[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 41.475812][ T25] audit: type=1800 audit(1570571793.741:25): pid=7048 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 41.495758][ T25] audit: type=1800 audit(1570571793.741:26): pid=7048 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 41.515953][ T25] audit: type=1800 audit(1570571793.741:27): pid=7048 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 '10.128.0.226' (ECDSA) to the list of known hosts. 2019/10/08 21:56:43 fuzzer started 2019/10/08 21:56:45 dialing manager at 10.128.0.105:35069 2019/10/08 21:56:45 syscalls: 2523 2019/10/08 21:56:45 code coverage: enabled 2019/10/08 21:56:45 comparison tracing: enabled 2019/10/08 21:56:45 extra coverage: extra coverage is not supported by the kernel 2019/10/08 21:56:45 setuid sandbox: enabled 2019/10/08 21:56:45 namespace sandbox: enabled 2019/10/08 21:56:45 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/08 21:56:45 fault injection: enabled 2019/10/08 21:56:45 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/08 21:56:45 net packet injection: enabled 2019/10/08 21:56:45 net device setup: enabled 2019/10/08 21:56:45 concurrency sanitizer: enabled syzkaller login: [ 53.215525][ T7208] ================================================================== [ 53.223651][ T7208] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 53.231423][ T7208] [ 53.233735][ T7208] read to 0xffff88811e968a0c of 4 bytes by interrupt on cpu 0: [ 53.241300][ T7208] tcp_add_backlog+0x43/0xcc0 [ 53.245989][ T7208] tcp_v4_rcv+0x1aba/0x1bf0 [ 53.250484][ T7208] ip_protocol_deliver_rcu+0x51/0x470 [ 53.255855][ T7208] ip_local_deliver_finish+0x110/0x140 [ 53.261409][ T7208] ip_local_deliver+0x133/0x210 [ 53.266247][ T7208] ip_rcv_finish+0x121/0x160 [ 53.270822][ T7208] ip_rcv+0x18f/0x1a0 [ 53.274791][ T7208] __netif_receive_skb_one_core+0xa7/0xe0 [ 53.280508][ T7208] __netif_receive_skb+0x37/0xf0 [ 53.285428][ T7208] netif_receive_skb_internal+0x59/0x190 [ 53.291041][ T7208] napi_gro_receive+0x28f/0x330 [ 53.295878][ T7208] receive_buf+0x284/0x30b0 [ 53.300368][ T7208] virtnet_poll+0x436/0x7d0 [ 53.304856][ T7208] net_rx_action+0x3ae/0xa50 [ 53.309421][ T7208] [ 53.311731][ T7208] write to 0xffff88811e968a0c of 4 bytes by task 7208 on cpu 1: [ 53.319342][ T7208] tcp_rcv_space_adjust+0x40f/0x4c0 [ 53.324538][ T7208] tcp_recvmsg+0xdaa/0x1a30 [ 53.329031][ T7208] inet_recvmsg+0xbb/0x250 [ 53.333428][ T7208] sock_recvmsg+0x92/0xb0 [ 53.337734][ T7208] sock_read_iter+0x15f/0x1e0 [ 53.342390][ T7208] new_sync_read+0x389/0x4f0 [ 53.346964][ T7208] __vfs_read+0xb1/0xc0 [ 53.351099][ T7208] vfs_read+0x143/0x2c0 [ 53.355236][ T7208] ksys_read+0xd5/0x1b0 [ 53.359374][ T7208] __x64_sys_read+0x4c/0x60 [ 53.363861][ T7208] do_syscall_64+0xcf/0x2f0 [ 53.368348][ T7208] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 53.374211][ T7208] [ 53.376516][ T7208] Reported by Kernel Concurrency Sanitizer on: [ 53.383517][ T7208] CPU: 1 PID: 7208 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 53.390603][ T7208] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.400637][ T7208] ================================================================== [ 53.408678][ T7208] Kernel panic - not syncing: panic_on_warn set ... [ 53.415246][ T7208] CPU: 1 PID: 7208 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 53.422328][ T7208] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 53.433501][ T7208] Call Trace: [ 53.436778][ T7208] dump_stack+0xf5/0x159 [ 53.441001][ T7208] panic+0x209/0x639 [ 53.444892][ T7208] ? ksys_read+0xd5/0x1b0 [ 53.449204][ T7208] ? vprintk_func+0x8d/0x140 [ 53.453777][ T7208] kcsan_report.cold+0xc/0x1b [ 53.458436][ T7208] __kcsan_setup_watchpoint+0x3ee/0x510 [ 53.463964][ T7208] __tsan_write4+0x32/0x40 [ 53.468368][ T7208] tcp_rcv_space_adjust+0x40f/0x4c0 [ 53.474400][ T7208] tcp_recvmsg+0xdaa/0x1a30 [ 53.478897][ T7208] ? __kcsan_setup_watchpoint+0x96/0x510 [ 53.484518][ T7208] inet_recvmsg+0xbb/0x250 [ 53.488928][ T7208] ? __tsan_read8+0x2c/0x30 [ 53.493416][ T7208] ? inet_sendpage+0x100/0x100 [ 53.498161][ T7208] sock_recvmsg+0x92/0xb0 [ 53.502475][ T7208] sock_read_iter+0x15f/0x1e0 [ 53.507142][ T7208] new_sync_read+0x389/0x4f0 [ 53.511722][ T7208] __vfs_read+0xb1/0xc0 [ 53.515913][ T7208] vfs_read+0x143/0x2c0 [ 53.520052][ T7208] ksys_read+0xd5/0x1b0 [ 53.524200][ T7208] __x64_sys_read+0x4c/0x60 [ 53.528690][ T7208] do_syscall_64+0xcf/0x2f0 [ 53.533182][ T7208] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 53.539050][ T7208] RIP: 0033:0x47c530 [ 53.542934][ T7208] 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 [ 53.562520][ T7208] RSP: 002b:000000c4202f77d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 53.570915][ T7208] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 53.578958][ T7208] RDX: 0000000000001000 RSI: 000000c42015e000 RDI: 0000000000000003 [ 53.586912][ T7208] RBP: 000000c4202f7830 R08: 0000000000000000 R09: 0000000000000000 [ 53.594889][ T7208] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000100 [ 53.602848][ T7208] R13: ffffffffffffffff R14: 0000000000000008 R15: ffffffffffffffff [ 53.612165][ T7208] Kernel Offset: disabled [ 53.616490][ T7208] Rebooting in 86400 seconds..