[....] Starting enhanced syslogd: rsyslogd[ 12.759985] audit: type=1400 audit(1516401613.189:5): avc: denied { syslog } for pid=3504 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 OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting file context maintaining daemon: restorecond[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 syzkaller login: [ 19.575041] audit: type=1400 audit(1516401620.004:6): avc: denied { map } for pid=3644 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 '10.128.15.238' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 25.819354] audit: type=1400 audit(1516401626.249:7): avc: denied { map } for pid=3658 comm="syzkaller382504" path="/root/syzkaller382504175" 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 RTNETLINK answers: Operation not supported RTNETLINK answers: No buffer space available RTNETLINK answers: Operation not supported [ 26.170139] ip (3721) used greatest stack depth: 16224 bytes left [ 26.207636] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument executing program [ 26.554386] [ 26.556033] ============================================ [ 26.561456] WARNING: possible recursive locking detected [ 26.566874] 4.15.0-rc8+ #269 Not tainted [ 26.570900] -------------------------------------------- [ 26.576317] syzkaller382504/3658 is trying to acquire lock: [ 26.581995] (&vq->mutex){+.+.}, at: [<00000000857a331f>] vhost_chr_write_iter+0x278/0x1580 [ 26.590484] [ 26.590484] but task is already holding lock: [ 26.596422] (&vq->mutex){+.+.}, at: [<00000000857a331f>] vhost_chr_write_iter+0x278/0x1580 [ 26.604888] [ 26.604888] other info that might help us debug this: [ 26.611527] Possible unsafe locking scenario: [ 26.611527] [ 26.617554] CPU0 [ 26.620109] ---- [ 26.622659] lock(&vq->mutex); [ 26.625904] lock(&vq->mutex); [ 26.629152] [ 26.629152] *** DEADLOCK *** [ 26.629152] [ 26.635178] May be due to missing lock nesting notation [ 26.635178] [ 26.642073] 1 lock held by syzkaller382504/3658: [ 26.646826] #0: (&vq->mutex){+.+.}, at: [<00000000857a331f>] vhost_chr_write_iter+0x278/0x1580 [ 26.655726] [ 26.655726] stack backtrace: [ 26.660194] CPU: 0 PID: 3658 Comm: syzkaller382504 Not tainted 4.15.0-rc8+ #269 [ 26.667608] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 26.676937] Call Trace: [ 26.679499] dump_stack+0x194/0x257 [ 26.683101] ? arch_local_irq_restore+0x53/0x53 [ 26.687743] __lock_acquire+0xe8f/0x3e00 [ 26.691797] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.696959] ? get_kernel_page+0x110/0x110 [ 26.701168] ? __lru_cache_add+0x2a4/0x410 [ 26.705378] ? print_irqtrace_events+0x270/0x270 [ 26.710111] ? __handle_mm_fault+0x1a0c/0x3ce0 [ 26.714665] ? check_noncircular+0x20/0x20 [ 26.718880] ? get_mem_cgroup_from_mm+0x710/0x710 [ 26.723699] ? lru_cache_add_file+0x20/0x20 [ 26.728002] ? check_noncircular+0x20/0x20 [ 26.732215] ? check_noncircular+0x20/0x20 [ 26.736421] ? __lock_acquire+0x664/0x3e00 [ 26.740629] ? mark_held_locks+0xaf/0x100 [ 26.744751] lock_acquire+0x1d5/0x580 [ 26.748530] ? lock_acquire+0x1d5/0x580 [ 26.752484] ? vhost_chr_write_iter+0x278/0x1580 [ 26.757212] ? lock_release+0xa40/0xa40 [ 26.761155] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.767012] ? do_raw_spin_trylock+0x190/0x190 [ 26.771575] ? rcu_note_context_switch+0x710/0x710 [ 26.776484] ? __might_sleep+0x95/0x190 [ 26.780430] ? vhost_chr_write_iter+0x278/0x1580 [ 26.785158] __mutex_lock+0x16f/0x1a80 [ 26.789020] ? vhost_chr_write_iter+0x278/0x1580 [ 26.793749] ? vhost_chr_write_iter+0x278/0x1580 [ 26.798475] ? __thp_get_unmapped_area+0x130/0x130 [ 26.803387] ? __lock_acquire+0x664/0x3e00 [ 26.807592] ? mutex_lock_io_nested+0x1900/0x1900 [ 26.812408] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 26.817568] ? find_held_lock+0x35/0x1d0 [ 26.821600] ? __might_fault+0x110/0x1d0 [ 26.825634] ? lock_downgrade+0x980/0x980 [ 26.829752] ? lock_release+0xa40/0xa40 [ 26.833696] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 26.839551] ? __might_sleep+0x95/0x190 [ 26.843497] ? kasan_check_write+0x14/0x20 [ 26.847703] ? copyin+0x91/0xb0 [ 26.850952] ? _copy_from_iter+0x367/0xf30 [ 26.855159] ? __handle_mm_fault+0x80e/0x3ce0 [ 26.859625] ? check_noncircular+0x20/0x20 [ 26.863837] ? copy_page_to_iter+0xe10/0xe10 [ 26.868237] mutex_lock_nested+0x16/0x20 [ 26.872269] ? mutex_lock_nested+0x16/0x20 [ 26.876477] vhost_chr_write_iter+0x278/0x1580 [ 26.881035] ? handle_mm_fault+0x248/0x8d0 [ 26.885253] ? find_held_lock+0x3/0x1d0 [ 26.889198] ? vhost_new_umem_range+0x740/0x740 [ 26.893847] ? __do_page_fault+0x5f7/0xc90 [ 26.898056] vhost_net_chr_write_iter+0x59/0x70 [ 26.902696] __vfs_write+0x684/0x970 [ 26.906382] ? kernel_read+0x120/0x120 [ 26.910241] ? _cond_resched+0x14/0x30 [ 26.914103] ? avc_policy_seqno+0x9/0x20 [ 26.918136] ? selinux_file_permission+0x82/0x460 [ 26.922958] ? rw_verify_area+0xe5/0x2b0 [ 26.926988] ? __fdget_raw+0x20/0x20 [ 26.930681] vfs_write+0x189/0x510 [ 26.934193] SyS_write+0xef/0x220 [ 26.937617] ? filp_open+0x70/0x70 [ 26.941126] ? SyS_read+0x220/0x220 [ 26.944733] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 26.949718] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 26.954446] entr