[....] Starting enhanced syslogd: rsyslogd[ 12.136253] audit: type=1400 audit(1515565175.124:5): 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 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: [ 16.856643] audit: type=1400 audit(1515565179.845:6): avc: denied { map } for pid=3488 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 '10.128.0.37' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 23.053404] audit: type=1400 audit(1515565186.042:7): avc: denied { map } for pid=3502 comm="syzkaller690198" path="/root/syzkaller690198281" 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 [ 23.163822] [ 23.165479] ====================================================== [ 23.168071] audit: type=1400 audit(1515565186.152:8): avc: denied { map } for pid=3502 comm="syzkaller690198" path="/dev/ashmem" dev="devtmpfs" ino=108 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 23.197763] WARNING: possible circular locking dependency detected [ 23.204063] 4.15.0-rc7-next-20180110+ #93 Not tainted [ 23.209212] ------------------------------------------------------ [ 23.215492] syzkaller690198/3502 is trying to acquire lock: [ 23.221163] (&sb->s_type->i_mutex_key#11){++++}, at: [<00000000ad800946>] shmem_file_llseek+0xef/0x240 [ 23.230678] [ 23.230678] but task is already holding lock: [ 23.236966] (ashmem_mutex){+.+.}, at: [<00000000f7eaf876>] ashmem_llseek+0x56/0x1f0 [ 23.246302] [ 23.246302] which lock already depends on the new lock. [ 23.246302] [ 23.254582] [ 23.254582] the existing dependency chain (in reverse order) is: [ 23.262166] [ 23.262166] -> #2 (ashmem_mutex){+.+.}: [ 23.267589] __mutex_lock+0x16f/0x1a80 [ 23.271961] mutex_lock_nested+0x16/0x20 [ 23.276507] ashmem_mmap+0x53/0x410 [ 23.280618] mmap_region+0xa99/0x15a0 [ 23.284903] do_mmap+0x73c/0xf70 [ 23.288755] vm_mmap_pgoff+0x1de/0x280 [ 23.293133] SyS_mmap_pgoff+0x462/0x5f0 [ 23.297593] SyS_mmap+0x16/0x20 [ 23.301363] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 23.306605] [ 23.306605] -> #1 (&mm->mmap_sem){++++}: [ 23.312116] __might_fault+0x13a/0x1d0 [ 23.317619] _copy_to_user+0x2c/0xc0 [ 23.323310] filldir+0x1a7/0x320 [ 23.327168] dcache_readdir+0x12d/0x5e0 [ 23.331628] iterate_dir+0x1ca/0x530 [ 23.335827] SyS_getdents+0x225/0x450 [ 23.340113] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 23.345352] [ 23.345352] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 23.352079] lock_acquire+0x1d5/0x580 [ 23.356365] down_write+0x87/0x120 [ 23.360391] shmem_file_llseek+0xef/0x240 [ 23.365029] vfs_llseek+0xa2/0xd0 [ 23.368973] ashmem_llseek+0xe7/0x1f0 [ 23.373259] SyS_lseek+0xeb/0x170 [ 23.377199] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 23.382438] [ 23.382438] other info that might help us debug this: [ 23.382438] [ 23.390543] Chain exists of: [ 23.390543] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 23.390543] [ 23.402043] Possible unsafe locking scenario: [ 23.402043] [ 23.408068] CPU0 CPU1 [ 23.412703] ---- ---- [ 23.417331] lock(ashmem_mutex); [ 23.420755] lock(&mm->mmap_sem); [ 23.426775] lock(ashmem_mutex); [ 23.432710] lock(&sb->s_type->i_mutex_key#11); [ 23.437432] [ 23.437432] *** DEADLOCK *** [ 23.437432] [ 23.443466] 1 lock held by syzkaller690198/3502: [ 23.448186] #0: (ashmem_mutex){+.+.}, at: [<00000000f7eaf876>] ashmem_llseek+0x56/0x1f0 [ 23.456917] [ 23.456917] stack backtrace: [ 23.461380] CPU: 0 PID: 3502 Comm: syzkaller690198 Not tainted 4.15.0-rc7-next-20180110+ #93 [ 23.469916] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 23.479240] Call Trace: [ 23.481797] dump_stack+0x194/0x257 [ 23.485391] ? arch_local_irq_restore+0x53/0x53 [ 23.490362] print_circular_bug.isra.37+0x2cd/0x2dc [ 23.495341] ? save_trace+0xe0/0x2b0 [ 23.499048] __lock_acquire+0x30a8/0x3e00 [ 23.503163] ? lock_downgrade+0x980/0x980 [ 23.507280] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 23.512090] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 23.517244] ? ashmem_llseek+0x56/0x1f0 [ 23.521183] ? lock_release+0xa40/0xa40 [ 23.525127] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 23.530984] ? vma_set_page_prot+0x16b/0x230 [ 23.535626] ? rcu_note_context_switch+0x710/0x710 [ 23.540526] ? vma_wants_writenotify+0x3b0/0x3b0 [ 23.545247] ? __might_sleep+0x95/0x190 [ 23.549187] ? ashmem_llseek+0x56/0x1f0 [ 23.553213] ? __mutex_lock+0x16f/0x1a80 [ 23.557245] ? ashmem_llseek+0x56/0x1f0 [ 23.561185] ? ashmem_llseek+0x56/0x1f0 [ 23.565125] ? mutex_lock_io_nested+0x1900/0x1900 [ 23.570742] ? vm_mmap_pgoff+0x1ed/0x280 [ 23.574771] ? selinux_mmap_addr+0x1f/0xf0 [ 23.579058] ? userfaultfd_unmap_complete+0x327/0x510 [ 23.584478] ? get_unmapped_area+0x265/0x300 [ 23.588859] lock_acquire+0x1d5/0x580 [ 23.592625] ? lock_acquire+0x1d5/0x580 [ 23.596566] ? shmem_file_llseek+0xef/0x240 [ 23.600853] ? lock_release+0xa40/0xa40 [ 23.604793] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 23.610642] ? rcu_note_context_switch+0x710/0x710 [ 23.615538] ? __fget_light+0x297/0x380 [ 23.619476] ? __might_sleep+0x95/0x190 [ 23.623415] down_write+0x87/0x120 [ 23.626919] ? shmem_file_llseek+0xef/0x240 [ 23.631210] ? down_read+0x150/0x150 [ 23.634974] ? selinux_capable+0x40/0x40 [ 23.639002] shmem_file_llseek+0xef/0x240 [ 23.643128] ? shmem_free_swap+0x80/0x80 [ 23.647157] vfs_llseek+0xa2/0xd0 [ 23.650580] ashmem_llseek+0xe7/0x1f0 [ 23.654349] ? ashmem_read_iter+0x230/0x230 [ 23.658639] SyS_lseek+0xeb/0x170 [ 23.662069] entry_SYSCALL_64_fastpath+0x2