[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting periodic command scheduler: cron[?25l[?1c7[ ok 8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. [ 26.469156] kauditd_printk_skb: 7 callbacks suppressed [ 26.469168] audit: type=1800 audit(1540182909.041:29): pid=5202 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 26.494979] audit: type=1800 audit(1540182909.051:30): pid=5202 uid=0 auid=4294967295 ses=4294967295 subj=_ op=collect_data cause=failed(directio) comm="startpar" name="rmnologin" dev="sda1" ino=2423 res=0 Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.105' (ECDSA) to the list of known hosts. 2018/10/22 04:36:00 parsed 1 programs 2018/10/22 04:36:01 executed programs: 0 syzkaller login: [ 78.916619] IPVS: ftp: loaded support on port[0] = 21 [ 79.159276] bridge0: port 1(bridge_slave_0) entered blocking state [ 79.166416] bridge0: port 1(bridge_slave_0) entered disabled state [ 79.173590] device bridge_slave_0 entered promiscuous mode [ 79.191969] bridge0: port 2(bridge_slave_1) entered blocking state [ 79.198520] bridge0: port 2(bridge_slave_1) entered disabled state [ 79.205696] device bridge_slave_1 entered promiscuous mode [ 79.223405] IPv6: ADDRCONF(NETDEV_UP): veth0_to_bridge: link is not ready [ 79.242430] IPv6: ADDRCONF(NETDEV_UP): veth1_to_bridge: link is not ready [ 79.291839] bond0: Enslaving bond_slave_0 as an active interface with an up link [ 79.311939] bond0: Enslaving bond_slave_1 as an active interface with an up link [ 79.387361] IPv6: ADDRCONF(NETDEV_UP): team_slave_0: link is not ready [ 79.394762] team0: Port device team_slave_0 added [ 79.411124] IPv6: ADDRCONF(NETDEV_UP): team_slave_1: link is not ready [ 79.418490] team0: Port device team_slave_1 added [ 79.435236] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_0: link becomes ready [ 79.456920] IPv6: ADDRCONF(NETDEV_CHANGE): team_slave_1: link becomes ready [ 79.475131] IPv6: ADDRCONF(NETDEV_CHANGE): veth0_to_bridge: link becomes ready [ 79.496537] IPv6: ADDRCONF(NETDEV_CHANGE): veth1_to_bridge: link becomes ready [ 79.641477] bridge0: port 2(bridge_slave_1) entered blocking state [ 79.647988] bridge0: port 2(bridge_slave_1) entered forwarding state [ 79.654793] bridge0: port 1(bridge_slave_0) entered blocking state [ 79.661141] bridge0: port 1(bridge_slave_0) entered forwarding state [ 80.171964] 8021q: adding VLAN 0 to HW filter on device bond0 [ 80.224294] IPv6: ADDRCONF(NETDEV_UP): veth0: link is not ready [ 80.274441] IPv6: ADDRCONF(NETDEV_UP): veth1: link is not ready [ 80.280572] IPv6: ADDRCONF(NETDEV_CHANGE): veth1: link becomes ready [ 80.287897] IPv6: ADDRCONF(NETDEV_CHANGE): veth0: link becomes ready [ 80.340341] 8021q: adding VLAN 0 to HW filter on device team0 [ 80.968570] [ 80.970223] ===================================== [ 80.975038] WARNING: bad unlock balance detected! [ 80.979857] 4.19.0-rc8+ #73 Not tainted [ 80.983929] ------------------------------------- [ 80.988751] syz-executor0/5729 is trying to release lock (&file->mut) at: [ 80.995668] [] ucma_destroy_id+0x2cb/0x550 [ 81.001443] but there are no more locks to release! [ 81.006436] [ 81.006436] other info that might help us debug this: [ 81.013117] 1 lock held by syz-executor0/5729: [ 81.017685] #0: 00000000d467406b (&file->mut){+.+.}, at: ucma_destroy_id+0x26b/0x550 [ 81.025655] [ 81.025655] stack backtrace: [ 81.030141] CPU: 1 PID: 5729 Comm: syz-executor0 Not tainted 4.19.0-rc8+ #73 [ 81.037305] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 81.046681] Call Trace: [ 81.049260] dump_stack+0x1c4/0x2b6 [ 81.052875] ? dump_stack_print_info.cold.1+0x20/0x20 [ 81.058051] ? vprintk_func+0x85/0x181 [ 81.061937] ? ucma_destroy_id+0x2cb/0x550 [ 81.066161] print_unlock_imbalance_bug.cold.48+0xcc/0xd8 [ 81.071682] lock_release+0x785/0x970 [ 81.075469] ? ucma_destroy_id+0x2cb/0x550 [ 81.079687] ? lock_downgrade+0x900/0x900 [ 81.083822] ? radix_tree_descend+0x2e0/0x2e0 [ 81.088309] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 81.093837] ? node_tag_set+0xc6/0x170 [ 81.097722] __mutex_unlock_slowpath+0x102/0x8c0 [ 81.102543] ? wait_for_completion+0x8a0/0x8a0 [ 81.107121] ? radix_tree_delete_item+0x188/0x350 [ 81.111950] ? radix_tree_lookup+0x30/0x30 [ 81.116174] mutex_unlock+0xd/0x10 [ 81.119703] ucma_destroy_id+0x2cb/0x550 [ 81.123894] ? ucma_close+0x310/0x310 [ 81.127695] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 81.133217] ? _copy_from_user+0xdf/0x150 [ 81.137360] ? ucma_close+0x310/0x310 [ 81.141156] ucma_write+0x365/0x460 [ 81.144767] ? ucma_open+0x3f0/0x3f0 [ 81.148464] ? find_held_lock+0x36/0x1c0 [ 81.152514] __vfs_write+0x119/0x9f0 [ 81.156215] ? __fget_light+0x2e9/0x430 [ 81.160176] ? ucma_open+0x3f0/0x3f0 [ 81.163883] ? kernel_read+0x120/0x120 [ 81.167757] ? lock_release+0x970/0x970 [ 81.171776] ? arch_local_save_flags+0x40/0x40 [ 81.176354] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 81.181791] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 81.187438] ? security_file_permission+0x1c2/0x230 [ 81.192445] ? rw_verify_area+0x118/0x360 [ 81.196581] vfs_write+0x1fc/0x560 [ 81.200108] ksys_write+0x101/0x260 [ 81.203829] ? __ia32_sys_read+0xb0/0xb0 [ 81.207883] ? __bpf_trace_preemptirq_template+0x30/0x30 [ 81.213324] __x64_sys_write+0x73/0xb0 [ 81.217201] do_syscall_64+0x1b9/0x820 [ 81.221083] ? entry_SYSCALL_64_after_hwframe+0x3e/0xbe [ 81.226432] ? syscall_return_slowpath+0x5e0/0x5e0 [ 81.231447] ? trace_hardirqs_on_caller+0x310/0x310 [ 81.236453] ? prepare_exit_to_usermode+0x3b0/0x3b0 [ 81.241456] ? recalc_sigpending_tsk+0x180/0x180 [ 81.246303] ? kasan_check_write+0x14/0x20 [ 81.250531] ? trace_hardirqs_off_thunk+0x1a/0x1c [ 81.255365] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 81.260537] RIP: 0033:0x457569 [ 81.263716] Code: fd b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 cb b3 fb ff c3 66 2e 0f 1f 84 00 00 00 00 [ 81.282670] RSP: 002b:00007f823e86dc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 [ 81.290367] RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000457569 [ 81.297617] RDX: 0000000000000018 RSI: 0000000020000280 RDI: 0000000000000005 [ 81.304880] RBP: 000000000072bfa0 R08: 0000000000000000 R09: 0000000000000000 [ 81.312136] R10: 0000000000000000 R11: 0000000000000246 R12: 00007f823e86e6d4 [ 81.319387] R13: 00000000004cb4f8 R14: 00000000004d8b68 R15: 00000000ffffffff