[....] Starting enhanced syslogd: rsyslogd[ 12.076704] audit: type=1400 audit(1516248453.131:5): avc: denied { syslog } for pid=3507 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: [ 17.216143] audit: type=1400 audit(1516248458.270:6): avc: denied { map } for pid=3647 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 '10.128.0.11' (ECDSA) to the list of known hosts. executing program [ 25.129178] audit: type=1400 audit(1516248466.183:7): avc: denied { map } for pid=3662 comm="syzkaller515543" path="/root/syzkaller515543758" 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 [ 25.132614] [ 25.155111] audit: type=1400 audit(1516248466.184:8): avc: denied { map } for pid=3662 comm="syzkaller515543" path="/dev/ashmem" dev="devtmpfs" ino=1073 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1 [ 25.156669] ====================================================== [ 25.156671] WARNING: possible circular locking dependency detected [ 25.156676] 4.15.0-rc8-next-20180117+ #99 Not tainted [ 25.156678] ------------------------------------------------------ [ 25.156680] syzkaller515543/3662 is trying to acquire lock: [ 25.156682] (&sb->s_type->i_mutex_key#11){++++}, at: [<0000000098acb0ed>] shmem_file_llseek+0xef/0x240 [ 25.222018] [ 25.222018] but task is already holding lock: [ 25.227970] (ashmem_mutex){+.+.}, at: [<00000000c8d1d248>] ashmem_llseek+0x56/0x1f0 [ 25.235831] [ 25.235831] which lock already depends on the new lock. [ 25.235831] [ 25.244114] [ 25.244114] the existing dependency chain (in reverse order) is: [ 25.251701] [ 25.251701] -> #2 (ashmem_mutex){+.+.}: [ 25.257131] __mutex_lock+0x16f/0x1a80 [ 25.261508] mutex_lock_nested+0x16/0x20 [ 25.266057] ashmem_mmap+0x53/0x410 [ 25.270194] mmap_region+0xa99/0x15a0 [ 25.274482] do_mmap+0x73c/0xf70 [ 25.278335] vm_mmap_pgoff+0x1de/0x280 [ 25.282713] SyS_mmap_pgoff+0x462/0x5f0 [ 25.287180] SyS_mmap+0x16/0x20 [ 25.290949] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.296196] [ 25.296196] -> #1 (&mm->mmap_sem){++++}: [ 25.301711] __might_fault+0x13a/0x1d0 [ 25.306092] _copy_to_user+0x2c/0xc0 [ 25.310297] filldir+0x1a7/0x320 [ 25.314161] dcache_readdir+0x12d/0x5e0 [ 25.318629] iterate_dir+0x1ca/0x530 [ 25.322838] SyS_getdents+0x225/0x450 [ 25.327136] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.332379] [ 25.332379] -> #0 (&sb->s_type->i_mutex_key#11){++++}: [ 25.339112] lock_acquire+0x1d5/0x580 [ 25.343401] down_write+0x87/0x120 [ 25.347443] shmem_file_llseek+0xef/0x240 [ 25.352082] vfs_llseek+0xa2/0xd0 [ 25.356038] ashmem_llseek+0xe7/0x1f0 [ 25.360334] SyS_lseek+0xeb/0x170 [ 25.364282] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.369527] [ 25.369527] other info that might help us debug this: [ 25.369527] [ 25.377641] Chain exists of: [ 25.377641] &sb->s_type->i_mutex_key#11 --> &mm->mmap_sem --> ashmem_mutex [ 25.377641] [ 25.389147] Possible unsafe locking scenario: [ 25.389147] [ 25.395174] CPU0 CPU1 [ 25.399809] ---- ---- [ 25.404441] lock(ashmem_mutex); [ 25.407861] lock(&mm->mmap_sem); [ 25.415630] lock(ashmem_mutex); [ 25.422440] lock(&sb->s_type->i_mutex_key#11); [ 25.427170] [ 25.427170] *** DEADLOCK *** [ 25.427170] [ 25.433195] 1 lock held by syzkaller515543/3662: [ 25.438090] #0: (ashmem_mutex){+.+.}, at: [<00000000c8d1d248>] ashmem_llseek+0x56/0x1f0 [ 25.446388] [ 25.446388] stack backtrace: [ 25.450855] CPU: 1 PID: 3662 Comm: syzkaller515543 Not tainted 4.15.0-rc8-next-20180117+ #99 [ 25.459395] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 25.468718] Call Trace: [ 25.471280] dump_stack+0x194/0x257 [ 25.474887] ? arch_local_irq_restore+0x53/0x53 [ 25.479528] print_circular_bug.isra.37+0x2cd/0x2dc [ 25.485382] ? save_trace+0xe0/0x2b0 [ 25.489065] __lock_acquire+0x30a8/0x3e00 [ 25.493182] ? lock_downgrade+0x980/0x980 [ 25.497297] ? __mutex_unlock_slowpath+0xe9/0xac0 [ 25.502110] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 25.507269] ? ashmem_llseek+0x56/0x1f0 [ 25.511212] ? lock_release+0xa40/0xa40 [ 25.515157] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.521014] ? vma_set_page_prot+0x16b/0x230 [ 25.525399] ? rcu_note_context_switch+0x710/0x710 [ 25.530295] ? vma_wants_writenotify+0x3b0/0x3b0 [ 25.535023] ? __might_sleep+0x95/0x190 [ 25.538968] ? ashmem_llseek+0x56/0x1f0 [ 25.542917] ? __mutex_lock+0x16f/0x1a80 [ 25.546944] ? ashmem_llseek+0x56/0x1f0 [ 25.550888] ? ashmem_llseek+0x56/0x1f0 [ 25.554831] ? mutex_lock_io_nested+0x1900/0x1900 [ 25.559644] ? vm_mmap_pgoff+0x1ed/0x280 [ 25.563675] ? selinux_mmap_addr+0x1f/0xf0 [ 25.567879] ? userfaultfd_unmap_complete+0x327/0x510 [ 25.573044] ? get_unmapped_area+0x265/0x300 [ 25.577426] lock_acquire+0x1d5/0x580 [ 25.581196] ? lock_acquire+0x1d5/0x580 [ 25.585494] ? shmem_file_llseek+0xef/0x240 [ 25.589783] ? lock_release+0xa40/0xa40 [ 25.593726] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 25.599579] ? rcu_note_context_switch+0x710/0x710 [ 25.604475] ? __fget_light+0x297/0x380 [ 25.608418] ? __might_sleep+0x95/0x190 [ 25.612362] down_write+0x87/0x120 [ 25.615873] ? shmem_file_llseek+0xef/0x240 [ 25.620164] ? down_read+0x150/0x150 [ 25.624108] ? selinux_capable+0x40/0x40 [ 25.628140] shmem_file_llseek+0xef/0x240 [ 25.632256] ? shmem_free_swap+0x80/0x80 [ 25.636285] vfs_llseek+0xa2/0xd0 [ 25.639709] ashmem_llseek+0xe7/0x1f0 [ 25.643477] ? ashmem_read_iter+0x230/0x230 [ 25.647775] SyS_lseek+0xeb/0x170 [ 25.651200] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 25.655923] RIP: 0033:0x43fd19 [ 25.659080] RSP: 002b:00007ffe4e7faa78 EFLAGS: 00000217 ORIG_RAX: 0000000000000008 [ 25.666756] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd19 [ 25.673998] RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000003 [ 2