[....] Starting enhanced syslogd: rsyslogd[ 13.411501] audit: type=1400 audit(1516403539.075:5): avc: denied { syslog } for pid=3502 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: [ 19.858362] audit: type=1400 audit(1516403545.522:6): avc: denied { map } for pid=3642 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 '10.128.0.21' (ECDSA) to the list of known hosts. net.ipv6.conf.syz0.accept_dad = 0 net.ipv6.conf.syz0.router_solicitations = 0 [ 26.165525] audit: type=1400 audit(1516403551.829:7): avc: denied { map } for pid=3656 comm="syzkaller392619" path="/root/syzkaller392619563" 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 [ 26.558333] 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 [ 26.906920] [ 26.908564] ============================================ [ 26.913988] WARNING: possible recursive locking detected [ 26.919411] 4.15.0-rc8+ #179 Not tainted [ 26.923440] -------------------------------------------- [ 26.928859] syzkaller392619/3656 is trying to acquire lock: [ 26.934550] (&vq->mutex){+.+.}, at: [<00000000ae35a035>] vhost_chr_write_iter+0x278/0x1580 [ 26.943025] [ 26.943025] but task is already holding lock: [ 26.948968] (&vq->mutex){+.+.}, at: [<00000000ae35a035>] vhost_chr_write_iter+0x278/0x1580 [ 26.957439] [ 26.957439] other info that might help us debug this: [ 26.964072] Possible unsafe locking scenario: [ 26.964072] [ 26.970095] CPU0 [ 26.972646] ---- [ 26.975202] lock(&vq->mutex); [ 26.978449] lock(&vq->mutex); [ 26.982304] [ 26.982304] *** DEADLOCK *** [ 26.982304] [ 26.988333] May be due to missing lock nesting notation [ 26.988333] [ 26.995229] 1 lock held by syzkaller392619/3656: [ 26.999949] #0: (&vq->mutex){+.+.}, at: [<00000000ae35a035>] vhost_chr_write_iter+0x278/0x1580 [ 27.008849] [ 27.008849] stack backtrace: [ 27.013324] CPU: 1 PID: 3656 Comm: syzkaller392619 Not tainted 4.15.0-rc8+ #179 [ 27.020737] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 27.030062] Call Trace: [ 27.032624] dump_stack+0x194/0x257 [ 27.036222] ? arch_local_irq_restore+0x53/0x53 [ 27.040870] __lock_acquire+0xe8f/0x3e00 [ 27.044908] ? debug_check_no_locks_freed+0x3c0/0x3c0 [ 27.050075] ? print_irqtrace_events+0x270/0x270 [ 27.054805] ? pagevec_lru_move_fn+0x178/0x230 [ 27.059356] ? lock_downgrade+0x980/0x980 [ 27.063480] ? lock_release+0xa40/0xa40 [ 27.067426] ? print_irqtrace_events+0x270/0x270 [ 27.072155] ? _raw_spin_unlock_irqrestore+0x31/0xba [ 27.077245] ? pagevec_lru_move_fn+0x1a4/0x230 [ 27.081808] ? get_kernel_page+0x110/0x110 [ 27.086026] ? check_noncircular+0x20/0x20 [ 27.090242] ? __lock_acquire+0x664/0x3e00 [ 27.094454] ? __pagevec_lru_add+0x30/0x30 [ 27.098658] ? save_stack+0xa3/0xd0 [ 27.102258] lock_acquire+0x1d5/0x580 [ 27.106041] ? lock_acquire+0x1d5/0x580 [ 27.109987] ? vhost_chr_write_iter+0x278/0x1580 [ 27.114715] ? lru_cache_add+0x1c7/0x3a0 [ 27.118745] ? lock_release+0xa40/0xa40 [ 27.122694] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.128547] ? __mem_cgroup_threshold+0x8f0/0x8f0 [ 27.133367] ? rcu_note_context_switch+0x710/0x710 [ 27.138266] ? __might_sleep+0x95/0x190 [ 27.142226] ? vhost_chr_write_iter+0x278/0x1580 [ 27.146963] __mutex_lock+0x16f/0x1a80 [ 27.150822] ? vhost_chr_write_iter+0x278/0x1580 [ 27.155558] ? vhost_chr_write_iter+0x278/0x1580 [ 27.160286] ? check_noncircular+0x20/0x20 [ 27.164502] ? do_huge_pmd_anonymous_page+0xab4/0x1b00 [ 27.169751] ? mutex_lock_io_nested+0x1900/0x1900 [ 27.174563] ? pudp_huge_clear_flush+0x1f0/0x1f0 [ 27.179289] ? lock_release+0xa40/0xa40 [ 27.183232] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.189090] ? do_raw_spin_trylock+0x190/0x190 [ 27.193643] ? find_held_lock+0x35/0x1d0 [ 27.197674] ? __might_fault+0x110/0x1d0 [ 27.201705] ? lock_downgrade+0x980/0x980 [ 27.205823] ? lock_release+0xa40/0xa40 [ 27.209767] ? trace_event_raw_event_sched_switch+0x800/0x800 [ 27.215623] ? __might_sleep+0x95/0x190 [ 27.219567] ? kasan_check_write+0x14/0x20 [ 27.223772] ? copyin+0x91/0xb0 [ 27.227029] ? _copy_from_iter+0x367/0xf30 [ 27.231235] ? depot_save_stack+0x3b5/0x490 [ 27.235526] ? lock_downgrade+0x980/0x980 [ 27.239643] ? lock_release+0xa40/0xa40 [ 27.243589] ? copy_page_to_iter+0xe10/0xe10 [ 27.247974] ? do_raw_spin_trylock+0x190/0x190 [ 27.252537] mutex_lock_nested+0x16/0x20 [ 27.256584] ? mutex_lock_nested+0x16/0x20 [ 27.260790] vhost_chr_write_iter+0x278/0x1580 [ 27.265349] ? _raw_spin_unlock_irqrestore+0xa6/0xba [ 27.270422] ? depot_save_stack+0x3b5/0x490 [ 27.274723] ? match_held_lock+0x3/0xa00 [ 27.278756] ? vhost_new_umem_range+0x740/0x740 [ 27.283402] ? __handle_mm_fault+0x80e/0x3ce0 [ 27.287878] ? find_held_lock+0x35/0x1d0 [ 27.291911] vhost_net_chr_write_iter+0x59/0x70 [ 27.296552] __vfs_write+0x684/0x970 [ 27.300246] ? kernel_read+0x120/0x120 [ 27.304106] ? _cond_resched+0x14/0x30 [ 27.307969] ? avc_policy_seqno+0x9/0x20 [ 27.312000] ? selinux_file_permission+0x82/0x460 [ 27.316821] ? rw_verify_area+0xe5/0x2b0 [ 27.320862] ? __fdget_raw+0x20/0x20 [ 27.324547] vfs_write+0x189/0x510 [ 27.328058] SyS_write+0xef/0x220 [ 27.331480] ? __do_page_fault+0x3d6/0xc90 [ 27.335682] ? SyS_read+0x220/0x220 [ 27.339279] ? do_fast_syscall_32+0x156/0xf9d [ 27.343744] ? SyS_read+0x220/0x220 [ 27.347359] do_fast_syscall_32+0x3ee/0xf9d [ 27.351659] ? do_int80_syscall_32+0x9d0/0x9d0 [ 27.356228] ? kasan_check_read+0x11/0x20 [ 27.360347] ? syscall_return_slowpath+0x550/0x550 [ 27.365249] ? SyS_rt_sigaction+0x94/0x1b0 [ 27.369461] ? SyS_sigprocmask+0x4b0/0x4b0 [ 27.373664] ? SyS_read+0x184/0x220 [ 27.377263] ? retint_user+0x18/0x18 [ 27.380947] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 27.385759] entry_SYSENTER_compat+0x54/0x63 [ 27.390137] RIP: 0023:0xf7ff0c79 [ 27.393470] RSP: 002b:00000000ffd6751c EFLAGS: 00000286 ORIG_RAX: 0000000000000004 [ 27.401146] RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 0000000020baff98 [ 27.4083