[....] Starting enhanced syslogd: rsyslogd[ 11.056266] audit: type=1400 audit(1514929287.158:4): avc: denied { syslog } for pid=3178 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 Warning: Permanently added '10.128.0.58' (ECDSA) to the list of known hosts. executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program executing program syzkaller login: [ 21.666781] [ 21.667322] ===================================== [ 21.667967] [ BUG: bad unlock balance detected! ] [ 21.668680] 4.9.74-g9e5dd8e #12 Not tainted [ 21.669254] ------------------------------------- [ 21.669896] syzkaller010086/3702 is trying to release lock (mrt_lock) at: [ 21.670903] [] ipmr_mfc_seq_stop+0xe4/0x140 [ 21.671695] but there are no more locks to release! [ 21.672358] [ 21.672358] other info that might help us debug this: [ 21.673239] 1 lock held by syzkaller010086/3702: [ 21.673904] #0: (&p->lock){+.+.+.}, at: [] seq_read+0xdd/0x1290 [ 21.675178] [ 21.675178] stack backtrace: [ 21.675790] CPU: 1 PID: 3702 Comm: syzkaller010086 Not tainted 4.9.74-g9e5dd8e #12 [ 21.676804] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 21.678030] ffff8801c7eef878 ffffffff81d91d19 ffffffff849b0678 ffff8801c977c800 [ 21.679199] ffffffff834e5574 ffffffff849b0678 ffff8801c977d088 ffff8801c7eef8a8 [ 21.680398] ffffffff81235ad4 dffffc0000000000 ffffffff849b0678 00000000ffffffff [ 21.681545] Call Trace: [ 21.681907] [] dump_stack+0xc1/0x128 [ 21.682617] [] ? ipmr_mfc_seq_stop+0xe4/0x140 [ 21.683444] [] print_unlock_imbalance_bug+0x174/0x1a0 [ 21.684390] [] lock_release+0x6f8/0xb80 [ 21.685139] [] ? memcpy+0x45/0x50 [ 21.685827] [] ? ipmr_mfc_seq_stop+0xe4/0x140 [ 21.686666] [] _raw_read_unlock+0x1a/0x50 [ 21.690670] [] ipmr_mfc_seq_stop+0xe4/0x140 [ 21.696619] [] traverse+0x3a7/0x900 [ 21.701868] [] ? seq_buf_alloc+0x80/0x80 [ 21.707562] [] seq_read+0x7ea/0x1290 [ 21.712900] [] ? __lock_acquire+0x629/0x3640 [ 21.718929] [] ? seq_escape+0x200/0x200 [ 21.724521] [] ? seq_escape+0x200/0x200 [ 21.730114] [] proc_reg_read+0xef/0x170 [ 21.735709] [] ? proc_reg_write+0x170/0x170 [ 21.741646] [] __vfs_read+0x103/0x670 [ 21.747066] [] ? default_llseek+0x290/0x290 [ 21.753006] [] ? fsnotify+0x86/0xf30 [ 21.758338] [] ? fsnotify+0xf30/0xf30 [ 21.763756] [] ? avc_policy_seqno+0x9/0x20 [ 21.769611] [] ? selinux_file_permission+0x82/0x460 [ 21.776253] [] ? security_file_permission+0x89/0x1e0 [ 21.782973] [] ? rw_verify_area+0xe5/0x2b0 [ 21.788841] [] vfs_read+0x11e/0x380 [ 21.794083] [] SyS_pread64+0x13f/0x170 [ 21.799589] [] ? SyS_write+0x1b0/0x1b0 [ 21.805095] [] ? _raw_spin_unlock_irq+0x27/0x50 [ 21.811384] [] sys32_pread+0x39/0x50 executing program [ 21.816712] [] ? sys32_waitpid+0x30/0x30 [ 21.822390] [] do_fast_syscall_32+0x2f7/0x890 [ 21.828499] [] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 21.835143] [] entry_SYSENTER_compat+0x51/0x60