[....] Starting enhanced syslogd: rsyslogd[ 13.081131] audit: type=1400 audit(1515530810.359:5): avc: denied { syslog } for pid=3349 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: [ 18.479803] audit: type=1400 audit(1515530815.758:6): 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 '10.128.0.17' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 24.766145] audit: type=1400 audit(1515530822.044:7): avc: denied { map } for pid=3503 comm="syzkaller033589" path="/root/syzkaller033589812" 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 [ 24.886810] [ 24.888464] ====================================================== [ 24.889206] audit: type=1400 audit(1515530822.164:8): avc: denied { map } for pid=3503 comm="syzkaller033589" path="/dev/ashmem" dev="devtmpfs" ino=1164 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 24.919442] WARNING: possible circular locking dependency detected [ 24.925729] 4.15.0-rc7-next-20180109+ #92 Not tainted [ 24.930881] ------------------------------------------------------ [ 24.937164] syzkaller033589/3503 is trying to acquire lock: [ 24.942839] (&sb->s_type->i_mutex_key#11){++++}, at: [<0000000083e5128b>] shmem_file_llseek+0xef/0x240 [ 24.952349] [ 24.952349] but task is already holding lock: [ 24.958284] (ashmem_mutex){+.+.}, at: [<00000000de2ea3b6>] ashmem_llseek+0x56/0x1f0 [ 24.966138] [ 24.966138] which lock already depends on the new lock. [ 24.966138] [ 24.974420] [ 24.974420] the existing dependency chain (in reverse order) is: [ 24.982015] [ 24.982015] -> #2 (ashmem_mutex){+.+.}: [ 24.987446] __mutex_lock+0x16f/0x1a80 [ 24.991819] mutex_lock_nested+0x16/0x20 [ 24.996366] ashmem_mmap+0x53/0x410 [ 25.000480] mmap_region+0xa99/0x15a0 [ 25.004769] do_mmap+0x73c/0xf70 [ 25.008621] vm_mmap_pgoff+0x1de/0x280 [ 25.012993] SyS_mmap_pgoff+0x462/0x5f0 [ 25.017459] SyS_mmap+0x16/0x20 [ 25.021226] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.026466] [ 25.026466] -> #1 (&mm->mmap_sem){++++}: [ 25.031976] __might_fault+0x13a/0x1d0 [ 25.036358] _copy_to_user+0x2c/0xc0 [ 25.040559] filldir+0x1a7/0x320 [ 25.044417] dcache_readdir+0x12d/0x5e0 [ 25.048876] iterate_dir+0x1ca/0x530 [ 25.053077] SyS_getdents+0x225/0x450 [ 25.057362] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.062601] [ 25.062601] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.069327] lock_acquire+0x1d5/0x580 [ 25.073616] down_write+0x87/0x120 [ 25.077642] shmem_file_llseek+0xef/0x240 [ 25.082277] vfs_llseek+0xa2/0xd0 [ 25.086218] ashmem_llseek+0xe7/0x1f0 [ 25.090503] SyS_lseek+0xeb/0x170 [ 25.094443] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.099681] [ 25.099681] other info that might help us debug this: [ 25.099681] [ 25.107789] Chain exists of: [ 25.107789] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.107789] [ 25.119297] Possible unsafe locking scenario: [ 25.119297] [ 25.125323] CPU0 CPU1 [ 25.129958] ---- ---- [ 25.134595] lock(ashmem_mutex); [ 25.138019] lock(&mm->mmap_sem); [ 25.144046] lock(ashmem_mutex); [ 25.149987] lock(&sb->s_type->i_mutex_key#11); [ 25.154713] [ 25.154713] *** DEADLOCK *** [ 25.154713] [ 25.160741] 1 lock held by syzkaller033589/3503: [ 25.165461] #0: (ashmem_mutex){+.+.}, at: [<00000000de2ea3b6>] ashmem_llseek+0x56/0x1f0 [ 25.173750] [ 25.173750] stack backtrace: [ 25.178215] CPU: 1 PID: 3503 Comm: syzkaller033589 Not tainted 4.15.0-rc7-next-20180109+ #92 [ 25.186769] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.196098] Call Trace: [ 25.198668] dump_stack+0x194/0x257 [ 25.202273] ? arch_local_irq_restore+0x53/0x53 [ 25.206925] print_circular_bug.isra.37+0x2cd/0x2dc [ 25.211911] ? save_trace+0xe0/0x2b0 [ 25.215593] __lock_acquire+0x30a8/0x3e00 [ 25.219707] ? lock_downgrade+0x980/0x980 [ 25.223835] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 25.228658] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.233818] ? ashmem_llseek+0x56/0x1f0 [ 25.237760] ? lock_release+0xa40/0xa40 [ 25.241703] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.247565] ? vma_set_page_prot+0x16b/0x230 [ 25.251961] ? rcu_note_context_switch+0x710/0x710 [ 25.256885] ? vma_wants_writenotify+0x3b0/0x3b0 [ 25.261633] ? __might_sleep+0x95/0x190 [ 25.265579] ? ashmem_llseek+0x56/0x1f0 [ 25.269523] ? __mutex_lock+0x16f/0x1a80 [ 25.273566] ? ashmem_llseek+0x56/0x1f0 [ 25.277507] ? ashmem_llseek+0x56/0x1f0 [ 25.281456] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.286266] ? vm_mmap_pgoff+0x1ed/0x280 [ 25.290294] ? selinux_mmap_addr+0x1f/0xf0 [ 25.294494] ? userfaultfd_unmap_complete+0x327/0x510 [ 25.299650] ? get_unmapped_area+0x265/0x300 [ 25.304027] lock_acquire+0x1d5/0x580 [ 25.307793] ? lock_acquire+0x1d5/0x580 [ 25.311736] ? shmem_file_llseek+0xef/0x240 [ 25.316031] ? lock_release+0xa40/0xa40 [ 25.319974] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.325842] ? rcu_note_context_switch+0x710/0x710 [ 25.330744] ? __fget_light+0x297/0x380 [ 25.334693] ? __might_sleep+0x95/0x190 [ 25.338633] down_write+0x87/0x120 [ 25.342146] ? shmem_file_llseek+0xef/0x240 [ 25.346433] ? down_read+0x150/0x150 [ 25.350125] ? selinux_capable+0x40/0x40 [ 25.354152] shmem_file_llseek+0xef/0x240 [ 25.358273] ? shmem_free_swap+0x80/0x80 [ 25.362311] vfs_llseek+0xa2/0xd0 [ 25.365731] ashmem_llseek+0xe7/0x1f0 [ 25.369500] ? ashmem_read_iter+0x230/0x230 [ 25.373787] SyS_lseek+0xeb/0x170 [ 25.377206] entry_SYSCALL_64_fastpath+0x23/0x9a [ 25.381928] RIP: 0033:0x444aa9 [ 25.385085] RSP: 002b:00007fff2e769118 EFLAG