[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.665561][ T26] audit: type=1800 audit(1570514489.626:25): pid=7101 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.708277][ T26] audit: type=1800 audit(1570514489.626:26): pid=7101 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.743536][ T26] audit: type=1800 audit(1570514489.636:27): pid=7101 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 '10.128.0.83' (ECDSA) to the list of known hosts. 2019/10/08 06:01:36 fuzzer started 2019/10/08 06:01:37 dialing manager at 10.128.0.105:39369 2019/10/08 06:01:37 syscalls: 2523 2019/10/08 06:01:37 code coverage: enabled 2019/10/08 06:01:37 comparison tracing: enabled 2019/10/08 06:01:37 extra coverage: extra coverage is not supported by the kernel 2019/10/08 06:01:37 setuid sandbox: enabled 2019/10/08 06:01:37 namespace sandbox: enabled 2019/10/08 06:01:37 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/08 06:01:37 fault injection: enabled 2019/10/08 06:01:37 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/08 06:01:37 net packet injection: enabled 2019/10/08 06:01:37 net device setup: enabled 2019/10/08 06:01:37 concurrency sanitizer: enabled syzkaller login: [ 44.029056][ T7255] ================================================================== [ 44.037226][ T7255] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 44.045226][ T7255] [ 44.047534][ T7255] read to 0xffff88812604214c of 4 bytes by interrupt on cpu 1: [ 44.055057][ T7255] tcp_add_backlog+0x43/0xcc0 [ 44.059720][ T7255] tcp_v4_rcv+0x1aba/0x1bf0 [ 44.064219][ T7255] ip_protocol_deliver_rcu+0x51/0x470 [ 44.069580][ T7255] ip_local_deliver_finish+0x110/0x140 [ 44.075175][ T7255] ip_local_deliver+0x133/0x210 [ 44.080005][ T7255] ip_rcv_finish+0x121/0x160 [ 44.084573][ T7255] ip_rcv+0x18f/0x1a0 [ 44.088538][ T7255] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.094234][ T7255] __netif_receive_skb+0x37/0xf0 [ 44.099166][ T7255] netif_receive_skb_internal+0x59/0x190 [ 44.104771][ T7255] napi_gro_receive+0x28f/0x330 [ 44.109600][ T7255] receive_buf+0x284/0x30b0 [ 44.114092][ T7255] virtnet_poll+0x436/0x7d0 [ 44.118570][ T7255] net_rx_action+0x3ae/0xa50 [ 44.123136][ T7255] [ 44.125460][ T7255] write to 0xffff88812604214c of 4 bytes by task 7255 on cpu 0: [ 44.133223][ T7255] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.138408][ T7255] tcp_recvmsg+0xdaa/0x1a30 [ 44.142894][ T7255] inet_recvmsg+0xbb/0x250 [ 44.147286][ T7255] sock_recvmsg+0x92/0xb0 [ 44.151589][ T7255] sock_read_iter+0x15f/0x1e0 [ 44.156244][ T7255] new_sync_read+0x389/0x4f0 [ 44.160808][ T7255] __vfs_read+0xb1/0xc0 [ 44.164939][ T7255] vfs_read+0x143/0x2c0 [ 44.169068][ T7255] ksys_read+0xd5/0x1b0 [ 44.173211][ T7255] __x64_sys_read+0x4c/0x60 [ 44.177716][ T7255] do_syscall_64+0xcf/0x2f0 [ 44.182214][ T7255] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.188280][ T7255] [ 44.190584][ T7255] Reported by Kernel Concurrency Sanitizer on: [ 44.196716][ T7255] CPU: 0 PID: 7255 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 44.203919][ T7255] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.214060][ T7255] ================================================================== [ 44.222112][ T7255] Kernel panic - not syncing: panic_on_warn set ... [ 44.228689][ T7255] CPU: 0 PID: 7255 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 44.235768][ T7255] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.245797][ T7255] Call Trace: [ 44.249066][ T7255] dump_stack+0xf5/0x159 [ 44.253287][ T7255] panic+0x209/0x639 [ 44.257180][ T7255] ? vprintk_func+0x8d/0x140 [ 44.261760][ T7255] kcsan_report.cold+0x57/0xeb [ 44.266503][ T7255] __kcsan_setup_watchpoint+0x342/0x500 [ 44.272036][ T7255] __tsan_write4+0x32/0x40 [ 44.276438][ T7255] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.281629][ T7255] tcp_recvmsg+0xdaa/0x1a30 [ 44.286124][ T7255] inet_recvmsg+0xbb/0x250 [ 44.290513][ T7255] ? __tsan_read8+0x2c/0x30 [ 44.294994][ T7255] ? inet_sendpage+0x100/0x100 [ 44.299753][ T7255] sock_recvmsg+0x92/0xb0 [ 44.304237][ T7255] sock_read_iter+0x15f/0x1e0 [ 44.308900][ T7255] new_sync_read+0x389/0x4f0 [ 44.313477][ T7255] __vfs_read+0xb1/0xc0 [ 44.317619][ T7255] vfs_read+0x143/0x2c0 [ 44.321755][ T7255] ksys_read+0xd5/0x1b0 [ 44.325899][ T7255] __x64_sys_read+0x4c/0x60 [ 44.330380][ T7255] do_syscall_64+0xcf/0x2f0 [ 44.334868][ T7255] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.340736][ T7255] RIP: 0033:0x47c530 [ 44.344611][ T7255] 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 [ 44.364209][ T7255] RSP: 002b:000000c4203bf7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 44.372725][ T7255] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.380908][ T7255] RDX: 0000000000001000 RSI: 000000c42031e000 RDI: 0000000000000003 [ 44.388947][ T7255] RBP: 000000c4203bf830 R08: 0000000000000000 R09: 0000000000000000 [ 44.396893][ T7255] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000010 [ 44.405920][ T7255] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 44.415152][ T7255] Kernel Offset: disabled [ 44.419473][ T7255] Rebooting in 86400 seconds..