[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.164829][ T26] audit: type=1800 audit(1572633008.197:25): pid=6991 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.191933][ T26] audit: type=1800 audit(1572633008.207:26): pid=6991 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.231635][ T26] audit: type=1800 audit(1572633008.207:27): pid=6991 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 '10.128.15.211' (ECDSA) to the list of known hosts. 2019/11/01 18:30:15 fuzzer started 2019/11/01 18:30:16 dialing manager at 10.128.0.105:41349 2019/11/01 18:30:16 syscalls: 2540 2019/11/01 18:30:16 code coverage: enabled 2019/11/01 18:30:16 comparison tracing: enabled 2019/11/01 18:30:16 extra coverage: extra coverage is not supported by the kernel 2019/11/01 18:30:16 setuid sandbox: enabled 2019/11/01 18:30:16 namespace sandbox: enabled 2019/11/01 18:30:16 Android sandbox: /sys/fs/selinux/policy does not exist 2019/11/01 18:30:16 fault injection: enabled 2019/11/01 18:30:16 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/11/01 18:30:16 net packet injection: enabled 2019/11/01 18:30:16 net device setup: enabled 2019/11/01 18:30:16 concurrency sanitizer: enabled 2019/11/01 18:30:18 adding functions to KCSAN blacklist: 'tick_do_update_jiffies64' 'ep_poll' 'tcp_add_backlog' 'pid_update_inode' 'tomoyo_supervisor' '__hrtimer_run_queues' syzkaller login: [ 46.026176][ T7147] ================================================================== [ 46.034333][ T7147] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 46.042802][ T7147] [ 46.045112][ T7147] read to 0xffff888122b87108 of 4 bytes by interrupt on cpu 0: [ 46.052634][ T7147] __nf_conntrack_find_get+0x284/0x880 [ 46.058072][ T7147] nf_conntrack_in+0x2ef/0xa80 [ 46.062817][ T7147] ipv4_conntrack_in+0x27/0x40 [ 46.067596][ T7147] nf_hook_slow+0x83/0x160 [ 46.072024][ T7147] ip_rcv+0x12f/0x1a0 [ 46.075999][ T7147] __netif_receive_skb_one_core+0xa7/0xe0 [ 46.081734][ T7147] __netif_receive_skb+0x37/0xf0 [ 46.086658][ T7147] netif_receive_skb_internal+0x59/0x190 [ 46.092277][ T7147] napi_gro_receive+0x28f/0x330 [ 46.097123][ T7147] receive_buf+0x284/0x30b0 [ 46.101617][ T7147] virtnet_poll+0x436/0x7d0 [ 46.106111][ T7147] net_rx_action+0x3ae/0xa90 [ 46.110691][ T7147] __do_softirq+0x115/0x33f [ 46.115173][ T7147] irq_exit+0xbb/0xe0 [ 46.119127][ T7147] [ 46.121445][ T7147] write to 0xffff888122b87108 of 4 bytes by task 7147 on cpu 1: [ 46.129147][ T7147] __nf_ct_refresh_acct+0xfb/0x1b0 [ 46.134245][ T7147] nf_conntrack_tcp_packet+0xd40/0x3390 [ 46.139805][ T7147] nf_conntrack_in+0x410/0xa80 [ 46.144544][ T7147] ipv4_conntrack_local+0xbe/0x130 [ 46.149631][ T7147] nf_hook_slow+0x83/0x160 [ 46.154036][ T7147] __ip_local_out+0x1f7/0x2b0 [ 46.158688][ T7147] ip_local_out+0x31/0x90 [ 46.163006][ T7147] __ip_queue_xmit+0x3a8/0xa40 [ 46.167748][ T7147] ip_queue_xmit+0x45/0x60 [ 46.172171][ T7147] __tcp_transmit_skb+0xe81/0x1d60 [ 46.177259][ T7147] __tcp_send_ack+0x246/0x300 [ 46.181969][ T7147] tcp_send_ack+0x34/0x40 [ 46.186282][ T7147] __tcp_ack_snd_check+0xd9/0x4f0 [ 46.191276][ T7147] [ 46.193584][ T7147] Reported by Kernel Concurrency Sanitizer on: [ 46.199733][ T7147] CPU: 1 PID: 7147 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 46.207162][ T7147] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.217204][ T7147] ================================================================== [ 46.225238][ T7147] Kernel panic - not syncing: panic_on_warn set ... [ 46.231811][ T7147] CPU: 1 PID: 7147 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 46.239249][ T7147] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.249281][ T7147] Call Trace: [ 46.252559][ T7147] dump_stack+0xf5/0x159 [ 46.256783][ T7147] panic+0x210/0x640 [ 46.260674][ T7147] ? ip_queue_xmit+0x45/0x60 [ 46.265706][ T7147] ? vprintk_func+0x8d/0x140 [ 46.270275][ T7147] kcsan_report.cold+0xc/0x10 [ 46.274930][ T7147] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 46.280544][ T7147] ? pfifo_fast_dequeue+0x3d1/0x6e0 [ 46.285718][ T7147] __tsan_write4+0x32/0x40 [ 46.290116][ T7147] __nf_ct_refresh_acct+0xfb/0x1b0 [ 46.295208][ T7147] nf_conntrack_tcp_packet+0xd40/0x3390 [ 46.300741][ T7147] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 46.306356][ T7147] nf_conntrack_in+0x410/0xa80 [ 46.311109][ T7147] ipv4_conntrack_local+0xbe/0x130 [ 46.316203][ T7147] nf_hook_slow+0x83/0x160 [ 46.320595][ T7147] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 46.325339][ T7147] __ip_local_out+0x1f7/0x2b0 [ 46.329995][ T7147] ? constant_test_bit+0x30/0x30 [ 46.334917][ T7147] ip_local_out+0x31/0x90 [ 46.339226][ T7147] __ip_queue_xmit+0x3a8/0xa40 [ 46.344346][ T7147] ip_queue_xmit+0x45/0x60 [ 46.348760][ T7147] __tcp_transmit_skb+0xe81/0x1d60 [ 46.353875][ T7147] __tcp_send_ack+0x246/0x300 [ 46.358546][ T7147] tcp_send_ack+0x34/0x40 [ 46.362878][ T7147] __tcp_ack_snd_check+0xd9/0x4f0 [ 46.367926][ T7147] tcp_rcv_established+0xce9/0xf50 [ 46.373070][ T7147] ? ipv4_dst_check+0xc6/0xf0 [ 46.377731][ T7147] tcp_v4_do_rcv+0x381/0x4e0 [ 46.382303][ T7147] __release_sock+0x135/0x1e0 [ 46.387075][ T7147] release_sock+0x61/0x160 [ 46.391503][ T7147] tcp_recvmsg+0x63b/0x1a30 [ 46.396002][ T7147] inet_recvmsg+0xbb/0x250 [ 46.400401][ T7147] ? __tsan_read8+0x2c/0x30 [ 46.404902][ T7147] ? inet_sendpage+0x100/0x100 [ 46.409645][ T7147] sock_recvmsg+0x92/0xb0 [ 46.413952][ T7147] sock_read_iter+0x15f/0x1e0 [ 46.418621][ T7147] new_sync_read+0x389/0x4f0 [ 46.423202][ T7147] __vfs_read+0xb1/0xc0 [ 46.427337][ T7147] vfs_read+0x143/0x2c0 [ 46.431471][ T7147] ksys_read+0xd5/0x1b0 [ 46.435607][ T7147] __x64_sys_read+0x4c/0x60 [ 46.440088][ T7147] do_syscall_64+0xcc/0x370 [ 46.444569][ T7147] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.450435][ T7147] RIP: 0033:0x47c530 [ 46.454307][ T7147] 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 [ 46.473885][ T7147] RSP: 002b:000000c4204db810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 46.482269][ T7147] RAX: ffffffffffffffda RBX: 000000c420041000 RCX: 000000000047c530 [ 46.490227][ T7147] RDX: 0000000000001000 RSI: 000000c4200aa000 RDI: 0000000000000003 [ 46.498178][ T7147] RBP: 000000c4204db868 R08: 0000000000000000 R09: 0000000000000000 [ 46.506136][ T7147] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002 [ 46.514082][ T7147] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 46.523263][ T7147] Kernel Offset: disabled [ 46.527592][ T7147] Rebooting in 86400 seconds..