[ 91.812825][ T27] audit: type=1800 audit(1579854357.270:26): pid=9510 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [....] Starting periodic command scheduler: cron[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c. [ 92.813375][ T27] kauditd_printk_skb: 2 callbacks suppressed [ 92.813387][ T27] audit: type=1800 audit(1579854358.280:29): pid=9510 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rc.local" dev="sda1" ino=2432 res=0 [ 92.840003][ T27] audit: type=1800 audit(1579854358.280:30): pid=9510 uid=0 auid=4294967295 ses=4294967295 subj==unconfined 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 '10.128.0.179' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 440.247182][ C1] rcu: INFO: rcu_preempt self-detected stall on CPU [ 440.253952][ C1] rcu: 1-....: (1 GPs behind) idle=932/1/0x4000000000000002 softirq=17178/17179 fqs=5250 [ 440.264067][ C1] (t=10502 jiffies g=9617 q=36) [ 440.268996][ C1] NMI backtrace for cpu 1 [ 440.273322][ C1] CPU: 1 PID: 9663 Comm: syz-executor787 Not tainted 5.5.0-rc6-syzkaller #0 [ 440.282085][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 440.292143][ C1] Call Trace: [ 440.295485][ C1] <IRQ> [ 440.298440][ C1] dump_stack+0x197/0x210 [ 440.302807][ C1] nmi_cpu_backtrace.cold+0x70/0xb2 [ 440.308062][ C1] ? lapic_can_unplug_cpu.cold+0x3a/0x3a [ 440.313680][ C1] nmi_trigger_cpumask_backtrace+0x23b/0x28b [ 440.319752][ C1] arch_trigger_cpumask_backtrace+0x14/0x20 [ 440.325709][ C1] rcu_dump_cpu_stacks+0x183/0x1cf [ 440.330878][ C1] ? find_next_bit+0x107/0x130 [ 440.335635][ C1] rcu_sched_clock_irq.cold+0x509/0xc0d [ 440.341362][ C1] ? raise_softirq+0x138/0x340 [ 440.346136][ C1] update_process_times+0x2d/0x70 [ 440.351254][ C1] tick_sched_handle+0xa2/0x190 [ 440.356155][ C1] tick_sched_timer+0x53/0x140 [ 440.360931][ C1] __hrtimer_run_queues+0x364/0xe40 [ 440.366160][ C1] ? tick_sched_do_timer+0x1b0/0x1b0 [ 440.371444][ C1] ? hrtimer_init+0x330/0x330 [ 440.376187][ C1] ? __sanitizer_cov_trace_cmp4+0x16/0x20 [ 440.381910][ C1] ? ktime_get_update_offsets_now+0x2ce/0x430 [ 440.387975][ C1] hrtimer_interrupt+0x314/0x770 [ 440.392971][ C1] smp_apic_timer_interrupt+0x160/0x610 [ 440.398535][ C1] apic_timer_interrupt+0xf/0x20 [ 440.403465][ C1] </IRQ> [ 440.406469][ C1] RIP: 0010:hash_ip4_del+0x1dd/0xce0 [ 440.411742][ C1] Code: 21 d3 e8 06 68 e5 fa 89 d8 49 8d 7c c7 10 48 89 85 68 ff ff ff 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 80 3c 02 00 <0f> 85 fd 09 00 00 48 8b 45 98 48 8b 8d 68 ff ff ff 48 8b 44 c8 10 [ 440.431371][ C1] RSP: 0018:ffffc90002076f10 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 440.439773][ C1] RAX: dffffc0000000000 RBX: 00000000000000ac RCX: 1ffffffff14f9ac6 [ 440.447744][ C1] RDX: 1ffff110139f60ae RSI: ffffffff867bcfd9 RDI: ffff88809cfb0570 [ 440.455730][ C1] RBP: ffffc90002076fb0 R08: ffff8880a2fc01c0 R09: ffffc90002076f28 [ 440.463703][ C1] R10: fffff5200040ede7 R11: ffffc90002076f3f R12: 0000000000000001 [ 440.471666][ C1] R13: 00000000ffffffff R14: ffffc90002077030 R15: ffff88809cfb0000 [ 440.479679][ C1] ? hash_ip4_del+0xb9/0xce0 [ 440.484325][ C1] hash_ip4_uadt+0x546/0x7a0 [ 440.488915][ C1] ? hash_ip6_del+0xe70/0xe70 [ 440.493615][ C1] ? hash_ip6_uadt+0x670/0x670 [ 440.498432][ C1] ? __kasan_check_write+0x14/0x20 [ 440.503542][ C1] call_ad+0x1a0/0x5a0 [ 440.507614][ C1] ? start_msg+0x220/0x220 [ 440.512092][ C1] ? nla_memcpy+0xb0/0xb0 [ 440.516418][ C1] ? __nla_parse+0x43/0x60 [ 440.520838][ C1] ip_set_ad.isra.0+0x572/0xb20 [ 440.525709][ C1] ? ip_set_nfnl_get_byindex+0x460/0x460 [ 440.531351][ C1] ? nla_memcpy+0xb0/0xb0 [ 440.535712][ C1] ? lock_downgrade+0x920/0x920 [ 440.540747][ C1] ip_set_udel+0x3a/0x50 [ 440.544989][ C1] ? ip_set_ad.isra.0+0xb20/0xb20 [ 440.550081][ C1] nfnetlink_rcv_msg+0xcf2/0xfb0 [ 440.555032][ C1] ? nfnetlink_bind+0x2c0/0x2c0 [ 440.559875][ C1] ? __kasan_check_read+0x11/0x20 [ 440.565088][ C1] ? __lock_acquire+0x8a0/0x4a00 [ 440.570058][ C1] ? save_stack+0x5c/0x90 [ 440.574419][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 440.580731][ C1] ? apparmor_capable+0x497/0x900 [ 440.585770][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 440.592010][ C1] ? __kasan_check_read+0x11/0x20 [ 440.597030][ C1] ? apparmor_cred_prepare+0x7b0/0x7b0 [ 440.602486][ C1] netlink_rcv_skb+0x177/0x450 [ 440.607306][ C1] ? nfnetlink_bind+0x2c0/0x2c0 [ 440.612233][ C1] ? netlink_ack+0xb50/0xb50 [ 440.616810][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 440.623781][ C1] ? ns_capable_common+0x93/0x100 [ 440.628879][ C1] ? ns_capable+0x20/0x30 [ 440.633194][ C1] ? __netlink_ns_capable+0x104/0x140 [ 440.638603][ C1] nfnetlink_rcv+0x1ba/0x460 [ 440.643184][ C1] ? nfnetlink_rcv_batch+0x17a0/0x17a0 [ 440.648641][ C1] ? netlink_deliver_tap+0x24a/0xbf0 [ 440.653927][ C1] ? __kasan_check_write+0x14/0x20 [ 440.659049][ C1] netlink_unicast+0x59e/0x7e0 [ 440.663850][ C1] ? netlink_attachskb+0x870/0x870 [ 440.669007][ C1] ? __sanitizer_cov_trace_cmp8+0x18/0x20 [ 440.674855][ C1] ? __check_object_size+0x3d/0x437 [ 440.680079][ C1] netlink_sendmsg+0x91c/0xea0 [ 440.684843][ C1] ? netlink_unicast+0x7e0/0x7e0 [ 440.689761][ C1] ? aa_sock_msg_perm.isra.0+0xba/0x170 [ 440.695292][ C1] ? apparmor_socket_sendmsg+0x2a/0x30 [ 440.700747][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 440.707256][ C1] ? security_socket_sendmsg+0x8d/0xc0 [ 440.712746][ C1] ? netlink_unicast+0x7e0/0x7e0 [ 440.717780][ C1] sock_sendmsg+0xd7/0x130 [ 440.722185][ C1] ____sys_sendmsg+0x753/0x880 [ 440.726947][ C1] ? kernel_sendmsg+0x50/0x50 [ 440.731820][ C1] ? __fget+0x35d/0x550 [ 440.735998][ C1] ? find_held_lock+0x35/0x130 [ 440.740755][ C1] ___sys_sendmsg+0x100/0x170 [ 440.745502][ C1] ? sendmsg_copy_msghdr+0x70/0x70 [ 440.750611][ C1] ? __kasan_check_read+0x11/0x20 [ 440.755633][ C1] ? __fget+0x37f/0x550 [ 440.759793][ C1] ? ksys_dup3+0x3e0/0x3e0 [ 440.764209][ C1] ? __fget_light+0x1a9/0x230 [ 440.768869][ C1] ? __fdget+0x1b/0x20 [ 440.772960][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 440.779297][ C1] __sys_sendmsg+0x105/0x1d0 [ 440.783874][ C1] ? __sys_sendmsg_sock+0xc0/0xc0 [ 440.788959][ C1] ? trace_hardirqs_on_thunk+0x1a/0x1c [ 440.794408][ C1] ? do_syscall_64+0x26/0x790 [ 440.799090][ C1] ? entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 440.805264][ C1] ? do_syscall_64+0x26/0x790 [ 440.809931][ C1] __x64_sys_sendmsg+0x78/0xb0 [ 440.814705][ C1] do_syscall_64+0xfa/0x790 [ 440.819205][ C1] entry_SYSCALL_64_after_hwframe+0x49/0xbe [ 440.825074][ C1] RIP: 0033:0x445b79 [ 440.828969][ C1] Code: e8 bc b7 02 00 48 83 c4 18 c3 0f 1f 80 00 00 00 00 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 2b 12 fc ff c3 66 2e 0f 1f 84 00 00 00 00 [ 440.848574][ C1] RSP: 002b:00007efe4b0bddb8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e [ 440.857008][ C1] RAX: ffffffffffffffda RBX: 00000000006dac28 RCX: 0000000000445b79 [ 440.864986][ C1] RDX: 0000000000000040 RSI: 0000000020000080 RDI: 0000000000000004 [ 440.873122][ C1] RBP: 00000000006dac20 R08: 0000000000000018 R09: 0000000000000000 [ 440.881092][ C1] R10: 0000000000000001 R11: 0000000000000246 R12: 00000000006dac2c [ 440.889249][ C1] R13: 00007ffe3e94402f R14: 00007efe4b0be9c0 R15: 20c49ba5e353f7cf