[ 36.625981][ T26] audit: type=1800 audit(1570192511.046:22): pid=7259 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="motd" dev="sda1" ino=2480 res=0 [ 36.666281][ T26] audit: type=1800 audit(1570192511.046:23): pid=7259 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="rsyslog" dev="sda1" ino=2475 res=0 [ 36.686295][ T26] audit: type=1800 audit(1570192511.056:24): pid=7259 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="sudo" dev="sda1" ino=2487 res=0 [....] 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. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.5' (ECDSA) to the list of known hosts. 2019/10/04 12:35:21 fuzzer started 2019/10/04 12:35:23 dialing manager at 10.128.0.105:38119 2019/10/04 12:35:23 syscalls: 2523 2019/10/04 12:35:23 code coverage: enabled 2019/10/04 12:35:23 comparison tracing: enabled 2019/10/04 12:35:23 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:35:23 setuid sandbox: enabled 2019/10/04 12:35:23 namespace sandbox: enabled 2019/10/04 12:35:23 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:35:23 fault injection: enabled 2019/10/04 12:35:23 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:35:23 net packet injection: enabled 2019/10/04 12:35:23 net device setup: enabled 2019/10/04 12:35:23 concurrency sanitizer: enabled syzkaller login: [ 50.980965][ T7413] ================================================================== [ 50.989168][ T7413] BUG: KCSAN: data-race in tcp_add_backlog+0x4a0/0xcc0 and tcp_grow_window.isra.0+0x6b/0x480 [ 50.999435][ T7413] [ 51.001748][ T7413] write to 0xffff8881220532ec of 4 bytes by interrupt on cpu 0: [ 51.009361][ T7413] tcp_add_backlog+0x4a0/0xcc0 [ 51.014108][ T7413] tcp_v4_rcv+0x1aba/0x1bf0 [ 51.018601][ T7413] ip_protocol_deliver_rcu+0x51/0x470 [ 51.024185][ T7413] ip_local_deliver_finish+0x110/0x140 [ 51.029631][ T7413] ip_local_deliver+0x133/0x210 [ 51.034528][ T7413] ip_rcv_finish+0x121/0x160 [ 51.039121][ T7413] ip_rcv+0x18f/0x1a0 [ 51.043206][ T7413] __netif_receive_skb_one_core+0xa7/0xe0 [ 51.048926][ T7413] __netif_receive_skb+0x37/0xf0 [ 51.053883][ T7413] netif_receive_skb_internal+0x59/0x190 [ 51.059493][ T7413] napi_gro_receive+0x28f/0x330 [ 51.064321][ T7413] receive_buf+0x284/0x30b0 [ 51.068805][ T7413] virtnet_poll+0x436/0x7d0 [ 51.073290][ T7413] net_rx_action+0x3ae/0xa50 [ 51.077853][ T7413] [ 51.080297][ T7413] read to 0xffff8881220532ec of 4 bytes by task 7413 on cpu 1: [ 51.088111][ T7413] tcp_grow_window.isra.0+0x6b/0x480 [ 51.093403][ T7413] tcp_event_data_recv+0x68f/0x990 [ 51.098557][ T7413] tcp_rcv_established+0xbfe/0xf50 [ 51.103699][ T7413] tcp_v4_do_rcv+0x381/0x4e0 [ 51.108275][ T7413] __release_sock+0x135/0x1e0 [ 51.113065][ T7413] release_sock+0x61/0x160 [ 51.117594][ T7413] tcp_recvmsg+0x63b/0x1a30 [ 51.122097][ T7413] inet_recvmsg+0xbb/0x250 [ 51.126499][ T7413] sock_recvmsg+0x92/0xb0 [ 51.130812][ T7413] sock_read_iter+0x15f/0x1e0 [ 51.135475][ T7413] new_sync_read+0x389/0x4f0 [ 51.140172][ T7413] __vfs_read+0xb1/0xc0 [ 51.144314][ T7413] vfs_read+0x143/0x2c0 [ 51.148454][ T7413] [ 51.150766][ T7413] Reported by Kernel Concurrency Sanitizer on: [ 51.156906][ T7413] CPU: 1 PID: 7413 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 51.164104][ T7413] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.174695][ T7413] ================================================================== [ 51.182815][ T7413] Kernel panic - not syncing: panic_on_warn set ... [ 51.190279][ T7413] CPU: 1 PID: 7413 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 51.197374][ T7413] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.207554][ T7413] Call Trace: [ 51.210897][ T7413] dump_stack+0xf5/0x159 [ 51.215120][ T7413] panic+0x209/0x639 [ 51.219322][ T7413] ? vprintk_func+0x8d/0x140 [ 51.224272][ T7413] kcsan_report.cold+0x57/0xeb [ 51.229250][ T7413] __kcsan_setup_watchpoint+0x342/0x500 [ 51.235170][ T7413] __tsan_read4+0x2c/0x30 [ 51.239559][ T7413] tcp_grow_window.isra.0+0x6b/0x480 [ 51.244887][ T7413] tcp_event_data_recv+0x68f/0x990 [ 51.250001][ T7413] tcp_rcv_established+0xbfe/0xf50 [ 51.256949][ T7413] ? ipv4_dst_check+0xc6/0xf0 [ 51.261629][ T7413] tcp_v4_do_rcv+0x381/0x4e0 [ 51.266965][ T7413] __release_sock+0x135/0x1e0 [ 51.271824][ T7413] release_sock+0x61/0x160 [ 51.276429][ T7413] tcp_recvmsg+0x63b/0x1a30 [ 51.281064][ T7413] inet_recvmsg+0xbb/0x250 [ 51.285490][ T7413] ? __tsan_read8+0x2c/0x30 [ 51.290166][ T7413] ? inet_sendpage+0x100/0x100 [ 51.295139][ T7413] sock_recvmsg+0x92/0xb0 [ 51.299505][ T7413] sock_read_iter+0x15f/0x1e0 [ 51.304171][ T7413] new_sync_read+0x389/0x4f0 [ 51.308926][ T7413] __vfs_read+0xb1/0xc0 [ 51.313080][ T7413] vfs_read+0x143/0x2c0 [ 51.317248][ T7413] ksys_read+0xd5/0x1b0 [ 51.321458][ T7413] __x64_sys_read+0x4c/0x60 [ 51.325964][ T7413] do_syscall_64+0xcf/0x2f0 [ 51.330578][ T7413] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 51.336456][ T7413] RIP: 0033:0x47c530 [ 51.340338][ T7413] 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 [ 51.360084][ T7413] RSP: 002b:000000c4203017d0 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 51.368481][ T7413] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 51.376452][ T7413] RDX: 0000000000001000 RSI: 000000c420316000 RDI: 0000000000000003 [ 51.384400][ T7413] RBP: 000000c420301828 R08: 0000000000000000 R09: 0000000000000000 [ 51.392349][ T7413] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000008 [ 51.400297][ T7413] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 51.409596][ T7413] Kernel Offset: disabled [ 51.413915][ T7413] Rebooting in 86400 seconds..