[ 37.968451][ T26] audit: type=1800 audit(1571778164.187:24): pid=7090 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. [ 38.520867][ T26] audit: type=1800 audit(1571778164.817:25): pid=7090 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 38.564070][ T26] audit: type=1800 audit(1571778164.817:26): pid=7090 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 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 '10.128.0.206' (ECDSA) to the list of known hosts. 2019/10/22 21:02:55 fuzzer started 2019/10/22 21:02:57 dialing manager at 10.128.0.105:33369 2019/10/22 21:02:57 syscalls: 2524 2019/10/22 21:02:57 code coverage: enabled 2019/10/22 21:02:57 comparison tracing: enabled 2019/10/22 21:02:57 extra coverage: extra coverage is not supported by the kernel 2019/10/22 21:02:57 setuid sandbox: enabled 2019/10/22 21:02:57 namespace sandbox: enabled 2019/10/22 21:02:57 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 21:02:57 fault injection: enabled 2019/10/22 21:02:57 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 21:02:57 net packet injection: enabled 2019/10/22 21:02:57 net device setup: enabled 2019/10/22 21:02:57 concurrency sanitizer: enabled syzkaller login: [ 51.706572][ T7261] ================================================================== [ 51.714724][ T7261] BUG: KCSAN: data-race in __tcp_select_window / tcp_add_backlog [ 51.722424][ T7261] [ 51.724753][ T7261] write to 0xffff8881221352ec of 4 bytes by interrupt on cpu 1: [ 51.732376][ T7261] tcp_add_backlog+0x4a0/0xcc0 [ 51.737330][ T7261] tcp_v4_rcv+0x1a60/0x1bb0 [ 51.741824][ T7261] ip_protocol_deliver_rcu+0x4d/0x420 [ 51.747174][ T7261] ip_local_deliver_finish+0x110/0x140 [ 51.752625][ T7261] ip_local_deliver+0x133/0x210 [ 51.757458][ T7261] ip_rcv_finish+0x121/0x160 [ 51.762023][ T7261] ip_rcv+0x18f/0x1a0 [ 51.766000][ T7261] __netif_receive_skb_one_core+0xa7/0xe0 [ 51.771705][ T7261] __netif_receive_skb+0x37/0xf0 [ 51.776662][ T7261] netif_receive_skb_internal+0x59/0x190 [ 51.782286][ T7261] napi_gro_receive+0x28f/0x330 [ 51.787112][ T7261] receive_buf+0x284/0x30b0 [ 51.791604][ T7261] virtnet_poll+0x436/0x7d0 [ 51.796108][ T7261] net_rx_action+0x3ae/0xa90 [ 51.800675][ T7261] [ 51.802997][ T7261] read to 0xffff8881221352ec of 4 bytes by task 7261 on cpu 0: [ 51.810523][ T7261] __tcp_select_window+0x6b/0x4d0 [ 51.815522][ T7261] __tcp_transmit_skb+0x700/0x1d60 [ 51.820790][ T7261] __tcp_send_ack+0x246/0x300 [ 51.825457][ T7261] tcp_send_ack+0x34/0x40 [ 51.829864][ T7261] tcp_cleanup_rbuf+0x130/0x360 [ 51.834851][ T7261] tcp_recvmsg+0x633/0x1a30 [ 51.839448][ T7261] inet_recvmsg+0xbb/0x250 [ 51.843868][ T7261] sock_recvmsg+0x92/0xb0 [ 51.848546][ T7261] sock_read_iter+0x15f/0x1e0 [ 51.853223][ T7261] new_sync_read+0x389/0x4f0 [ 51.858009][ T7261] __vfs_read+0xb1/0xc0 [ 51.862143][ T7261] vfs_read+0x143/0x2c0 [ 51.866276][ T7261] ksys_read+0xd5/0x1b0 [ 51.870577][ T7261] [ 51.872892][ T7261] Reported by Kernel Concurrency Sanitizer on: [ 51.879042][ T7261] CPU: 0 PID: 7261 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 51.886470][ T7261] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.896545][ T7261] ================================================================== [ 51.904583][ T7261] Kernel panic - not syncing: panic_on_warn set ... [ 51.911146][ T7261] CPU: 0 PID: 7261 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 51.918586][ T7261] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 51.928766][ T7261] Call Trace: [ 51.932277][ T7261] dump_stack+0xf5/0x159 [ 51.936553][ T7261] panic+0x210/0x640 [ 51.940546][ T7261] ? sock_read_iter+0x15f/0x1e0 [ 51.945552][ T7261] ? vprintk_func+0x8d/0x140 [ 51.950151][ T7261] kcsan_report.cold+0xc/0x10 [ 51.954819][ T7261] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 51.960370][ T7261] __tsan_read4+0x2c/0x30 [ 51.964704][ T7261] __tcp_select_window+0x6b/0x4d0 [ 51.969739][ T7261] __tcp_transmit_skb+0x700/0x1d60 [ 51.975271][ T7261] __tcp_send_ack+0x246/0x300 [ 51.980009][ T7261] tcp_send_ack+0x34/0x40 [ 51.984332][ T7261] tcp_cleanup_rbuf+0x130/0x360 [ 51.989180][ T7261] tcp_recvmsg+0x633/0x1a30 [ 51.993679][ T7261] inet_recvmsg+0xbb/0x250 [ 51.998175][ T7261] ? __tsan_read8+0x2c/0x30 [ 52.003614][ T7261] ? inet_sendpage+0x100/0x100 [ 52.008546][ T7261] sock_recvmsg+0x92/0xb0 [ 52.013547][ T7261] sock_read_iter+0x15f/0x1e0 [ 52.019060][ T7261] new_sync_read+0x389/0x4f0 [ 52.023824][ T7261] __vfs_read+0xb1/0xc0 [ 52.028061][ T7261] vfs_read+0x143/0x2c0 [ 52.032218][ T7261] ksys_read+0xd5/0x1b0 [ 52.036353][ T7261] __x64_sys_read+0x4c/0x60 [ 52.040860][ T7261] do_syscall_64+0xcc/0x370 [ 52.045356][ T7261] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 52.051501][ T7261] RIP: 0033:0x47c530 [ 52.055402][ T7261] 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 [ 52.074995][ T7261] RSP: 002b:000000c4204df7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 52.083412][ T7261] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 52.091386][ T7261] RDX: 0000000000001000 RSI: 000000c420158000 RDI: 0000000000000003 [ 52.100398][ T7261] RBP: 000000c4204df830 R08: 0000000000000000 R09: 0000000000000000 [ 52.108361][ T7261] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000020 [ 52.116308][ T7261] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 52.125660][ T7261] Kernel Offset: disabled [ 52.130050][ T7261] Rebooting in 86400 seconds..