[....] Starting enhanced syslogd: rsyslogd[ 12.092250] audit: type=1400 audit(1515561704.079:5): avc: denied { syslog } for pid=3347 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: [ 18.551906] audit: type=1400 audit(1515561710.539:6): avc: denied { map } for pid=3485 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 '10.128.15.218' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 24.756062] audit: type=1400 audit(1515561716.743:7): avc: denied { map } for pid=3500 comm="syzkaller073161" path="/root/syzkaller073161582" 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 [ 24.837420] [ 24.839075] ====================================================== [ 24.844065] audit: type=1400 audit(1515561716.824:8): avc: denied { map } for pid=3500 comm="syzkaller073161" path="/dev/ashmem" dev="devtmpfs" ino=1082 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 24.870046] WARNING: possible circular locking dependency detected [ 24.876333] 4.15.0-rc7-next-20180109+ #92 Not tainted [ 24.881483] ------------------------------------------------------ [ 24.887765] syzkaller073161/3500 is trying to acquire lock: [ 24.893440] (&sb->s_type->i_mutex_key#11){++++}, at: [<000000002d2f453b>] shmem_file_llseek+0xef/0x240 [ 24.902970] [ 24.902970] but task is already holding lock: [ 24.908906] (ashmem_mutex){+.+.}, at: [<000000005b81b4fc>] ashmem_llseek+0x56/0x1f0 [ 24.916763] [ 24.916763] which lock already depends on the new lock. [ 24.916763] [ 24.925577] [ 24.925577] the existing dependency chain (in reverse order) is: [ 24.933163] [ 24.933163] -> #2 (ashmem_mutex){+.+.}: [ 24.938591] __mutex_lock+0x16f/0x1a80 [ 24.942967] mutex_lock_nested+0x16/0x20 [ 24.947514] ashmem_mmap+0x53/0x410 [ 24.951665] mmap_region+0xa99/0x15a0 [ 24.955966] do_mmap+0x73c/0xf70 [ 24.959825] vm_mmap_pgoff+0x1de/0x280 [ 24.964212] SyS_mmap_pgoff+0x462/0x5f0 [ 24.968685] SyS_mmap+0x16/0x20 [ 24.972454] entry_SYSCALL_64_fastpath+0x23/0x9a [ 24.977706] [ 24.977706] -> #1 (&mm->mmap_sem){++++}: [ 24.983226] __might_fault+0x13a/0x1d0 [ 24.987605] _copy_to_user+0x2c/0xc0 [ 24.991810] filldir+0x1a7/0x320 [ 24.995674] dcache_readdir+0x12d/0x5e0 [ 25.000140] iterate_dir+0x1ca/0x530 [ 25.004342] SyS_getdents+0x225/0x450 [ 25.008632] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.013875] [ 25.013875] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.020609] lock_acquire+0x1d5/0x580 [ 25.024897] down_write+0x87/0x120 [ 25.028924] shmem_file_llseek+0xef/0x240 [ 25.033563] vfs_llseek+0xa2/0xd0 [ 25.037503] ashmem_llseek+0xe7/0x1f0 [ 25.041790] SyS_lseek+0xeb/0x170 [ 25.045732] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.050972] [ 25.050972] other info that might help us debug this: [ 25.050972] [ 25.059089] Chain exists of: [ 25.059089] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.059089] [ 25.070592] Possible unsafe locking scenario: [ 25.070592] [ 25.076615] CPU0 CPU1 [ 25.081250] ---- ---- [ 25.085884] lock(ashmem_mutex); [ 25.089304] lock(&mm->mmap_sem); [ 25.095325] lock(ashmem_mutex); [ 25.101262] lock(&sb->s_type->i_mutex_key#11); [ 25.105985] [ 25.105985] *** DEADLOCK *** [ 25.105985] [ 25.112032] 1 lock held by syzkaller073161/3500: [ 25.116751] #0: (ashmem_mutex){+.+.}, at: [<000000005b81b4fc>] ashmem_llseek+0x56/0x1f0 [ 25.125066] [ 25.125066] stack backtrace: [ 25.129533] CPU: 0 PID: 3500 Comm: syzkaller073161 Not tainted 4.15.0-rc7-next-20180109+ #92 [ 25.138074] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.148214] Call Trace: [ 25.150783] dump_stack+0x194/0x257 [ 25.154376] ? arch_local_irq_restore+0x53/0x53 [ 25.159015] print_circular_bug.isra.37+0x2cd/0x2dc [ 25.163997] ? save_trace+0xe0/0x2b0 [ 25.167679] __lock_acquire+0x30a8/0x3e00 [ 25.171827] ? lock_downgrade+0x980/0x980 [ 25.175943] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 25.180755] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.185914] ? ashmem_llseek+0x56/0x1f0 [ 25.189856] ? lock_release+0xa40/0xa40 [ 25.193795] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.199649] ? vma_set_page_prot+0x16b/0x230 [ 25.204027] ? rcu_note_context_switch+0x710/0x710 [ 25.208923] ? vma_wants_writenotify+0x3b0/0x3b0 [ 25.213649] ? __might_sleep+0x95/0x190 [ 25.217590] ? ashmem_llseek+0x56/0x1f0 [ 25.221532] ? __mutex_lock+0x16f/0x1a80 [ 25.225573] ? ashmem_llseek+0x56/0x1f0 [ 25.229514] ? ashmem_llseek+0x56/0x1f0 [ 25.233456] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.238270] ? vm_mmap_pgoff+0x1ed/0x280 [ 25.242300] ? selinux_mmap_addr+0x1f/0xf0 [ 25.246504] ? userfaultfd_unmap_complete+0x327/0x510 [ 25.251665] ? get_unmapped_area+0x265/0x300 [ 25.256041] lock_acquire+0x1d5/0x580 [ 25.259810] ? lock_acquire+0x1d5/0x580 [ 25.263761] ? shmem_file_llseek+0xef/0x240 [ 25.268054] ? lock_release+0xa40/0xa40 [ 25.271997] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.277864] ? rcu_note_context_switch+0x710/0x710 [ 25.282760] ? __fget_light+0x297/0x380 [ 25.286701] ? __might_sleep+0x95/0x190 [ 25.290645] down_write+0x87/0x120 [ 25.294154] ? shmem_file_llseek+0xef/0x240 [ 25.298444] ? down_read+0x150/0x150 [ 25.302128] ? selinux_capable+0x40/0x40 [ 25.306155] shmem_file_llseek+0xef/0x240 [ 25.310270] ? shmem_free_swap+0x80/0x80 [ 25.314302] vfs_llseek+0xa2/0xd0 [ 25.317728] ashmem_llseek+0xe7/0x1f0 [ 25.321497] ? ashmem_read_iter+0x230/0x230 [ 25.325786] SyS_lseek+0xeb/0x170 [ 25.329206] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.333927] RIP: 0033:0x444aa9 [ 25.337082] RSP: 002b:00007ffdaa408b3