[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.352863][ T26] audit: type=1800 audit(1571730982.745:25): pid=7107 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.387515][ T26] audit: type=1800 audit(1571730982.745:26): pid=7107 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.407988][ T26] audit: type=1800 audit(1571730982.745:27): pid=7107 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 '10.128.0.112' (ECDSA) to the list of known hosts. 2019/10/22 07:56:30 fuzzer started 2019/10/22 07:56:32 dialing manager at 10.128.0.105:37053 2019/10/22 07:56:32 syscalls: 2524 2019/10/22 07:56:32 code coverage: enabled 2019/10/22 07:56:32 comparison tracing: enabled 2019/10/22 07:56:32 extra coverage: extra coverage is not supported by the kernel 2019/10/22 07:56:32 setuid sandbox: enabled 2019/10/22 07:56:32 namespace sandbox: enabled 2019/10/22 07:56:32 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/22 07:56:32 fault injection: enabled 2019/10/22 07:56:32 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/22 07:56:32 net packet injection: enabled 2019/10/22 07:56:32 net device setup: enabled 2019/10/22 07:56:32 concurrency sanitizer: enabled syzkaller login: [ 44.369230][ T7276] ================================================================== [ 44.377369][ T7276] BUG: KCSAN: data-race in __nf_conntrack_find_get / __nf_ct_refresh_acct [ 44.385847][ T7276] [ 44.388155][ T7276] read to 0xffff8881233f1508 of 4 bytes by interrupt on cpu 0: [ 44.395677][ T7276] __nf_conntrack_find_get+0x284/0x880 [ 44.401111][ T7276] nf_conntrack_in+0x2ef/0xa80 [ 44.405849][ T7276] ipv4_conntrack_in+0x27/0x40 [ 44.410588][ T7276] nf_hook_slow+0x83/0x160 [ 44.414985][ T7276] ip_rcv+0x12f/0x1a0 [ 44.418944][ T7276] __netif_receive_skb_one_core+0xa7/0xe0 [ 44.424678][ T7276] __netif_receive_skb+0x37/0xf0 [ 44.429633][ T7276] netif_receive_skb_internal+0x59/0x190 [ 44.435247][ T7276] napi_gro_receive+0x28f/0x330 [ 44.440109][ T7276] receive_buf+0x284/0x30b0 [ 44.444586][ T7276] virtnet_poll+0x436/0x7d0 [ 44.449066][ T7276] net_rx_action+0x3ae/0xa90 [ 44.453637][ T7276] __do_softirq+0x115/0x33f [ 44.458161][ T7276] irq_exit+0xbb/0xe0 [ 44.462112][ T7276] [ 44.464428][ T7276] write to 0xffff8881233f1508 of 4 bytes by task 7276 on cpu 1: [ 44.472039][ T7276] __nf_ct_refresh_acct+0xfb/0x1b0 [ 44.477124][ T7276] nf_conntrack_tcp_packet+0xd40/0x3390 [ 44.482653][ T7276] nf_conntrack_in+0x410/0xa80 [ 44.487392][ T7276] ipv4_conntrack_local+0xbe/0x130 [ 44.492477][ T7276] nf_hook_slow+0x83/0x160 [ 44.496877][ T7276] __ip_local_out+0x1f7/0x2b0 [ 44.501536][ T7276] ip_local_out+0x31/0x90 [ 44.505838][ T7276] __ip_queue_xmit+0x3a8/0xa40 [ 44.510588][ T7276] ip_queue_xmit+0x45/0x60 [ 44.515001][ T7276] __tcp_transmit_skb+0xe81/0x1d60 [ 44.520094][ T7276] __tcp_send_ack+0x246/0x300 [ 44.524754][ T7276] tcp_send_ack+0x34/0x40 [ 44.529059][ T7276] tcp_cleanup_rbuf+0x130/0x360 [ 44.533888][ T7276] [ 44.536191][ T7276] Reported by Kernel Concurrency Sanitizer on: [ 44.542322][ T7276] CPU: 1 PID: 7276 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.549748][ T7276] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.559952][ T7276] ================================================================== [ 44.567988][ T7276] Kernel panic - not syncing: panic_on_warn set ... [ 44.574741][ T7276] CPU: 1 PID: 7276 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 44.582165][ T7276] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.592192][ T7276] Call Trace: [ 44.595464][ T7276] dump_stack+0xf5/0x159 [ 44.599683][ T7276] panic+0x210/0x640 [ 44.603566][ T7276] ? ip_queue_xmit+0x45/0x60 [ 44.608132][ T7276] ? vprintk_func+0x8d/0x140 [ 44.612712][ T7276] kcsan_report.cold+0xc/0x10 [ 44.617367][ T7276] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 44.622894][ T7276] __tsan_write4+0x32/0x40 [ 44.627288][ T7276] __nf_ct_refresh_acct+0xfb/0x1b0 [ 44.632376][ T7276] nf_conntrack_tcp_packet+0xd40/0x3390 [ 44.637904][ T7276] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 44.643527][ T7276] nf_conntrack_in+0x410/0xa80 [ 44.648270][ T7276] ipv4_conntrack_local+0xbe/0x130 [ 44.653359][ T7276] nf_hook_slow+0x83/0x160 [ 44.657747][ T7276] ? nf_ct_tcp_fixup+0xe0/0xe0 [ 44.662487][ T7276] __ip_local_out+0x1f7/0x2b0 [ 44.667139][ T7276] ? constant_test_bit+0x30/0x30 [ 44.672053][ T7276] ip_local_out+0x31/0x90 [ 44.676356][ T7276] __ip_queue_xmit+0x3a8/0xa40 [ 44.681099][ T7276] ip_queue_xmit+0x45/0x60 [ 44.685495][ T7276] __tcp_transmit_skb+0xe81/0x1d60 [ 44.690589][ T7276] __tcp_send_ack+0x246/0x300 [ 44.695251][ T7276] tcp_send_ack+0x34/0x40 [ 44.699562][ T7276] tcp_cleanup_rbuf+0x130/0x360 [ 44.704411][ T7276] tcp_recvmsg+0x633/0x1a30 [ 44.708938][ T7276] inet_recvmsg+0xbb/0x250 [ 44.713340][ T7276] ? __tsan_read8+0x2c/0x30 [ 44.717835][ T7276] ? inet_sendpage+0x100/0x100 [ 44.722589][ T7276] sock_recvmsg+0x92/0xb0 [ 44.726907][ T7276] sock_read_iter+0x15f/0x1e0 [ 44.731567][ T7276] new_sync_read+0x389/0x4f0 [ 44.736151][ T7276] __vfs_read+0xb1/0xc0 [ 44.740286][ T7276] vfs_read+0x143/0x2c0 [ 44.744607][ T7276] ksys_read+0xd5/0x1b0 [ 44.748754][ T7276] __x64_sys_read+0x4c/0x60 [ 44.753284][ T7276] do_syscall_64+0xcc/0x370 [ 44.757808][ T7276] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 44.763722][ T7276] RIP: 0033:0x47c530 [ 44.767598][ T7276] 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 [ 44.787174][ T7276] RSP: 002b:000000c4202ed8c0 EFLAGS: 00000206 ORIG_RAX: 0000000000000000 [ 44.795558][ T7276] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 44.803504][ T7276] RDX: 0000000000001000 RSI: 000000c420318000 RDI: 0000000000000003 [ 44.811546][ T7276] RBP: 000000c4202ed918 R08: 0000000000000000 R09: 0000000000000000 [ 44.819502][ T7276] R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000109 [ 44.827447][ T7276] R13: 0000000000000108 R14: 0000000000000200 R15: ffffffffffffffff [ 44.836624][ T7276] Kernel Offset: disabled [ 44.840947][ T7276] Rebooting in 86400 seconds..