[....] Starting enhanced syslogd: rsyslogd[ 13.086487] audit: type=1400 audit(1516395646.754:5): avc: denied { syslog } for pid=3511 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: [ 19.657330] audit: type=1400 audit(1516395653.324:6): avc: denied { map } for pid=3650 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 '10.128.15.232' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 26.708562] audit: type=1400 audit(1516395660.376:7): avc: denied { map } for pid=3664 comm="syzkaller872135" path="/root/syzkaller872135936" 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 RTNETLINK answers: Operation not supported [ 26.976306] IPv6: ADDRCONF(NETDEV_UP): bridge0: link is not ready RTNETLINK answers: Operation not supported RTNETLINK answers: Operation not supported RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument RTNETLINK answers: Invalid argument executing program [ 27.286211] [ 27.287848] ============================================ [ 27.293263] WARNING: possible recursive locking detected [ 27.298678] 4.15.0-rc8+ #269 Not tainted [ 27.302703] -------------------------------------------- [ 27.308122] syzkaller872135/3664 is trying to acquire lock: [ 27.313796] (&vq->mutex){+.+.}, at: [<00000000c51bd4b0>] vhost_chr_write_iter+0x278/0x1580 [ 27.322264] [ 27.322264] but task is already holding lock: [ 27.328203] (&vq->mutex){+.+.}, at: [<00000000c51bd4b0>] vhost_chr_write_iter+0x278/0x1580 [ 27.336670] [ 27.336670] other info that might help us debug this: [ 27.343301] Possible unsafe locking scenario: [ 27.343301] [ 27.349323] CPU0 [ 27.351870] ---- [ 27.354417] lock(&vq->mutex); [ 27.357660] lock(&vq->mutex); [ 27.360906] [ 27.360906] *** DEADLOCK *** [ 27.360906] [ 27.366927] May be due to missing lock nesting notation [ 27.366927] [ 27.373817] 1 lock held by syzkaller872135/3664: [ 27.378534] #0: (&vq->mutex){+.+.}, at: [<00000000c51bd4b0>] vhost_chr_write_iter+0x278/0x1580 [ 27.387427] [ 27.387427] stack backtrace: [ 27.391889] CPU: 0 PID: 3664 Comm: syzkaller872135 Not tainted 4.15.0-rc8+ #269 [ 27.399300] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.408618] Call Trace: [ 27.411177] dump_stack+0x194/0x257 [ 27.414770] ? arch_local_irq_restore+0x53/0x53 [ 27.419407] __lock_acquire+0xe8f/0x3e00 [ 27.423434] ? check_noncircular+0x20/0x20 [ 27.427639] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 27.432793] ? __lock_acquire+0x664/0x3e00 [ 27.436993] ? check_noncircular+0x20/0x20 [ 27.441196] ? find_held_lock+0x35/0x1d0 [ 27.445229] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 27.450383] ? check_noncircular+0x20/0x20 [ 27.454584] ? print_irqtrace_events+0x270/0x270 [ 27.459306] ? find_held_lock+0x35/0x1d0 [ 27.463332] ? print_irqtrace_events+0x270/0x270 [ 27.468059] ? is_bpf_text_address+0x7b/0x120 [ 27.472521] ? lock_downgrade+0x980/0x980 [ 27.476638] ? check_noncircular+0x20/0x20 [ 27.480838] ? __lock_acquire+0x664/0x3e00 [ 27.485041] ? __lock_acquire+0x664/0x3e00 [ 27.489254] ? lock_downgrade+0x980/0x980 [ 27.493373] lock_acquire+0x1d5/0x580 [ 27.497142] ? lock_acquire+0x1d5/0x580 [ 27.501088] ? vhost_chr_write_iter+0x278/0x1580 [ 27.505811] ? lock_release+0xa40/0xa40 [ 27.509753] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.515603] ? __lru_cache_add+0x2a4/0x410 [ 27.519807] ? rcu_note_context_switch+0x710/0x710 [ 27.524702] ? __might_sleep+0x95/0x190 [ 27.528642] ? vhost_chr_write_iter+0x278/0x1580 [ 27.533364] __mutex_lock+0x16f/0x1a80 [ 27.537219] ? vhost_chr_write_iter+0x278/0x1580 [ 27.541941] ? vhost_chr_write_iter+0x278/0x1580 [ 27.546674] ? mutex_lock_io_nested+0x1900/0x1900 [ 27.551483] ? get_mem_cgroup_from_mm+0x710/0x710 [ 27.556294] ? lru_cache_add_file+0x20/0x20 [ 27.560581] ? __mem_cgroup_threshold+0x8f0/0x8f0 [ 27.565390] ? find_held_lock+0x35/0x1d0 [ 27.569417] ? __might_fault+0x110/0x1d0 [ 27.573443] ? lock_downgrade+0x980/0x980 [ 27.577560] ? lock_release+0xa40/0xa40 [ 27.581499] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.587351] ? lock_release+0xa40/0xa40 [ 27.591290] ? __might_sleep+0x95/0x190 [ 27.595231] ? kasan_check_write+0x14/0x20 [ 27.599431] ? copyin+0x91/0xb0 [ 27.602676] ? _copy_from_iter+0x367/0xf30 [ 27.606878] ? _raw_spin_unlock+0x22/0x30 [ 27.610991] ? __handle_mm_fault+0x80e/0x3ce0 [ 27.615452] ? check_noncircular+0x20/0x20 [ 27.619655] ? copy_page_to_iter+0xe10/0xe10 [ 27.624030] mutex_lock_nested+0x16/0x20 [ 27.628059] ? mutex_lock_nested+0x16/0x20 [ 27.632259] vhost_chr_write_iter+0x278/0x1580 [ 27.636807] ? handle_mm_fault+0x248/0x8d0 [ 27.641008] ? find_held_lock+0x3/0x1d0 [ 27.644952] ? vhost_new_umem_range+0x740/0x740 [ 27.649591] ? __do_page_fault+0x5f7/0xc90 [ 27.653794] vhost_net_chr_write_iter+0x59/0x70 [ 27.658429] __vfs_write+0x684/0x970 [ 27.662111] ? kernel_read+0x120/0x120 [ 27.665966] ? _cond_resched+0x14/0x30 [ 27.669822] ? avc_policy_seqno+0x9/0x20 [ 27.673860] ? selinux_file_permission+0x82/0x460 [ 27.678672] ? rw_verify_area+0xe5/0x2b0 [ 27.682702] ? __fdget_raw+0x20/0x20 [ 27.686752] vfs_write+0x189/0x510 [ 27.690272] SyS_write+0xef/0x220 [ 27.693690] ? filp_open+0x70/0x70 [ 27.697198] ? SyS_read+0x220/0x220 [ 27.700791] ? trace_hardirqs_on_caller+0x421/0x5c0 [ 27.705773] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 27.710497] entry_SYSCALL_64_fastpath+0x29/0xa0 [ 27.715221] RIP: 0033:0x444d89 [ 27.718377] RSP: 002b:00007ffcf2147a88 EFLAGS: 00000207 ORIG_RAX: 0000000000000001 [ 27.726050] RAX: ffffffffffffffda RBX: 00000000004a6692 RCX: 0000000000444d89 [ 27.733288] RDX: 0000000000000068 RSI: 0000000020e4200