[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.614330][ T23] audit: type=1800 audit(1571742686.834:25): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 40.654426][ T23] audit: type=1800 audit(1571742686.844:26): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 40.674667][ T23] audit: type=1800 audit(1571742686.844:27): pid=7067 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2469 res=0 [....] Starting periodic command scheduler: cron[?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 '10.128.1.25' (ECDSA) to the list of known hosts. 2019/10/22 11:11:37 fuzzer started 2019/10/22 11:11:38 dialing manager at 10.128.0.105:37053 2019/10/22 11:11:38 syscalls: 2524 2019/10/22 11:11:38 code coverage: enabled 2019/10/22 11:11:38 comparison tracing: enabled 2019/10/22 11:11:38 extra coverage: extra coverage is not supported by the kernel 2019/10/22 11:11:38 setuid sandbox: enabled 2019/10/22 11:11:38 namespace sandbox: enabled 2019/10/22 11:11:38 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 11:11:38 fault injection: enabled 2019/10/22 11:11:38 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 11:11:38 net packet injection: enabled 2019/10/22 11:11:38 net device setup: enabled 2019/10/22 11:11:38 concurrency sanitizer: enabled syzkaller login: [ 53.045103][ C0] ================================================================== [ 53.053252][ C0] BUG: KCSAN: data-race in tick_sched_do_timer / tick_sched_do_timer [ 53.061300][ C0] [ 53.063627][ C0] write to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 1: [ 53.071288][ C0] tick_sched_do_timer+0xc0/0xe0 [ 53.076221][ C0] tick_sched_timer+0x43/0xe0 [ 53.080875][ C0] __hrtimer_run_queues+0x288/0x600 [ 53.086050][ C0] hrtimer_interrupt+0x22a/0x480 [ 53.090975][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 53.096411][ C0] apic_timer_interrupt+0xf/0x20 [ 53.101322][ C0] __kcsan_check_watchpoint+0xa2/0x180 [ 53.106753][ C0] __tsan_read1+0x15/0x30 [ 53.111061][ C0] __netif_receive_skb_core+0x20f/0x1a90 [ 53.116672][ C0] __netif_receive_skb_one_core+0x67/0xe0 [ 53.122369][ C0] __netif_receive_skb+0x37/0xf0 [ 53.127286][ C0] netif_receive_skb_internal+0x59/0x190 [ 53.132926][ C0] napi_gro_receive+0x28f/0x330 [ 53.137766][ C0] receive_buf+0x284/0x30b0 [ 53.142245][ C0] [ 53.144592][ C0] read to 0xffffffff85cb2790 of 4 bytes by interrupt on cpu 0: [ 53.152139][ C0] tick_sched_do_timer+0x33/0xe0 [ 53.157056][ C0] tick_sched_timer+0x43/0xe0 [ 53.161720][ C0] __hrtimer_run_queues+0x288/0x600 [ 53.166894][ C0] hrtimer_interrupt+0x22a/0x480 [ 53.171817][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 53.177250][ C0] apic_timer_interrupt+0xf/0x20 [ 53.182165][ C0] __kcsan_setup_watchpoint+0x3a/0x4a0 [ 53.187597][ C0] __tsan_read2+0x2c/0x30 [ 53.191987][ C0] ipt_do_table+0x5e7/0xe60 [ 53.196464][ C0] iptable_mangle_hook+0x7a/0x260 [ 53.201471][ C0] nf_hook_slow+0x83/0x160 [ 53.205870][ C0] ip_output+0x1d3/0x210 [ 53.210086][ C0] ip_local_out+0x74/0x90 [ 53.214383][ C0] [ 53.216684][ C0] Reported by Kernel Concurrency Sanitizer on: [ 53.222819][ C0] CPU: 0 PID: 7219 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 53.230268][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.240305][ C0] ================================================================== [ 53.248348][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 53.254912][ C0] CPU: 0 PID: 7219 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 53.262380][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.272451][ C0] Call Trace: [ 53.275710][ C0] [ 53.278560][ C0] dump_stack+0xf5/0x159 [ 53.282778][ C0] panic+0x210/0x640 [ 53.286651][ C0] ? ipt_do_table+0x5e7/0xe60 [ 53.291317][ C0] ? vprintk_func+0x8d/0x140 [ 53.295888][ C0] kcsan_report.cold+0xc/0x10 [ 53.300545][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 53.306068][ C0] __tsan_read4+0x2c/0x30 [ 53.310375][ C0] tick_sched_do_timer+0x33/0xe0 [ 53.315291][ C0] tick_sched_timer+0x43/0xe0 [ 53.319957][ C0] __hrtimer_run_queues+0x288/0x600 [ 53.325139][ C0] ? tick_sched_do_timer+0xe0/0xe0 [ 53.330237][ C0] hrtimer_interrupt+0x22a/0x480 [ 53.335163][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 53.340598][ C0] ? smp_reschedule_interrupt+0x71/0x1d0 [ 53.346209][ C0] apic_timer_interrupt+0xf/0x20 [ 53.351128][ C0] [ 53.354054][ C0] RIP: 0010:__kcsan_setup_watchpoint+0x3a/0x4a0 [ 53.360272][ C0] Code: 89 f4 53 89 d3 48 83 ec 18 66 0f 1f 44 00 00 65 8b 05 02 a2 ae 7e a9 00 01 1f 00 0f 85 4e 02 00 00 65 48 8b 04 25 40 6c 01 00 <8b> 90 ec 09 00 00 48 05 e8 09 00 00 85 d2 0f 8f 4b 02 00 00 8b 50 [ 53.379863][ C0] RSP: 0018:ffffc90001c175a8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 53.388257][ C0] RAX: ffff88811d2eb000 RBX: 0000000000000000 RCX: 0000000000000003 [ 53.396290][ C0] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff888129326ef8 [ 53.404239][ C0] RBP: ffffc90001c175e8 R08: 0000000000000000 R09: 0000888129326ef9 [ 53.412195][ C0] R10: 00000000aaaaaaab R11: ffffffff86045d48 R12: 0000000000000002 [ 53.420156][ C0] R13: 0000000000000000 R14: ffff888129326ef8 R15: ffff888129326ea0 [ 53.428131][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 53.433750][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 53.439979][ C0] ? __sanitizer_cov_trace_switch+0x49/0x80 [ 53.445851][ C0] __tsan_read2+0x2c/0x30 [ 53.450156][ C0] ipt_do_table+0x5e7/0xe60 [ 53.454636][ C0] ? __tsan_read1+0x2c/0x30 [ 53.459115][ C0] ? __sanitizer_cov_trace_const_cmp1+0x1a/0x20 [ 53.465348][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 53.470956][ C0] iptable_mangle_hook+0x7a/0x260 [ 53.475953][ C0] ? __tsan_read4+0x2c/0x30 [ 53.480433][ C0] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 53.486652][ C0] nf_hook_slow+0x83/0x160 [ 53.491047][ C0] ? iptable_mangle_net_exit+0xa0/0xa0 [ 53.496484][ C0] ip_output+0x1d3/0x210 [ 53.500713][ C0] ? __ip_finish_output+0x490/0x490 [ 53.505914][ C0] ip_local_out+0x74/0x90 [ 53.510219][ C0] __ip_queue_xmit+0x3a8/0xa40 [ 53.514966][ C0] ip_queue_xmit+0x45/0x60 [ 53.519361][ C0] __tcp_transmit_skb+0xe81/0x1d60 [ 53.524464][ C0] __tcp_send_ack+0x246/0x300 [ 53.529116][ C0] tcp_send_ack+0x34/0x40 [ 53.533421][ C0] tcp_cleanup_rbuf+0x130/0x360 [ 53.538253][ C0] tcp_recvmsg+0x633/0x1a30 [ 53.542749][ C0] inet_recvmsg+0xbb/0x250 [ 53.547152][ C0] ? __tsan_read8+0x2c/0x30 [ 53.551643][ C0] ? inet_sendpage+0x100/0x100 [ 53.556387][ C0] sock_recvmsg+0x92/0xb0 [ 53.560692][ C0] sock_read_iter+0x15f/0x1e0 [ 53.565350][ C0] new_sync_read+0x389/0x4f0 [ 53.569929][ C0] __vfs_read+0xb1/0xc0 [ 53.574064][ C0] vfs_read+0x143/0x2c0 [ 53.578199][ C0] ksys_read+0xd5/0x1b0 [ 53.582334][ C0] __x64_sys_read+0x4c/0x60 [ 53.586829][ C0] do_syscall_64+0xcc/0x370 [ 53.591312][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 53.597177][ C0] RIP: 0033:0x47c530 [ 53.601053][ C0] Code: 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 49 c7 c2 00 00 00 00 49 c7 c0 00 00 00 00 49 c7 c1 00 00 00 00 48 8b 44 24 08 0f 05 <48> 3d 01 f0 ff ff 76 20 48 c7 44 24 28 ff ff ff ff 48 c7 44 24 30 [ 53.620815][ C0] RSP: 002b:000000c4204e37d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 53.629200][ C0] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 53.637409][ C0] RDX: 0000000000001000 RSI: 000000c4200aa000 RDI: 0000000000000003 [ 53.645369][ C0] RBP: 000000c4204e3830 R08: 0000000000000000 R09: 0000000000000000 [ 53.653327][ C0] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000080 [ 53.661278][ C0] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 53.670419][ C0] Kernel Offset: disabled [ 53.674737][ C0] Rebooting in 86400 seconds..