[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.673718][ T25] audit: type=1800 audit(1571662389.185:25): pid=7053 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.693437][ T25] audit: type=1800 audit(1571662389.185:26): pid=7053 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.715221][ T25] audit: type=1800 audit(1571662389.185:27): pid=7053 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 '10.128.10.63' (ECDSA) to the list of known hosts. 2019/10/21 12:53:17 fuzzer started 2019/10/21 12:53:19 dialing manager at 10.128.0.105:39747 2019/10/21 12:53:19 syscalls: 2524 2019/10/21 12:53:19 code coverage: enabled 2019/10/21 12:53:19 comparison tracing: enabled 2019/10/21 12:53:19 extra coverage: extra coverage is not supported by the kernel 2019/10/21 12:53:19 setuid sandbox: enabled 2019/10/21 12:53:19 namespace sandbox: enabled 2019/10/21 12:53:19 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/21 12:53:19 fault injection: enabled 2019/10/21 12:53:19 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/21 12:53:19 net packet injection: enabled 2019/10/21 12:53:19 net device setup: enabled 2019/10/21 12:53:19 concurrency sanitizer: enabled syzkaller login: [ 45.849361][ T7207] ================================================================== [ 45.857505][ T7207] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 45.864036][ T7207] [ 45.866362][ T7207] write to 0xffff888126a365fc of 4 bytes by task 7206 on cpu 0: [ 45.873980][ T7207] tcp_recvmsg+0xd86/0x1a30 [ 45.878460][ T7207] inet_recvmsg+0xbb/0x250 [ 45.882869][ T7207] sock_recvmsg+0x92/0xb0 [ 45.887190][ T7207] sock_read_iter+0x15f/0x1e0 [ 45.891879][ T7207] new_sync_read+0x389/0x4f0 [ 45.896455][ T7207] __vfs_read+0xb1/0xc0 [ 45.900588][ T7207] vfs_read+0x143/0x2c0 [ 45.904894][ T7207] ksys_read+0xd5/0x1b0 [ 45.909027][ T7207] __x64_sys_read+0x4c/0x60 [ 45.913512][ T7207] do_syscall_64+0xcc/0x370 [ 45.918002][ T7207] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.923959][ T7207] [ 45.926267][ T7207] read to 0xffff888126a365fc of 4 bytes by task 7207 on cpu 1: [ 45.933783][ T7207] tcp_poll+0x1cc/0x6b0 [ 45.938001][ T7207] sock_poll+0xed/0x250 [ 45.942164][ T7207] ep_item_poll.isra.0+0x90/0x190 [ 45.947171][ T7207] ep_send_events_proc+0x113/0x590 [ 45.952266][ T7207] ep_scan_ready_list.constprop.0+0x189/0x500 [ 45.958316][ T7207] ep_poll+0xe3/0x900 [ 45.962284][ T7207] do_epoll_wait+0x162/0x180 [ 45.966861][ T7207] __x64_sys_epoll_pwait+0xcd/0x180 [ 45.972163][ T7207] do_syscall_64+0xcc/0x370 [ 45.976670][ T7207] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 45.982536][ T7207] [ 45.984840][ T7207] Reported by Kernel Concurrency Sanitizer on: [ 45.991498][ T7207] CPU: 1 PID: 7207 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 45.999445][ T7207] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.009569][ T7207] ================================================================== [ 46.017611][ T7207] Kernel panic - not syncing: panic_on_warn set ... [ 46.024184][ T7207] CPU: 1 PID: 7207 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 46.031616][ T7207] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 46.041730][ T7207] Call Trace: [ 46.045008][ T7207] dump_stack+0xf5/0x159 [ 46.049242][ T7207] panic+0x210/0x640 [ 46.053126][ T7207] ? do_syscall_64+0xcc/0x370 [ 46.057798][ T7207] ? vprintk_func+0x8d/0x140 [ 46.062376][ T7207] kcsan_report.cold+0xc/0x10 [ 46.067031][ T7207] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 46.072553][ T7207] __tsan_read4+0x2c/0x30 [ 46.076860][ T7207] tcp_poll+0x1cc/0x6b0 [ 46.081007][ T7207] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 46.086445][ T7207] sock_poll+0xed/0x250 [ 46.090580][ T7207] ? sock_read_iter+0x1e0/0x1e0 [ 46.095419][ T7207] ep_item_poll.isra.0+0x90/0x190 [ 46.100419][ T7207] ep_send_events_proc+0x113/0x590 [ 46.105503][ T7207] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 46.111128][ T7207] ep_scan_ready_list.constprop.0+0x189/0x500 [ 46.117189][ T7207] ? ep_loop_check_proc+0x2f0/0x2f0 [ 46.122366][ T7207] ep_poll+0xe3/0x900 [ 46.126410][ T7207] ? __fget+0xb8/0x1d0 [ 46.130465][ T7207] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 46.136274][ T7207] ? __fget_light+0xaf/0x190 [ 46.140840][ T7207] do_epoll_wait+0x162/0x180 [ 46.145757][ T7207] __x64_sys_epoll_pwait+0xcd/0x180 [ 46.150935][ T7207] do_syscall_64+0xcc/0x370 [ 46.155417][ T7207] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.161283][ T7207] RIP: 0033:0x45b300 [ 46.165158][ T7207] Code: 0f 05 89 44 24 20 c3 cc cc cc 8b 7c 24 08 48 8b 74 24 10 8b 54 24 18 44 8b 54 24 1c 49 c7 c0 00 00 00 00 b8 19 01 00 00 0f 05 <89> 44 24 20 c3 cc cc cc cc cc cc cc cc cc cc cc 8b 7c 24 08 48 c7 [ 46.184738][ T7207] RSP: 002b:000000c42004f8d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 46.193150][ T7207] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b300 [ 46.201811][ T7207] RDX: 0000000000000080 RSI: 000000c42004f918 RDI: 0000000000000004 [ 46.209771][ T7207] RBP: 000000c42004ff18 R08: 0000000000000000 R09: 00000000000020de [ 46.217722][ T7207] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000042f0a0 [ 46.225966][ T7207] R13: 00000000000000f1 R14: 0000000000000011 R15: 0000000000000000 [ 46.235707][ T7207] Kernel Offset: disabled [ 46.240035][ T7207] Rebooting in 86400 seconds..