[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.259838][ T26] audit: type=1800 audit(1570561766.927:25): pid=7170 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.298289][ T26] audit: type=1800 audit(1570561766.927:26): pid=7170 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.342860][ T26] audit: type=1800 audit(1570561766.937:27): pid=7170 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 '10.128.10.5' (ECDSA) to the list of known hosts. 2019/10/08 19:09:38 fuzzer started 2019/10/08 19:09:40 dialing manager at 10.128.0.105:35069 2019/10/08 19:09:40 syscalls: 2523 2019/10/08 19:09:40 code coverage: enabled 2019/10/08 19:09:40 comparison tracing: enabled 2019/10/08 19:09:40 extra coverage: extra coverage is not supported by the kernel 2019/10/08 19:09:40 setuid sandbox: enabled 2019/10/08 19:09:40 namespace sandbox: enabled 2019/10/08 19:09:40 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/08 19:09:40 fault injection: enabled 2019/10/08 19:09:40 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/08 19:09:40 net packet injection: enabled 2019/10/08 19:09:40 net device setup: enabled 2019/10/08 19:09:40 concurrency sanitizer: enabled syzkaller login: [ 48.519187][ T7321] ================================================================== [ 48.527994][ T7321] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 48.535785][ T7321] [ 48.538330][ T7321] read to 0xffff88812931f30c of 4 bytes by interrupt on cpu 0: [ 48.546372][ T7321] tcp_add_backlog+0x43/0xcc0 [ 48.551133][ T7321] tcp_v4_rcv+0x1aba/0x1bf0 [ 48.555627][ T7321] ip_protocol_deliver_rcu+0x51/0x470 [ 48.561321][ T7321] ip_local_deliver_finish+0x110/0x140 [ 48.566995][ T7321] ip_local_deliver+0x133/0x210 [ 48.571837][ T7321] ip_rcv_finish+0x121/0x160 [ 48.576645][ T7321] ip_rcv+0x18f/0x1a0 [ 48.580806][ T7321] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.586703][ T7321] __netif_receive_skb+0x37/0xf0 [ 48.591677][ T7321] netif_receive_skb_internal+0x59/0x190 [ 48.597309][ T7321] napi_gro_receive+0x28f/0x330 [ 48.602513][ T7321] receive_buf+0x284/0x30b0 [ 48.607339][ T7321] virtnet_poll+0x436/0x7d0 [ 48.612162][ T7321] net_rx_action+0x3ae/0xa50 [ 48.616829][ T7321] [ 48.619182][ T7321] write to 0xffff88812931f30c of 4 bytes by task 7321 on cpu 1: [ 48.627222][ T7321] tcp_rcv_space_adjust+0x40f/0x4c0 [ 48.632414][ T7321] tcp_recvmsg+0xdaa/0x1a30 [ 48.636922][ T7321] inet_recvmsg+0xbb/0x250 [ 48.641576][ T7321] sock_recvmsg+0x92/0xb0 [ 48.645992][ T7321] sock_read_iter+0x15f/0x1e0 [ 48.652831][ T7321] new_sync_read+0x389/0x4f0 [ 48.657733][ T7321] __vfs_read+0xb1/0xc0 [ 48.661937][ T7321] vfs_read+0x143/0x2c0 [ 48.666201][ T7321] ksys_read+0xd5/0x1b0 [ 48.671084][ T7321] __x64_sys_read+0x4c/0x60 [ 48.677049][ T7321] do_syscall_64+0xcf/0x2f0 [ 48.681744][ T7321] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.688013][ T7321] [ 48.690525][ T7321] Reported by Kernel Concurrency Sanitizer on: [ 48.697657][ T7321] CPU: 1 PID: 7321 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.705499][ T7321] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.716520][ T7321] ================================================================== [ 48.725619][ T7321] Kernel panic - not syncing: panic_on_warn set ... [ 48.733759][ T7321] CPU: 1 PID: 7321 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 48.741894][ T7321] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.752928][ T7321] Call Trace: [ 48.756966][ T7321] dump_stack+0xf5/0x159 [ 48.761327][ T7321] panic+0x209/0x639 [ 48.765765][ T7321] ? ksys_read+0xd5/0x1b0 [ 48.770660][ T7321] ? vprintk_func+0x8d/0x140 [ 48.775725][ T7321] kcsan_report.cold+0xc/0x1b [ 48.780740][ T7321] __kcsan_setup_watchpoint+0x3ee/0x510 [ 48.786586][ T7321] __tsan_write4+0x32/0x40 [ 48.791713][ T7321] tcp_rcv_space_adjust+0x40f/0x4c0 [ 48.797143][ T7321] tcp_recvmsg+0xdaa/0x1a30 [ 48.801773][ T7321] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.807656][ T7321] inet_recvmsg+0xbb/0x250 [ 48.812212][ T7321] ? __tsan_read8+0x2c/0x30 [ 48.816806][ T7321] ? inet_sendpage+0x100/0x100 [ 48.821918][ T7321] sock_recvmsg+0x92/0xb0 [ 48.826363][ T7321] sock_read_iter+0x15f/0x1e0 [ 48.831159][ T7321] new_sync_read+0x389/0x4f0 [ 48.835846][ T7321] __vfs_read+0xb1/0xc0 [ 48.840395][ T7321] vfs_read+0x143/0x2c0 [ 48.844812][ T7321] ksys_read+0xd5/0x1b0 [ 48.848971][ T7321] __x64_sys_read+0x4c/0x60 [ 48.853678][ T7321] do_syscall_64+0xcf/0x2f0 [ 48.858327][ T7321] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.864371][ T7321] RIP: 0033:0x47c530 [ 48.868464][ T7321] 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 [ 48.889590][ T7321] RSP: 002b:000000c4203a17d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 48.898140][ T7321] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.907302][ T7321] RDX: 0000000000001000 RSI: 000000c420306000 RDI: 0000000000000003 [ 48.916107][ T7321] RBP: 000000c4203a1830 R08: 0000000000000000 R09: 0000000000000000 [ 48.924371][ T7321] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000004 [ 48.933591][ T7321] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 48.943782][ T7321] Kernel Offset: disabled [ 48.948240][ T7321] Rebooting in 86400 seconds..