[....] Starting enhanced syslogd: rsyslogd[ 11.984502] audit: type=1400 audit(1515563109.215:5): 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 mcstransd: [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] 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: [ 18.165261] audit: type=1400 audit(1515563115.396:6): avc: denied { map } for pid=3489 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 '10.128.0.34' (ECDSA) to the list of known hosts. executing program executing program executing program [ 24.346283] audit: type=1400 audit(1515563121.577:7): avc: denied { map } for pid=3503 comm="syzkaller912863" path="/root/syzkaller912863470" 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 executing program [ 24.372913] audit: type=1400 audit(1515563121.577:8): avc: denied { map } for pid=3503 comm="syzkaller912863" path="/dev/ashmem" dev="devtmpfs" ino=8907 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 24.418767] [ 24.420442] ====================================================== [ 24.426723] WARNING: possible circular locking dependency detected [ 24.433007] 4.15.0-rc6-mm1+ #52 Not tainted [ 24.437289] ------------------------------------------------------ [ 24.443577] syzkaller912863/3505 is trying to acquire lock: [ 24.449275] (&sb->s_type->i_mutex_key#11){++++}, at: [<00000000ed978365>] shmem_file_llseek+0xef/0x240 [ 24.458799] [ 24.458799] but task is already holding lock: executing program [ 24.464736] (ashmem_mutex){+.+.}, at: [<00000000a3a4cb40>] ashmem_llseek+0x56/0x1f0 [ 24.473381] [ 24.473381] which lock already depends on the new lock. [ 24.473381] [ 24.481682] [ 24.481682] the existing dependency chain (in reverse order) is: [ 24.489267] [ 24.489267] -> #2 (ashmem_mutex){+.+.}: [ 24.494703] __mutex_lock+0x16f/0x1a80 [ 24.499077] mutex_lock_nested+0x16/0x20 [ 24.503623] ashmem_mmap+0x53/0x410 [ 24.507736] mmap_region+0xa99/0x15a0 [ 24.512033] do_mmap+0x73c/0xf70 [ 24.517369] vm_mmap_pgoff+0x1de/0x280 [ 24.523312] SyS_mmap_pgoff+0x462/0x5f0 [ 24.529174] SyS_mmap+0x16/0x20 [ 24.533642] entry_SYSCALL_64_fastpath+0x23/0x9a [ 24.538888] [ 24.538888] -> #1 (&mm->mmap_sem){++++}: [ 24.544397] __might_fault+0x13a/0x1d0 [ 24.548775] _copy_to_user+0x2c/0xc0 [ 24.552975] filldir+0x1a7/0x320 [ 24.556827] dcache_readdir+0x12d/0x5e0 [ 24.561286] iterate_dir+0x1ca/0x530 [ 24.565485] SyS_getdents+0x225/0x450 [ 24.569768] entry_SYSCALL_64_fastpath+0x23/0x9a [ 24.575011] [ 24.575011] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 24.581747] lock_acquire+0x1d5/0x580 [ 24.586034] down_write+0x87/0x120 [ 24.590066] shmem_file_llseek+0xef/0x240 [ 24.594709] vfs_llseek+0xa2/0xd0 [ 24.600021] ashmem_llseek+0xe7/0x1f0 [ 24.605449] SyS_lseek+0xeb/0x170 [ 24.609398] entry_SYSCALL_64_fastpath+0x23/0x9a [ 24.614651] [ 24.614651] other info that might help us debug this: [ 24.614651] [ 24.622764] Chain exists of: [ 24.622764] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 24.622764] [ 24.634284] Possible unsafe locking scenario: [ 24.634284] [ 24.640315] CPU0 CPU1 [ 24.644953] ---- ---- [ 24.649584] lock(ashmem_mutex); [ 24.653003] lock(&mm->mmap_sem); [ 24.659032] lock(ashmem_mutex); [ 24.664977] lock(&sb->s_type->i_mutex_key#11); [ 24.669696] [ 24.669696] *** DEADLOCK *** [ 24.669696] [ 24.675721] 1 lock held by syzkaller912863/3505: [ 24.680449] #0: (ashmem_mutex){+.+.}, at: [<00000000a3a4cb40>] ashmem_llseek+0x56/0x1f0 [ 24.688747] [ 24.688747] stack backtrace: [ 24.693218] CPU: 0 PID: 3505 Comm: syzkaller912863 Not tainted 4.15.0-rc6-mm1+ #52 [ 24.700897] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 24.710215] Call Trace: [ 24.712776] dump_stack+0x194/0x257 [ 24.716376] ? arch_local_irq_restore+0x53/0x53 [ 24.723096] print_circular_bug.isra.37+0x2cd/0x2dc [ 24.729643] ? save_trace+0xe0/0x2b0 [ 24.733330] __lock_acquire+0x30a8/0x3e00 [ 24.737446] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 24.742607] ? ashmem_llseek+0x56/0x1f0 [ 24.746560] ? lock_release+0xa40/0xa40 [ 24.750501] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 24.756362] ? do_futex+0x86f/0x22a0 [ 24.760050] ? vma_set_page_prot+0x16b/0x230 [ 24.764423] ? rcu_note_context_switch+0x710/0x710 [ 24.769319] ? __might_sleep+0x95/0x190 [ 24.773261] ? ashmem_llseek+0x56/0x1f0 [ 24.777207] ? __mutex_lock+0x16f/0x1a80 [ 24.782015] ? ashmem_llseek+0x56/0x1f0 [ 24.785954] ? lock_downgrade+0x980/0x980 [ 24.790067] ? ashmem_llseek+0x56/0x1f0 [ 24.794014] ? lock_release+0xa40/0xa40 [ 24.797966] ? mutex_lock_io_nested+0x1900/0x1900 [ 24.802782] ? __lock_is_held+0xb6/0x140 [ 24.806820] ? __fget+0x35c/0x570 [ 24.810241] ? userfaultfd_unmap_complete+0x327/0x510 [ 24.815400] lock_acquire+0x1d5/0x580 [ 24.819164] ? lock_acquire+0x1d5/0x580 [ 24.823116] ? shmem_file_llseek+0xef/0x240 [ 24.827412] ? lock_release+0xa40/0xa40 [ 24.831353] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 24.837213] ? rcu_note_context_switch+0x710/0x710 [ 24.842108] ? __fget_light+0x297/0x380 [ 24.846046] ? __might_sleep+0x95/0x190 [ 24.849986] down_write+0x87/0x120 [ 24.853507] ? shmem_file_llseek+0xef/0x240 [ 24.857804] ? down_read+0x150/0x150 [ 24.861494] shmem_file_llseek+0xef/0x240 [ 24.865614] ? shmem_free_swap+0x80/0x80 [ 24.869643] vfs_llseek+0xa2/0xd0 [ 24.873074] ashmem_llseek+0xe7/0x1f0 [ 24.876842] ? ashmem_read_iter+0x230/0x230 [ 24.881137] SyS_lseek+0xeb/0x170 [ 24.884555] entry_SYSCALL_64_fastpath+0x23/0x9a [ 24.889278] RIP: 0033:0x445519 [ 24.892442] RSP: 002b:00007f8227c45da8 EFLAGS: 00000293 ORIG_RAX: 0000000000000008 [ 24.900115] RAX: ffffffffffffffda RBX: 00000000006dac3c RCX: 0000000000445519 [ 24.907364] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 000000000000000b executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program [ 24.914611] RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 [ 24.922635] R10: 0000000000000000 R11: 0000000000000293 R12: 00000000006dac38 [ 24.929884] R13: 6873612f7665642f R14: 00007f8227c469c0 R15: 0000000000000005 executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program