[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 40.210263][ T25] audit: type=1800 audit(1571197801.625:25): pid=7058 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 40.232080][ T25] audit: type=1800 audit(1571197801.635:26): pid=7058 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 40.254056][ T25] audit: type=1800 audit(1571197801.635:27): pid=7058 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 '10.128.10.34' (ECDSA) to the list of known hosts. 2019/10/16 03:50:08 fuzzer started 2019/10/16 03:50:09 dialing manager at 10.128.0.105:34737 2019/10/16 03:50:09 syscalls: 2524 2019/10/16 03:50:09 code coverage: enabled 2019/10/16 03:50:09 comparison tracing: enabled 2019/10/16 03:50:09 extra coverage: extra coverage is not supported by the kernel 2019/10/16 03:50:09 setuid sandbox: enabled 2019/10/16 03:50:09 namespace sandbox: enabled 2019/10/16 03:50:09 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/16 03:50:09 fault injection: enabled 2019/10/16 03:50:09 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/16 03:50:09 net packet injection: enabled 2019/10/16 03:50:09 net device setup: enabled 2019/10/16 03:50:09 concurrency sanitizer: enabled syzkaller login: [ 48.344333][ T7214] ================================================================== [ 48.352490][ T7214] BUG: KCSAN: data-race in tcp_add_backlog / tcp_rcv_space_adjust [ 48.360559][ T7214] [ 48.362896][ T7214] read to 0xffff88811f55ca4c of 4 bytes by interrupt on cpu 1: [ 48.370424][ T7214] tcp_add_backlog+0x43/0xcc0 [ 48.375097][ T7214] tcp_v4_rcv+0x1a60/0x1bb0 [ 48.379596][ T7214] ip_protocol_deliver_rcu+0x4d/0x420 [ 48.385279][ T7214] ip_local_deliver_finish+0x110/0x140 [ 48.390725][ T7214] ip_local_deliver+0x133/0x210 [ 48.395571][ T7214] ip_rcv_finish+0x121/0x160 [ 48.400311][ T7214] ip_rcv+0x18f/0x1a0 [ 48.404453][ T7214] __netif_receive_skb_one_core+0xa7/0xe0 [ 48.410157][ T7214] __netif_receive_skb+0x37/0xf0 [ 48.415228][ T7214] netif_receive_skb_internal+0x59/0x190 [ 48.420860][ T7214] napi_gro_receive+0x28f/0x330 [ 48.425784][ T7214] receive_buf+0x284/0x30b0 [ 48.430268][ T7214] virtnet_poll+0x436/0x7d0 [ 48.434769][ T7214] net_rx_action+0x3ae/0xa90 [ 48.439342][ T7214] [ 48.441717][ T7214] write to 0xffff88811f55ca4c of 4 bytes by task 7214 on cpu 0: [ 48.449338][ T7214] tcp_rcv_space_adjust+0x40f/0x4c0 [ 48.454845][ T7214] tcp_recvmsg+0xdaa/0x1a30 [ 48.459480][ T7214] inet_recvmsg+0xbb/0x250 [ 48.463904][ T7214] sock_recvmsg+0x92/0xb0 [ 48.468219][ T7214] sock_read_iter+0x15f/0x1e0 [ 48.472888][ T7214] new_sync_read+0x389/0x4f0 [ 48.477485][ T7214] __vfs_read+0xb1/0xc0 [ 48.481622][ T7214] vfs_read+0x143/0x2c0 [ 48.485774][ T7214] ksys_read+0xd5/0x1b0 [ 48.489927][ T7214] __x64_sys_read+0x4c/0x60 [ 48.494423][ T7214] do_syscall_64+0xcc/0x370 [ 48.498907][ T7214] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.504771][ T7214] [ 48.507079][ T7214] Reported by Kernel Concurrency Sanitizer on: [ 48.513302][ T7214] CPU: 0 PID: 7214 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.520732][ T7214] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.530778][ T7214] ================================================================== [ 48.538832][ T7214] Kernel panic - not syncing: panic_on_warn set ... [ 48.545408][ T7214] CPU: 0 PID: 7214 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.553026][ T7214] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.563579][ T7214] Call Trace: [ 48.566860][ T7214] dump_stack+0xf5/0x159 [ 48.571100][ T7214] panic+0x210/0x640 [ 48.575014][ T7214] ? ksys_read+0xd5/0x1b0 [ 48.579399][ T7214] ? vprintk_func+0x8d/0x140 [ 48.583994][ T7214] kcsan_report.cold+0xc/0x1b [ 48.590670][ T7214] __kcsan_setup_watchpoint+0x3ee/0x510 [ 48.596483][ T7214] __tsan_write4+0x32/0x40 [ 48.600885][ T7214] tcp_rcv_space_adjust+0x40f/0x4c0 [ 48.606157][ T7214] tcp_recvmsg+0xdaa/0x1a30 [ 48.610812][ T7214] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.616656][ T7214] inet_recvmsg+0xbb/0x250 [ 48.621269][ T7214] ? __tsan_read8+0x2c/0x30 [ 48.625763][ T7214] ? inet_sendpage+0x100/0x100 [ 48.630522][ T7214] sock_recvmsg+0x92/0xb0 [ 48.634835][ T7214] sock_read_iter+0x15f/0x1e0 [ 48.639523][ T7214] new_sync_read+0x389/0x4f0 [ 48.644138][ T7214] __vfs_read+0xb1/0xc0 [ 48.648288][ T7214] vfs_read+0x143/0x2c0 [ 48.652533][ T7214] ksys_read+0xd5/0x1b0 [ 48.656681][ T7214] __x64_sys_read+0x4c/0x60 [ 48.662249][ T7214] do_syscall_64+0xcc/0x370 [ 48.666890][ T7214] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.672771][ T7214] RIP: 0033:0x47c530 [ 48.676669][ T7214] 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 [ 48.696351][ T7214] RSP: 002b:000000c420307810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 48.704755][ T7214] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.712742][ T7214] RDX: 0000000000001000 RSI: 000000c420376000 RDI: 0000000000000003 [ 48.720708][ T7214] RBP: 000000c420307868 R08: 0000000000000000 R09: 0000000000000000 [ 48.728677][ T7214] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000002 [ 48.736630][ T7214] R13: ffffffffffffffff R14: 0000000000000004 R15: ffffffffffffffff [ 48.746058][ T7214] Kernel Offset: disabled [ 48.750422][ T7214] Rebooting in 86400 seconds..