[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.988397][ T25] audit: type=1800 audit(1571376146.052:25): pid=6997 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.015524][ T25] audit: type=1800 audit(1571376146.052:26): pid=6997 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.035668][ T25] audit: type=1800 audit(1571376146.052:27): pid=6997 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 '10.128.0.233' (ECDSA) to the list of known hosts. 2019/10/18 05:22:37 fuzzer started 2019/10/18 05:22:39 dialing manager at 10.128.0.105:43535 2019/10/18 05:22:39 syscalls: 2524 2019/10/18 05:22:39 code coverage: enabled 2019/10/18 05:22:39 comparison tracing: enabled 2019/10/18 05:22:39 extra coverage: extra coverage is not supported by the kernel 2019/10/18 05:22:39 setuid sandbox: enabled 2019/10/18 05:22:39 namespace sandbox: enabled 2019/10/18 05:22:39 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/18 05:22:39 fault injection: enabled 2019/10/18 05:22:39 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/18 05:22:39 net packet injection: enabled 2019/10/18 05:22:39 net device setup: enabled 2019/10/18 05:22:39 concurrency sanitizer: enabled syzkaller login: [ 49.879171][ T7168] ================================================================== [ 49.887305][ T7168] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 49.893691][ T7168] [ 49.896049][ T7168] read to 0xffff888122f5f7bc of 4 bytes by task 7159 on cpu 0: [ 49.903614][ T7168] tcp_poll+0x1cc/0x6b0 [ 49.907752][ T7168] sock_poll+0xed/0x250 [ 49.912867][ T7168] ep_item_poll.isra.0+0x90/0x190 [ 49.918388][ T7168] ep_send_events_proc+0x113/0x590 [ 49.923477][ T7168] ep_scan_ready_list.constprop.0+0x189/0x500 [ 49.929537][ T7168] ep_poll+0xe3/0x900 [ 49.933495][ T7168] do_epoll_wait+0x162/0x180 [ 49.938097][ T7168] __x64_sys_epoll_pwait+0xcd/0x180 [ 49.943277][ T7168] do_syscall_64+0xcc/0x370 [ 49.947758][ T7168] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.953619][ T7168] [ 49.955941][ T7168] write to 0xffff888122f5f7bc of 4 bytes by task 7168 on cpu 1: [ 49.963547][ T7168] tcp_recvmsg+0xd86/0x1a30 [ 49.968044][ T7168] inet_recvmsg+0xbb/0x250 [ 49.972465][ T7168] sock_recvmsg+0x92/0xb0 [ 49.976786][ T7168] sock_read_iter+0x15f/0x1e0 [ 49.982220][ T7168] new_sync_read+0x389/0x4f0 [ 49.986785][ T7168] __vfs_read+0xb1/0xc0 [ 49.991098][ T7168] vfs_read+0x143/0x2c0 [ 49.995228][ T7168] ksys_read+0xd5/0x1b0 [ 49.999380][ T7168] __x64_sys_read+0x4c/0x60 [ 50.003871][ T7168] do_syscall_64+0xcc/0x370 [ 50.008352][ T7168] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.014212][ T7168] [ 50.016517][ T7168] Reported by Kernel Concurrency Sanitizer on: [ 50.022742][ T7168] CPU: 1 PID: 7168 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.030170][ T7168] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.040229][ T7168] ================================================================== [ 50.048276][ T7168] Kernel panic - not syncing: panic_on_warn set ... [ 50.054847][ T7168] CPU: 1 PID: 7168 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 50.062399][ T7168] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.072443][ T7168] Call Trace: [ 50.075730][ T7168] dump_stack+0xf5/0x159 [ 50.079967][ T7168] panic+0x210/0x640 [ 50.083855][ T7168] ? __x64_sys_read+0x4c/0x60 [ 50.088510][ T7168] ? vprintk_func+0x8d/0x140 [ 50.093078][ T7168] kcsan_report.cold+0xc/0x10 [ 50.097734][ T7168] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 50.103695][ T7168] __tsan_write4+0x32/0x40 [ 50.108088][ T7168] tcp_recvmsg+0xd86/0x1a30 [ 50.112576][ T7168] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 50.118202][ T7168] inet_recvmsg+0xbb/0x250 [ 50.122609][ T7168] ? __tsan_read8+0x2c/0x30 [ 50.127090][ T7168] ? inet_sendpage+0x100/0x100 [ 50.131831][ T7168] sock_recvmsg+0x92/0xb0 [ 50.136139][ T7168] sock_read_iter+0x15f/0x1e0 [ 50.140798][ T7168] new_sync_read+0x389/0x4f0 [ 50.145380][ T7168] __vfs_read+0xb1/0xc0 [ 50.149513][ T7168] vfs_read+0x143/0x2c0 [ 50.153647][ T7168] ksys_read+0xd5/0x1b0 [ 50.157784][ T7168] __x64_sys_read+0x4c/0x60 [ 50.162269][ T7168] do_syscall_64+0xcc/0x370 [ 50.166815][ T7168] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.172728][ T7168] RIP: 0033:0x47c530 [ 50.176629][ T7168] 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 [ 50.196298][ T7168] RSP: 002b:000000c4203a3810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 50.204686][ T7168] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.212690][ T7168] RDX: 0000000000001000 RSI: 000000c420056000 RDI: 0000000000000003 [ 50.220687][ T7168] RBP: 000000c4203a3868 R08: 0000000000000000 R09: 0000000000000000 [ 50.228640][ T7168] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000040 [ 50.236634][ T7168] R13: ffffffffffffffff R14: 0000000000000020 R15: ffffffffffffffff [ 50.245977][ T7168] Kernel Offset: disabled [ 50.250357][ T7168] Rebooting in 86400 seconds..