[....] Starting enhanced syslogd: rsyslogd[ 11.286214] audit: type=1400 audit(1515561072.503:5): avc: denied { syslog } for pid=3316 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: [ 16.057624] audit: type=1400 audit(1515561077.274:6): avc: denied { map } for pid=3456 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 '10.128.15.220' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 26.384043] audit: type=1400 audit(1515561087.600:7): avc: denied { map } for pid=3471 comm="syzkaller975765" path="/root/syzkaller975765455" 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 [ 26.463725] [ 26.464312] audit: type=1400 audit(1515561087.679:8): avc: denied { map } for pid=3471 comm="syzkaller975765" path="/dev/ashmem" dev="devtmpfs" ino=8934 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 26.490064] ====================================================== [ 26.496353] WARNING: possible circular locking dependency detected [ 26.502633] 4.15.0-rc7-next-20180109+ #92 Not tainted [ 26.507781] ------------------------------------------------------ [ 26.514063] syzkaller975765/3471 is trying to acquire lock: [ 26.519732] (&sb->s_type->i_mutex_key#11){++++}, at: [<00000000899618b3>] shmem_file_llseek+0xef/0x240 [ 26.529249] [ 26.529249] but task is already holding lock: [ 26.535190] (ashmem_mutex){+.+.}, at: [<000000009fc576fd>] ashmem_llseek+0x56/0x1f0 [ 26.543047] [ 26.543047] which lock already depends on the new lock. [ 26.543047] [ 26.551327] [ 26.551327] the existing dependency chain (in reverse order) is: [ 26.558908] [ 26.558908] -> #2 (ashmem_mutex){+.+.}: [ 26.564338] __mutex_lock+0x16f/0x1a80 [ 26.568708] mutex_lock_nested+0x16/0x20 [ 26.573253] ashmem_mmap+0x53/0x410 [ 26.577362] mmap_region+0xa99/0x15a0 [ 26.581648] do_mmap+0x73c/0xf70 [ 26.585500] vm_mmap_pgoff+0x1de/0x280 [ 26.589870] SyS_mmap_pgoff+0x462/0x5f0 [ 26.594327] SyS_mmap+0x16/0x20 [ 26.598090] entry_SYSCALL_64_fastpath+0x23/0x9a [ 26.603325] [ 26.603325] -> #1 (&mm->mmap_sem){++++}: [ 26.609178] __might_fault+0x13a/0x1d0 [ 26.613549] _copy_to_user+0x2c/0xc0 [ 26.617748] filldir+0x1a7/0x320 [ 26.621599] dcache_readdir+0x12d/0x5e0 [ 26.626059] iterate_dir+0x1ca/0x530 [ 26.630257] SyS_getdents+0x225/0x450 [ 26.634540] entry_SYSCALL_64_fastpath+0x23/0x9a [ 26.639774] [ 26.639774] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 26.646499] lock_acquire+0x1d5/0x580 [ 26.650784] down_write+0x87/0x120 [ 26.654811] shmem_file_llseek+0xef/0x240 [ 26.659445] vfs_llseek+0xa2/0xd0 [ 26.663382] ashmem_llseek+0xe7/0x1f0 [ 26.667670] SyS_lseek+0xeb/0x170 [ 26.671604] entry_SYSCALL_64_fastpath+0x23/0x9a [ 26.676842] [ 26.676842] other info that might help us debug this: [ 26.676842] [ 26.684946] Chain exists of: [ 26.684946] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 26.684946] [ 26.696444] Possible unsafe locking scenario: [ 26.696444] [ 26.702461] CPU0 CPU1 [ 26.707088] ---- ---- [ 26.711718] lock(ashmem_mutex); [ 26.715135] lock(&mm->mmap_sem); [ 26.721158] lock(ashmem_mutex); [ 26.727204] lock(&sb->s_type->i_mutex_key#11); [ 26.731927] [ 26.731927] *** DEADLOCK *** [ 26.731927] [ 26.739164] 1 lock held by syzkaller975765/3471: [ 26.745567] #0: (ashmem_mutex){+.+.}, at: [<000000009fc576fd>] ashmem_llseek+0x56/0x1f0 [ 26.753858] [ 26.753858] stack backtrace: [ 26.758319] CPU: 0 PID: 3471 Comm: syzkaller975765 Not tainted 4.15.0-rc7-next-20180109+ #92 [ 26.766855] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.776171] Call Trace: [ 26.778725] dump_stack+0x194/0x257 [ 26.782316] ? arch_local_irq_restore+0x53/0x53 [ 26.786954] print_circular_bug.isra.37+0x2cd/0x2dc [ 26.791931] ? save_trace+0xe0/0x2b0 [ 26.795610] __lock_acquire+0x30a8/0x3e00 [ 26.799720] ? lock_downgrade+0x980/0x980 [ 26.803833] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 26.808815] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.813972] ? ashmem_llseek+0x56/0x1f0 [ 26.817911] ? lock_release+0xa40/0xa40 [ 26.821851] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.827872] ? vma_set_page_prot+0x16b/0x230 [ 26.832245] ? rcu_note_context_switch+0x710/0x710 [ 26.837138] ? vma_wants_writenotify+0x3b0/0x3b0 [ 26.841856] ? __might_sleep+0x95/0x190 [ 26.845794] ? ashmem_llseek+0x56/0x1f0 [ 26.849732] ? __mutex_lock+0x16f/0x1a80 [ 26.853755] ? ashmem_llseek+0x56/0x1f0 [ 26.857695] ? ashmem_llseek+0x56/0x1f0 [ 26.861633] ? mutex_lock_io_nested+0x1900/0x1900 [ 26.866443] ? vm_mmap_pgoff+0x1ed/0x280 [ 26.870475] ? selinux_mmap_addr+0x1f/0xf0 [ 26.874674] ? userfaultfd_unmap_complete+0x327/0x510 [ 26.879827] ? get_unmapped_area+0x265/0x300 [ 26.884202] lock_acquire+0x1d5/0x580 [ 26.887968] ? lock_acquire+0x1d5/0x580 [ 26.891906] ? shmem_file_llseek+0xef/0x240 [ 26.896190] ? lock_release+0xa40/0xa40 [ 26.900128] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.905979] ? rcu_note_context_switch+0x710/0x710 [ 26.910874] ? __fget_light+0x297/0x380 [ 26.914813] ? __might_sleep+0x95/0x190 [ 26.918752] down_write+0x87/0x120 [ 26.922256] ? shmem_file_llseek+0xef/0x240 [ 26.926545] ? down_read+0x150/0x150 [ 26.930224] ? selinux_capable+0x40/0x40 [ 26.934253] shmem_file_llseek+0xef/0x240 [ 26.938364] ? shmem_free_swap+0x80/0x80 [ 26.942392] vfs_llseek+0xa2/0xd0 [ 26.945810] ashmem_llseek+0xe7/0x1f0 [ 26.949575] ? ashmem_read_iter+0x230/0x230 [ 26.953862] SyS_lseek+0xeb/0x170 [ 26.957282] entry_SYSCALL_64_fastpath+0x23/0x9a [ 26.962001] RIP: 0033:0x444aa9 [ 26.9651