[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.751180][ T25] audit: type=1800 audit(1571773610.003:25): pid=6991 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.785607][ T25] audit: type=1800 audit(1571773610.003:26): pid=6991 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.809055][ T25] audit: type=1800 audit(1571773610.003:27): pid=6991 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 '10.128.0.117' (ECDSA) to the list of known hosts. 2019/10/22 19:46:56 fuzzer started 2019/10/22 19:46:57 dialing manager at 10.128.0.105:33369 2019/10/22 19:46:57 syscalls: 2524 2019/10/22 19:46:57 code coverage: enabled 2019/10/22 19:46:57 comparison tracing: enabled 2019/10/22 19:46:57 extra coverage: extra coverage is not supported by the kernel 2019/10/22 19:46:57 setuid sandbox: enabled 2019/10/22 19:46:57 namespace sandbox: enabled 2019/10/22 19:46:57 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 19:46:57 fault injection: enabled 2019/10/22 19:46:57 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 19:46:57 net packet injection: enabled 2019/10/22 19:46:57 net device setup: enabled 2019/10/22 19:46:57 concurrency sanitizer: enabled syzkaller login: [ 44.253566][ T7148] ================================================================== [ 44.261698][ T7148] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 44.269504][ T7148] [ 44.271810][ T7148] read to 0xffff88812243b34c of 4 bytes by interrupt on cpu 0: [ 44.279587][ T7148] tcp_add_backlog+0x43/0xcc0 [ 44.284239][ T7148] tcp_v4_rcv+0x1a60/0x1bb0 [ 44.288714][ T7148] ip_protocol_deliver_rcu+0x4d/0x420 [ 44.294078][ T7148] ip_local_deliver_finish+0x110/0x140 [ 44.299509][ T7148] ip_local_deliver+0x133/0x210 [ 44.304353][ T7148] ip_rcv_finish+0x121/0x160 [ 44.308913][ T7148] ip_rcv+0x18f/0x1a0 [ 44.312877][ T7148] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.318582][ T7148] __netif_receive_skb+0x37/0xf0 [ 44.323507][ T7148] netif_receive_skb_internal+0x59/0x190 [ 44.329212][ T7148] napi_gro_receive+0x28f/0x330 [ 44.334047][ T7148] receive_buf+0x284/0x30b0 [ 44.338529][ T7148] virtnet_poll+0x436/0x7d0 [ 44.343006][ T7148] net_rx_action+0x3ae/0xa90 [ 44.347571][ T7148] [ 44.349893][ T7148] write to 0xffff88812243b34c of 4 bytes by task 7148 on cpu 1: [ 44.357585][ T7148] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.362757][ T7148] tcp_recvmsg+0xdaa/0x1a30 [ 44.367233][ T7148] inet_recvmsg+0xbb/0x250 [ 44.371625][ T7148] sock_recvmsg+0x92/0xb0 [ 44.375927][ T7148] sock_read_iter+0x15f/0x1e0 [ 44.380580][ T7148] new_sync_read+0x389/0x4f0 [ 44.385143][ T7148] __vfs_read+0xb1/0xc0 [ 44.389270][ T7148] vfs_read+0x143/0x2c0 [ 44.393400][ T7148] ksys_read+0xd5/0x1b0 [ 44.397530][ T7148] __x64_sys_read+0x4c/0x60 [ 44.402009][ T7148] do_syscall_64+0xcc/0x370 [ 44.406487][ T7148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.412360][ T7148] [ 44.414664][ T7148] Reported by Kernel Concurrency Sanitizer on: [ 44.420793][ T7148] CPU: 1 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.428216][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.438252][ T7148] ================================================================== [ 44.446285][ T7148] Kernel panic - not syncing: panic_on_warn set ... [ 44.452847][ T7148] CPU: 1 PID: 7148 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.460284][ T7148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.470314][ T7148] Call Trace: [ 44.473582][ T7148] dump_stack+0xf5/0x159 [ 44.477799][ T7148] panic+0x210/0x640 [ 44.481674][ T7148] ? ksys_read+0xd5/0x1b0 [ 44.485989][ T7148] ? vprintk_func+0x8d/0x140 [ 44.490676][ T7148] kcsan_report.cold+0xc/0x10 [ 44.495341][ T7148] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 44.500867][ T7148] __tsan_write4+0x32/0x40 [ 44.505274][ T7148] tcp_rcv_space_adjust+0x40f/0x4c0 [ 44.510461][ T7148] tcp_recvmsg+0xdaa/0x1a30 [ 44.514952][ T7148] ? debug_smp_processor_id+0x4c/0x172 [ 44.520401][ T7148] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 44.526024][ T7148] inet_recvmsg+0xbb/0x250 [ 44.530425][ T7148] ? __tsan_read8+0x2c/0x30 [ 44.534913][ T7148] ? inet_sendpage+0x100/0x100 [ 44.539656][ T7148] sock_recvmsg+0x92/0xb0 [ 44.543966][ T7148] sock_read_iter+0x15f/0x1e0 [ 44.548622][ T7148] new_sync_read+0x389/0x4f0 [ 44.553193][ T7148] __vfs_read+0xb1/0xc0 [ 44.557325][ T7148] vfs_read+0x143/0x2c0 [ 44.561469][ T7148] ksys_read+0xd5/0x1b0 [ 44.565604][ T7148] __x64_sys_read+0x4c/0x60 [ 44.570615][ T7148] do_syscall_64+0xcc/0x370 [ 44.575101][ T7148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.580969][ T7148] RIP: 0033:0x47c530 [ 44.584855][ T7148] 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 [ 44.604430][ T7148] RSP: 002b:000000c4204f77d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 44.612817][ T7148] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.620778][ T7148] RDX: 0000000000001000 RSI: 000000c4203d8000 RDI: 0000000000000003 [ 44.628732][ T7148] RBP: 000000c4204f7830 R08: 0000000000000000 R09: 0000000000000000 [ 44.636679][ T7148] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 44.644644][ T7148] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 44.653886][ T7148] Kernel Offset: disabled [ 44.658202][ T7148] Rebooting in 86400 seconds..