[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.539190][ T25] audit: type=1800 audit(1570192125.813:25): pid=7065 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 40.566635][ T25] audit: type=1800 audit(1570192125.813:26): pid=7065 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 40.593520][ T25] audit: type=1800 audit(1570192125.813:27): pid=7065 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 '10.128.0.243' (ECDSA) to the list of known hosts. 2019/10/04 12:28:56 fuzzer started 2019/10/04 12:28:57 dialing manager at 10.128.0.105:38119 2019/10/04 12:28:58 syscalls: 2523 2019/10/04 12:28:58 code coverage: enabled 2019/10/04 12:28:58 comparison tracing: enabled 2019/10/04 12:28:58 extra coverage: extra coverage is not supported by the kernel 2019/10/04 12:28:58 setuid sandbox: enabled 2019/10/04 12:28:58 namespace sandbox: enabled 2019/10/04 12:28:58 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/04 12:28:58 fault injection: enabled 2019/10/04 12:28:58 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/04 12:28:58 net packet injection: enabled 2019/10/04 12:28:58 net device setup: enabled 2019/10/04 12:28:58 concurrency sanitizer: enabled syzkaller login: [ 52.827541][ T7229] ================================================================== [ 52.835783][ T7229] BUG: KCSAN: data-race in tcp_add_backlog+0x4a0/0xcc0 and tcp_grow_window.isra.0+0x6b/0x480 [ 52.845913][ T7229] [ 52.848236][ T7229] write to 0xffff88811ee2a12c of 4 bytes by interrupt on cpu 0: [ 52.855854][ T7229] tcp_add_backlog+0x4a0/0xcc0 [ 52.860596][ T7229] tcp_v4_rcv+0x1aba/0x1bf0 [ 52.865074][ T7229] ip_protocol_deliver_rcu+0x51/0x470 [ 52.870423][ T7229] ip_local_deliver_finish+0x110/0x140 [ 52.875857][ T7229] ip_local_deliver+0x133/0x210 [ 52.880682][ T7229] ip_rcv_finish+0x121/0x160 [ 52.885251][ T7229] ip_rcv+0x18f/0x1a0 [ 52.889221][ T7229] __netif_receive_skb_one_core+0xa7/0xe0 [ 52.894920][ T7229] __netif_receive_skb+0x37/0xf0 [ 52.899836][ T7229] netif_receive_skb_internal+0x59/0x190 [ 52.905448][ T7229] napi_gro_receive+0x28f/0x330 [ 52.913871][ T7229] receive_buf+0x284/0x30b0 [ 52.918876][ T7229] virtnet_poll+0x436/0x7d0 [ 52.923371][ T7229] net_rx_action+0x3ae/0xa50 [ 52.927947][ T7229] [ 52.930273][ T7229] read to 0xffff88811ee2a12c of 4 bytes by task 7229 on cpu 1: [ 52.937808][ T7229] tcp_grow_window.isra.0+0x6b/0x480 [ 52.943093][ T7229] tcp_event_data_recv+0x68f/0x990 [ 52.948200][ T7229] tcp_rcv_established+0xbfe/0xf50 [ 52.953414][ T7229] tcp_v4_do_rcv+0x381/0x4e0 [ 52.957987][ T7229] __release_sock+0x135/0x1e0 [ 52.962655][ T7229] release_sock+0x61/0x160 [ 52.967072][ T7229] tcp_recvmsg+0x63b/0x1a30 [ 52.972130][ T7229] inet_recvmsg+0xbb/0x250 [ 52.976522][ T7229] sock_recvmsg+0x92/0xb0 [ 52.981707][ T7229] sock_read_iter+0x15f/0x1e0 [ 52.986367][ T7229] new_sync_read+0x389/0x4f0 [ 52.990938][ T7229] __vfs_read+0xb1/0xc0 [ 52.995069][ T7229] vfs_read+0x143/0x2c0 [ 52.999213][ T7229] [ 53.001536][ T7229] Reported by Kernel Concurrency Sanitizer on: [ 53.007678][ T7229] CPU: 1 PID: 7229 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 53.014760][ T7229] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.024804][ T7229] ================================================================== [ 53.032990][ T7229] Kernel panic - not syncing: panic_on_warn set ... [ 53.039574][ T7229] CPU: 1 PID: 7229 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 53.046666][ T7229] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.056697][ T7229] Call Trace: [ 53.059973][ T7229] dump_stack+0xf5/0x159 [ 53.064209][ T7229] panic+0x209/0x639 [ 53.068277][ T7229] ? vprintk_func+0x8d/0x140 [ 53.073323][ T7229] kcsan_report.cold+0x57/0xeb [ 53.078071][ T7229] __kcsan_setup_watchpoint+0x342/0x500 [ 53.083699][ T7229] __tsan_read4+0x2c/0x30 [ 53.088016][ T7229] tcp_grow_window.isra.0+0x6b/0x480 [ 53.093295][ T7229] tcp_event_data_recv+0x68f/0x990 [ 53.098392][ T7229] tcp_rcv_established+0xbfe/0xf50 [ 53.103547][ T7229] ? ipv4_dst_check+0xc6/0xf0 [ 53.108210][ T7229] tcp_v4_do_rcv+0x381/0x4e0 [ 53.112832][ T7229] __release_sock+0x135/0x1e0 [ 53.117506][ T7229] release_sock+0x61/0x160 [ 53.122423][ T7229] tcp_recvmsg+0x63b/0x1a30 [ 53.126916][ T7229] ? debug_smp_processor_id+0x4c/0x172 [ 53.132360][ T7229] inet_recvmsg+0xbb/0x250 [ 53.136753][ T7229] ? __tsan_read8+0x2c/0x30 [ 53.141238][ T7229] ? inet_sendpage+0x100/0x100 [ 53.145989][ T7229] sock_recvmsg+0x92/0xb0 [ 53.150310][ T7229] sock_read_iter+0x15f/0x1e0 [ 53.154985][ T7229] new_sync_read+0x389/0x4f0 [ 53.159559][ T7229] __vfs_read+0xb1/0xc0 [ 53.163710][ T7229] vfs_read+0x143/0x2c0 [ 53.167844][ T7229] ksys_read+0xd5/0x1b0 [ 53.171982][ T7229] __x64_sys_read+0x4c/0x60 [ 53.176475][ T7229] do_syscall_64+0xcf/0x2f0 [ 53.181019][ T7229] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 53.186890][ T7229] RIP: 0033:0x47c530 [ 53.190764][ T7229] 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 [ 53.210391][ T7229] RSP: 002b:000000c42039f7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 53.218792][ T7229] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 53.226740][ T7229] RDX: 0000000000001000 RSI: 000000c420136000 RDI: 0000000000000003 [ 53.234689][ T7229] RBP: 000000c42039f830 R08: 0000000000000000 R09: 0000000000000000 [ 53.242649][ T7229] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000200 [ 53.250632][ T7229] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 53.259903][ T7229] Kernel Offset: disabled [ 53.264252][ T7229] Rebooting in 86400 seconds..