710/0x710 [ 25.881508] ? __fget_light+0x297/0x380 [ 25.885454] ? __might_sleep+0x95/0x190 [ 25.889404] down_write+0x87/0x120 [ 25.892910] ? shmem_file_llseek+0xef/0x240 [ 25.897198] ? down_read+0x150/0x150 [ 25.901576] ? selinux_capable+0x40/0x40 [ 25.905607] shmem_file_llseek+0xef/0x240 [ 25.909721] ? shmem_free_swap+0x80/0x80 [ 25.913751] vfs_llseek+0xa2/0xd0 [ 25.917171] ashmem_llseek+0xe7/0x1f0 [ 25.920941] ? ashmem_read_iter+0x230/0x230 [ 25.925232] SyS_lseek+0xeb/0x170 [ 25.928653] entry_SYSCALL_64_fastpath+0x23/0x9