[ 37.002156][ T23] audit: type=1800 audit(1571623103.813:25): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.030033][ T23] audit: type=1800 audit(1571623103.813:26): pid=7026 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.059235][ T23] audit: type=1800 audit(1571623103.813:27): pid=7026 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. [ 37.357756][ T7092] sshd (7092) used greatest stack depth: 10136 bytes left [....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[ ok 8[?25h[?0c. Debian GNU/Linux 7 syzkaller ttyS0 Warning: Permanently added '10.128.0.242' (ECDSA) to the list of known hosts. 2019/10/21 01:58:33 fuzzer started 2019/10/21 01:58:34 dialing manager at 10.128.0.105:43535 2019/10/21 01:58:34 syscalls: 2524 2019/10/21 01:58:34 code coverage: enabled 2019/10/21 01:58:34 comparison tracing: enabled 2019/10/21 01:58:34 extra coverage: extra coverage is not supported by the kernel 2019/10/21 01:58:34 setuid sandbox: enabled 2019/10/21 01:58:34 namespace sandbox: enabled 2019/10/21 01:58:34 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/21 01:58:34 fault injection: enabled 2019/10/21 01:58:34 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/21 01:58:34 net packet injection: enabled 2019/10/21 01:58:34 net device setup: enabled 2019/10/21 01:58:34 concurrency sanitizer: enabled syzkaller login: [ 48.184166][ T7181] ================================================================== [ 48.192312][ T7181] BUG: KCSAN: data-race in tcp_poll / tcp_recvmsg [ 48.198705][ T7181] [ 48.201029][ T7181] write to 0xffff8881255c977c of 4 bytes by task 7182 on cpu 0: [ 48.208731][ T7181] tcp_recvmsg+0xd86/0x1a30 [ 48.213224][ T7181] inet_recvmsg+0xbb/0x250 [ 48.217640][ T7181] sock_recvmsg+0x92/0xb0 [ 48.221974][ T7181] sock_read_iter+0x15f/0x1e0 [ 48.226661][ T7181] new_sync_read+0x389/0x4f0 [ 48.231236][ T7181] __vfs_read+0xb1/0xc0 [ 48.235380][ T7181] vfs_read+0x143/0x2c0 [ 48.239608][ T7181] ksys_read+0xd5/0x1b0 [ 48.243760][ T7181] __x64_sys_read+0x4c/0x60 [ 48.248253][ T7181] do_syscall_64+0xcc/0x370 [ 48.252755][ T7181] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.258640][ T7181] [ 48.260972][ T7181] read to 0xffff8881255c977c of 4 bytes by task 7181 on cpu 1: [ 48.268514][ T7181] tcp_poll+0x1cc/0x6b0 [ 48.272662][ T7181] sock_poll+0xed/0x250 [ 48.276812][ T7181] ep_item_poll.isra.0+0x90/0x190 [ 48.281824][ T7181] ep_send_events_proc+0x113/0x590 [ 48.286921][ T7181] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.292973][ T7181] ep_poll+0xe3/0x900 [ 48.297040][ T7181] do_epoll_wait+0x162/0x180 [ 48.301626][ T7181] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.306816][ T7181] do_syscall_64+0xcc/0x370 [ 48.311411][ T7181] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.317305][ T7181] [ 48.319795][ T7181] Reported by Kernel Concurrency Sanitizer on: [ 48.326004][ T7181] CPU: 1 PID: 7181 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.333554][ T7181] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.343598][ T7181] ================================================================== [ 48.351656][ T7181] Kernel panic - not syncing: panic_on_warn set ... [ 48.358234][ T7181] CPU: 1 PID: 7181 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.365680][ T7181] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.375738][ T7181] Call Trace: [ 48.379033][ T7181] dump_stack+0xf5/0x159 [ 48.383288][ T7181] panic+0x210/0x640 [ 48.387287][ T7181] ? do_syscall_64+0xcc/0x370 [ 48.391955][ T7181] ? vprintk_func+0x8d/0x140 [ 48.396541][ T7181] kcsan_report.cold+0xc/0x10 [ 48.401477][ T7181] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.407016][ T7181] __tsan_read4+0x2c/0x30 [ 48.411436][ T7181] tcp_poll+0x1cc/0x6b0 [ 48.415596][ T7181] ? tcp_alloc_md5sig_pool+0x320/0x320 [ 48.421056][ T7181] sock_poll+0xed/0x250 [ 48.426385][ T7181] ? sock_read_iter+0x1e0/0x1e0 [ 48.431228][ T7181] ep_item_poll.isra.0+0x90/0x190 [ 48.436417][ T7181] ep_send_events_proc+0x113/0x590 [ 48.441537][ T7181] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.447455][ T7181] ep_scan_ready_list.constprop.0+0x189/0x500 [ 48.453518][ T7181] ? ep_loop_check_proc+0x2f0/0x2f0 [ 48.458747][ T7181] ep_poll+0xe3/0x900 [ 48.462814][ T7181] ? __fget+0xb8/0x1d0 [ 48.466973][ T7181] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.472600][ T7181] ? __fget_light+0xaf/0x190 [ 48.477345][ T7181] do_epoll_wait+0x162/0x180 [ 48.482020][ T7181] __x64_sys_epoll_pwait+0xcd/0x180 [ 48.487326][ T7181] do_syscall_64+0xcc/0x370 [ 48.492393][ T7181] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.498479][ T7181] RIP: 0033:0x45b300 [ 48.502370][ T7181] 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 [ 48.522078][ T7181] RSP: 002b:000000c42004f8d8 EFLAGS: 00000246 ORIG_RAX: 0000000000000119 [ 48.530639][ T7181] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000045b300 [ 48.538634][ T7181] RDX: 0000000000000080 RSI: 000000c42004f918 RDI: 0000000000000004 [ 48.547500][ T7181] RBP: 000000c42004ff18 R08: 0000000000000000 R09: 0000000000002268 [ 48.555490][ T7181] R10: 0000000000000000 R11: 0000000000000246 R12: 000000000042f0a0 [ 48.563577][ T7181] R13: 00000000000000f1 R14: 0000000000000011 R15: 0000000000000000 [ 48.573202][ T7181] Kernel Offset: disabled [ 48.577571][ T7181] Rebooting in 86400 seconds..