[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.045257][ T25] audit: type=1800 audit(1571740958.395:25): pid=7069 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.080393][ T25] audit: type=1800 audit(1571740958.395:26): pid=7069 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.103401][ T25] audit: type=1800 audit(1571740958.405:27): pid=7069 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 '10.128.10.9' (ECDSA) to the list of known hosts. 2019/10/22 10:42:47 fuzzer started 2019/10/22 10:42:49 dialing manager at 10.128.0.105:37053 2019/10/22 10:42:49 syscalls: 2524 2019/10/22 10:42:49 code coverage: enabled 2019/10/22 10:42:49 comparison tracing: enabled 2019/10/22 10:42:49 extra coverage: extra coverage is not supported by the kernel 2019/10/22 10:42:49 setuid sandbox: enabled 2019/10/22 10:42:49 namespace sandbox: enabled 2019/10/22 10:42:49 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 10:42:49 fault injection: enabled 2019/10/22 10:42:49 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 10:42:49 net packet injection: enabled 2019/10/22 10:42:49 net device setup: enabled 2019/10/22 10:42:49 concurrency sanitizer: enabled syzkaller login: [ 45.462194][ T7226] ================================================================== [ 45.470327][ T7226] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 45.478805][ T7226] [ 45.481116][ T7226] read to 0xffff8881238d6308 of 4 bytes by interrupt on cpu 1: [ 45.488641][ T7226] __nf_conntrack_find_get+0x284/0x880 [ 45.494088][ T7226] nf_conntrack_in+0x2ef/0xa80 [ 45.498823][ T7226] ipv4_conntrack_in+0x27/0x40 [ 45.503564][ T7226] nf_hook_slow+0x83/0x160 [ 45.507952][ T7226] ip_rcv+0x12f/0x1a0 [ 45.511950][ T7226] __netif_receive_skb_one_core+0xa7/0xe0 [ 45.517645][ T7226] __netif_receive_skb+0x37/0xf0 [ 45.522575][ T7226] netif_receive_skb_internal+0x59/0x190 [ 45.528191][ T7226] napi_gro_receive+0x28f/0x330 [ 45.533018][ T7226] receive_buf+0x284/0x30b0 [ 45.537496][ T7226] virtnet_poll+0x436/0x7d0 [ 45.541972][ T7226] net_rx_action+0x3ae/0xa90 [ 45.546552][ T7226] __do_softirq+0x115/0x33f [ 45.551029][ T7226] run_ksoftirqd+0x46/0x60 [ 45.555410][ T7226] [ 45.557718][ T7226] write to 0xffff8881238d6308 of 4 bytes by task 7226 on cpu 0: [ 45.565322][ T7226] __nf_ct_refresh_acct+0xfb/0x1b0 [ 45.570410][ T7226] nf_conntrack_tcp_packet+0xd40/0x3390 [ 45.575930][ T7226] nf_conntrack_in+0x410/0xa80 [ 45.580669][ T7226] ipv4_conntrack_local+0xbe/0x130 [ 45.585755][ T7226] nf_hook_slow+0x83/0x160 [ 45.590159][ T7226] __ip_local_out+0x1f7/0x2b0 [ 45.594810][ T7226] ip_local_out+0x31/0x90 [ 45.599112][ T7226] __ip_queue_xmit+0x3a8/0xa40 [ 45.603862][ T7226] ip_queue_xmit+0x45/0x60 [ 45.608304][ T7226] __tcp_transmit_skb+0xe81/0x1d60 [ 45.613399][ T7226] __tcp_send_ack+0x246/0x300 [ 45.618054][ T7226] tcp_send_ack+0x34/0x40 [ 45.622364][ T7226] tcp_cleanup_rbuf+0x130/0x360 [ 45.627181][ T7226] [ 45.629484][ T7226] Reported by Kernel Concurrency Sanitizer on: [ 45.635615][ T7226] CPU: 0 PID: 7226 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.643053][ T7226] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.653082][ T7226] ================================================================== [ 45.661119][ T7226] Kernel panic - not syncing: panic_on_warn set ... [ 45.667690][ T7226] CPU: 0 PID: 7226 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.675115][ T7226] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.685144][ T7226] Call Trace: [ 45.688454][ T7226] dump_stack+0xf5/0x159 [ 45.692671][ T7226] panic+0x210/0x640 [ 45.696542][ T7226] ? ip_queue_xmit+0x45/0x60 [ 45.701107][ T7226] ? vprintk_func+0x8d/0x140 [ 45.705682][ T7226] kcsan_report.cold+0xc/0x10 [ 45.710376][ T7226] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 45.715902][ T7226] __tsan_write4+0x32/0x40 [ 45.720310][ T7226] __nf_ct_refresh_acct+0xfb/0x1b0 [ 45.725406][ T7226] nf_conntrack_tcp_packet+0xd40/0x3390 [ 45.730936][ T7226] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 45.736550][ T7226] nf_conntrack_in+0x410/0xa80 [ 45.741296][ T7226] ipv4_conntrack_local+0xbe/0x130 [ 45.746386][ T7226] nf_hook_slow+0x83/0x160 [ 45.750779][ T7226] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 45.755522][ T7226] __ip_local_out+0x1f7/0x2b0 [ 45.760184][ T7226] ? constant_test_bit+0x30/0x30 [ 45.765108][ T7226] ip_local_out+0x31/0x90 [ 45.769427][ T7226] __ip_queue_xmit+0x3a8/0xa40 [ 45.774189][ T7226] ip_queue_xmit+0x45/0x60 [ 45.778849][ T7226] __tcp_transmit_skb+0xe81/0x1d60 [ 45.783953][ T7226] __tcp_send_ack+0x246/0x300 [ 45.788617][ T7226] tcp_send_ack+0x34/0x40 [ 45.792926][ T7226] tcp_cleanup_rbuf+0x130/0x360 [ 45.797752][ T7226] tcp_recvmsg+0x633/0x1a30 [ 45.802252][ T7226] inet_recvmsg+0xbb/0x250 [ 45.806650][ T7226] ? __tsan_read8+0x2c/0x30 [ 45.811130][ T7226] ? inet_sendpage+0x100/0x100 [ 45.815875][ T7226] sock_recvmsg+0x92/0xb0 [ 45.820182][ T7226] sock_read_iter+0x15f/0x1e0 [ 45.824839][ T7226] new_sync_read+0x389/0x4f0 [ 45.829410][ T7226] __vfs_read+0xb1/0xc0 [ 45.833555][ T7226] vfs_read+0x143/0x2c0 [ 45.837688][ T7226] ksys_read+0xd5/0x1b0 [ 45.841824][ T7226] __x64_sys_read+0x4c/0x60 [ 45.846307][ T7226] do_syscall_64+0xcc/0x370 [ 45.850801][ T7226] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.856666][ T7226] RIP: 0033:0x47c530 [ 45.860550][ T7226] 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 [ 45.880672][ T7226] RSP: 002b:000000c420307810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 45.889055][ T7226] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 45.897000][ T7226] RDX: 0000000000001000 RSI: 000000c42031a000 RDI: 0000000000000003 [ 45.904945][ T7226] RBP: 000000c420307868 R08: 0000000000000000 R09: 0000000000000000 [ 45.912898][ T7226] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000100 [ 45.920854][ T7226] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 45.930045][ T7226] Kernel Offset: disabled [ 45.934402][ T7226] Rebooting in 86400 seconds..