[....] Starting enhanced syslogd: rsyslogd[ 17.353603] audit: type=1400 audit(1519638753.636:5): avc: denied { syslog } for pid=4089 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[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Starting mcstransd:
[....] Starting file context maintaining daemon: restorecond[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
syzkaller login: [ 23.429793] audit: type=1400 audit(1519638759.712:6): avc: denied { map } for pid=4229 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 '10.128.0.58' (ECDSA) to the list of known hosts.
executing program
[ 29.747804] audit: type=1400 audit(1519638766.030:7): avc: denied { map } for pid=4243 comm="syzkaller923784" path="/root/syzkaller923784171" 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
[ 29.750248]
[ 29.773690] audit: type=1400 audit(1519638766.030:8): avc: denied { map } for pid=4243 comm="syzkaller923784" path="/dev/ashmem" dev="devtmpfs" ino=9417 scontext=unconfined_u:system_r:insmod_t:s0-s0:c0.c1023 tcontext=system_u:object_r:device_t:s0 tclass=chr_file permissive=1
[ 29.775275] ======================================================
[ 29.775276] WARNING: possible circular locking dependency detected
[ 29.775280] 4.16.0-rc2+ #329 Not tainted
[ 29.775281] ------------------------------------------------------
[ 29.775283] syzkaller923784/4243 is trying to acquire lock:
[ 29.775284] (&mm->mmap_sem){++++}, at: [<0000000074c86253>] __might_fault+0xe0/0x1d0
[ 29.775302]
[ 29.775302] but task is already holding lock:
[ 29.842391] (ashmem_mutex){+.+.}, at: [<0000000024db7f7c>] ashmem_ioctl+0x3db/0x11b0
[ 29.850331]
[ 29.850331] which lock already depends on the new lock.
[ 29.850331]
[ 29.858610]
[ 29.858610] the existing dependency chain (in reverse order) is:
[ 29.866195]
[ 29.866195] -> #1 (ashmem_mutex){+.+.}:
[ 29.871618] __mutex_lock+0x16f/0x1a80
[ 29.876003] mutex_lock_nested+0x16/0x20
[ 29.880550] ashmem_mmap+0x53/0x410
[ 29.884663] mmap_region+0xa99/0x15a0
[ 29.888950] do_mmap+0x6c0/0xe00
[ 29.892805] vm_mmap_pgoff+0x1de/0x280
[ 29.897183] SyS_mmap_pgoff+0x462/0x5f0
[ 29.901647] SyS_mmap+0x16/0x20
[ 29.905416] do_syscall_64+0x280/0x940
[ 29.909789] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 29.915461]
[ 29.915461] -> #0 (&mm->mmap_sem){++++}:
[ 29.920974] lock_acquire+0x1d5/0x580
[ 29.925263] __might_fault+0x13a/0x1d0
[ 29.929638] _copy_from_user+0x2c/0x110
[ 29.934101] ashmem_ioctl+0x438/0x11b0
[ 29.938474] do_vfs_ioctl+0x1b1/0x1520
[ 29.942864] SyS_ioctl+0x8f/0xc0
[ 29.946720] do_syscall_64+0x280/0x940
[ 29.951094] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 29.956765]
[ 29.956765] other info that might help us debug this:
[ 29.956765]
[ 29.964871] Possible unsafe locking scenario:
[ 29.964871]
[ 29.970893] CPU0 CPU1
[ 29.975526] ---- ----
[ 29.980157] lock(ashmem_mutex);
[ 29.983576] lock(&mm->mmap_sem);
[ 29.989598] lock(ashmem_mutex);
[ 29.995535] lock(&mm->mmap_sem);
[ 29.999051]
[ 29.999051] *** DEADLOCK ***
[ 29.999051]
[ 30.005079] 1 lock held by syzkaller923784/4243:
[ 30.009799] #0: (ashmem_mutex){+.+.}, at: [<0000000024db7f7c>] ashmem_ioctl+0x3db/0x11b0
[ 30.018176]
[ 30.018176] stack backtrace:
[ 30.022640] CPU: 1 PID: 4243 Comm: syzkaller923784 Not tainted 4.16.0-rc2+ #329
[ 30.030052] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 30.039371] Call Trace:
[ 30.041927] dump_stack+0x194/0x24d
[ 30.045522] ? arch_local_irq_restore+0x53/0x53
[ 30.050160] print_circular_bug.isra.38+0x2cd/0x2dc
[ 30.055142] ? save_trace+0xe0/0x2b0
[ 30.058822] __lock_acquire+0x30a8/0x3e00
[ 30.062936] ? ashmem_ioctl+0x3db/0x11b0
[ 30.066966] ? debug_check_no_locks_freed+0x3c0/0x3c0
[ 30.072132] ? __might_sleep+0x95/0x190
[ 30.076074] ? ashmem_ioctl+0x3db/0x11b0
[ 30.080102] ? __mutex_lock+0x16f/0x1a80
[ 30.084130] ? ashmem_ioctl+0x3db/0x11b0
[ 30.088160] ? proc_nr_files+0x60/0x60
[ 30.092015] ? ashmem_ioctl+0x3db/0x11b0
[ 30.096042] ? find_held_lock+0x35/0x1d0
[ 30.100071] ? mutex_lock_io_nested+0x1900/0x1900
[ 30.104880] ? lock_downgrade+0x980/0x980
[ 30.108995] ? __mutex_unlock_slowpath+0xe9/0xac0
[ 30.113807] ? find_held_lock+0x35/0x1d0
[ 30.117834] ? lock_downgrade+0x980/0x980
[ 30.121949] ? vma_set_page_prot+0x16b/0x230
[ 30.126324] lock_acquire+0x1d5/0x580
[ 30.130094] ? lock_acquire+0x1d5/0x580
[ 30.134034] ? __might_fault+0xe0/0x1d0
[ 30.137976] ? lock_release+0xa40/0xa40
[ 30.141921] ? trace_event_raw_event_sched_switch+0x810/0x810
[ 30.147774] ? __might_sleep+0x95/0x190
[ 30.151713] __might_fault+0x13a/0x1d0
[ 30.155566] ? __might_fault+0xe0/0x1d0
[ 30.159508] _copy_from_user+0x2c/0x110
[ 30.163447] ashmem_ioctl+0x438/0x11b0
[ 30.167302] ? ashmem_release+0x190/0x190
[ 30.171419] ? trace_event_raw_event_sched_switch+0x810/0x810
[ 30.177272] ? down_read_killable+0x180/0x180
[ 30.181734] ? rcu_note_context_switch+0x710/0x710
[ 30.186629] ? ashmem_release+0x190/0x190
[ 30.190742] do_vfs_ioctl+0x1b1/0x1520
[ 30.194597] ? ioctl_preallocate+0x2b0/0x2b0
[ 30.198975] ? selinux_capable+0x40/0x40
[ 30.203004] ? putname+0xf3/0x130
[ 30.206422] ? fput+0xd2/0x140
[ 30.209583] ? SyS_mmap_pgoff+0x243/0x5f0
[ 30.213700] ? security_file_ioctl+0x7d/0xb0
[ 30.218072] ? security_file_ioctl+0x89/0xb0
[ 30.222448] SyS_ioctl+0x8f/0xc0
[ 30.225781] ? do_vfs_ioctl+0x1520/0x1520
[ 30.229896] do_syscall_64+0x280/0x940
[ 30.233749] ? __do_page_fault+0xc90/0xc90
[ 30.237948] ? trace_hardirqs_on_thunk+0x1a/0x1c
[ 30.242671] ? syscall_return_slowpath+0x550/0x550
[ 30.247567] ? syscall_return_slowpath+0x2ac/0x550
[ 30.252464] ? prepare_exit_to_usermode+0x350/0x350
[ 30.257449] ? entry_SYSCALL_64_after_hwframe+0x52/0xb7
[ 30.262779] ? trace_hardirqs_off_thunk+0x1a/0x1c
[ 30.267590] entry_SYSCALL_64_after_hwframe+0x42/0xb7
[ 30.272743] RIP: 0033:0x43fd19
[ 30.275903] RSP: 002b:00007ffe04d2fda8 EFLAGS: 00000217 ORIG_RAX: 0000000000000010
[ 30.283575] RAX: ffffffffffffffda RBX: 00000000004002c8 RCX: 000000000043fd19
[ 30.290809] RDX: 0000000000000000 RSI: 0000000000007709 RDI: 0000000000000003
[ 30.298046] RBP: 000000