[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.665820][ T26] audit: type=1800 audit(1571339089.454:25): pid=7123 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.711415][ T26] audit: type=1800 audit(1571339089.464:26): pid=7123 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.737614][ T26] audit: type=1800 audit(1571339089.464:27): pid=7123 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 '10.128.0.192' (ECDSA) to the list of known hosts. 2019/10/17 19:04:57 fuzzer started 2019/10/17 19:04:59 dialing manager at 10.128.0.105:43535 2019/10/17 19:04:59 syscalls: 2524 2019/10/17 19:04:59 code coverage: enabled 2019/10/17 19:04:59 comparison tracing: enabled 2019/10/17 19:04:59 extra coverage: extra coverage is not supported by the kernel 2019/10/17 19:04:59 setuid sandbox: enabled 2019/10/17 19:04:59 namespace sandbox: enabled 2019/10/17 19:04:59 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/17 19:04:59 fault injection: enabled 2019/10/17 19:04:59 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/17 19:04:59 net packet injection: enabled 2019/10/17 19:04:59 net device setup: enabled 2019/10/17 19:04:59 concurrency sanitizer: enabled syzkaller login: [ 48.206164][ C0] ================================================================== [ 48.214423][ C0] BUG: KCSAN: data-race in tick_do_update_jiffies64 / tick_do_update_jiffies64 [ 48.224346][ C0] [ 48.227129][ C0] write to 0xffffffff86042008 of 8 bytes by interrupt on cpu 1: [ 48.234772][ C0] tick_do_update_jiffies64+0x105/0x260 [ 48.240347][ C0] tick_sched_do_timer+0xd4/0xe0 [ 48.245647][ C0] tick_sched_timer+0x43/0xe0 [ 48.250326][ C0] __hrtimer_run_queues+0x288/0x600 [ 48.255526][ C0] hrtimer_interrupt+0x22a/0x480 [ 48.260467][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 48.265926][ C0] apic_timer_interrupt+0xf/0x20 [ 48.270843][ C0] __sanitizer_cov_trace_pc+0x1a/0x50 [ 48.276428][ C0] skb_try_coalesce+0x468/0xbf0 [ 48.281349][ C0] tcp_add_backlog+0x72b/0xcc0 [ 48.286098][ C0] tcp_v4_rcv+0x1a60/0x1bb0 [ 48.290604][ C0] ip_protocol_deliver_rcu+0x4d/0x420 [ 48.295973][ C0] ip_local_deliver_finish+0x110/0x140 [ 48.301701][ C0] ip_local_deliver+0x133/0x210 [ 48.306628][ C0] [ 48.308962][ C0] read to 0xffffffff86042008 of 8 bytes by interrupt on cpu 0: [ 48.316753][ C0] tick_do_update_jiffies64+0x2b/0x260 [ 48.322302][ C0] tick_sched_do_timer+0xd4/0xe0 [ 48.327236][ C0] tick_sched_timer+0x43/0xe0 [ 48.331928][ C0] __hrtimer_run_queues+0x288/0x600 [ 48.337198][ C0] hrtimer_interrupt+0x22a/0x480 [ 48.342136][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 48.348224][ C0] apic_timer_interrupt+0xf/0x20 [ 48.353156][ C0] __kcsan_setup_watchpoint+0x0/0x4a0 [ 48.358611][ C0] detach_buf_split+0x197/0x3d0 [ 48.363440][ C0] virtqueue_get_buf_ctx+0x4b4/0x5c0 [ 48.368705][ C0] virtqueue_get_buf+0x29/0x40 [ 48.373466][ C0] free_old_xmit_skbs+0x9e/0x170 [ 48.378393][ C0] start_xmit+0xd3/0xbe0 [ 48.382626][ C0] [ 48.384927][ C0] Reported by Kernel Concurrency Sanitizer on: [ 48.391418][ C0] CPU: 0 PID: 7278 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.398846][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.408876][ C0] ================================================================== [ 48.417086][ C0] Kernel panic - not syncing: panic_on_warn set ... [ 48.423677][ C0] CPU: 0 PID: 7278 Comm: syz-fuzzer Not tainted 5.4.0-rc3+ #0 [ 48.431216][ C0] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.441277][ C0] Call Trace: [ 48.444543][ C0] [ 48.447394][ C0] dump_stack+0xf5/0x159 [ 48.451640][ C0] panic+0x210/0x640 [ 48.455547][ C0] ? detach_buf_split+0x197/0x3d0 [ 48.460578][ C0] ? vprintk_func+0x8d/0x140 [ 48.465167][ C0] kcsan_report.cold+0xc/0x10 [ 48.469843][ C0] __kcsan_setup_watchpoint+0x32e/0x4a0 [ 48.475448][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.481088][ C0] __tsan_read8+0x2c/0x30 [ 48.485480][ C0] tick_do_update_jiffies64+0x2b/0x260 [ 48.490978][ C0] tick_sched_do_timer+0xd4/0xe0 [ 48.495902][ C0] tick_sched_timer+0x43/0xe0 [ 48.500559][ C0] __hrtimer_run_queues+0x288/0x600 [ 48.505753][ C0] ? tick_sched_do_timer+0xe0/0xe0 [ 48.510858][ C0] hrtimer_interrupt+0x22a/0x480 [ 48.515797][ C0] smp_apic_timer_interrupt+0xdc/0x280 [ 48.521236][ C0] ? smp_reschedule_interrupt+0x71/0x1d0 [ 48.526861][ C0] apic_timer_interrupt+0xf/0x20 [ 48.531773][ C0] [ 48.534712][ C0] RIP: 0010:__kcsan_setup_watchpoint+0x0/0x4a0 [ 48.540845][ C0] Code: 44 89 e2 4c 89 f6 4c 89 ef e8 8c 0e 00 00 66 90 31 c0 eb b6 c3 bf 04 00 00 00 41 bf 02 00 00 00 e8 45 0b 00 00 eb c5 0f 1f 00 <55> 48 89 e5 41 57 41 56 49 89 fe 41 55 41 54 49 89 f4 53 89 d3 48 [ 48.560444][ C0] RSP: 0018:ffffc900015572f0 EFLAGS: 00000246 ORIG_RAX: ffffffffffffff13 [ 48.568834][ C0] RAX: 0000000000000001 RBX: 0000000000000010 RCX: 0000000000000003 [ 48.576822][ C0] RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff888128c9fe80 [ 48.584778][ C0] RBP: ffffc90001557300 R08: 0000000000000000 R09: 0000888128c9fe83 [ 48.592748][ C0] R10: 00000000aaaaaaab R11: ffffffff86045d10 R12: ffff888128c9fe80 [ 48.600700][ C0] R13: ffff888128c9fe40 R14: 0000000000000000 R15: ffff888128c9fe6c [ 48.608679][ C0] ? __tsan_read4+0x2c/0x30 [ 48.613170][ C0] detach_buf_split+0x197/0x3d0 [ 48.618091][ C0] virtqueue_get_buf_ctx+0x4b4/0x5c0 [ 48.623625][ C0] virtqueue_get_buf+0x29/0x40 [ 48.628454][ C0] free_old_xmit_skbs+0x9e/0x170 [ 48.633402][ C0] start_xmit+0xd3/0xbe0 [ 48.637639][ C0] dev_hard_start_xmit+0xef/0x430 [ 48.642775][ C0] sch_direct_xmit+0x2b3/0x870 [ 48.647567][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.653440][ C0] __dev_queue_xmit+0x19c6/0x1b60 [ 48.658449][ C0] ? ipt_do_table+0x8e9/0xe60 [ 48.663116][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.668750][ C0] ? __rcu_read_unlock+0x66/0x3c0 [ 48.673778][ C0] ? __kcsan_setup_watchpoint+0x6b/0x4a0 [ 48.679420][ C0] dev_queue_xmit+0x21/0x30 [ 48.683922][ C0] ip_finish_output2+0x83a/0xe40 [ 48.688874][ C0] __ip_finish_output+0x23a/0x490 [ 48.693975][ C0] ? __tsan_write4+0x32/0x40 [ 48.698575][ C0] ip_finish_output+0x41/0x160 [ 48.703324][ C0] ip_output+0xdf/0x210 [ 48.707478][ C0] ? __ip_finish_output+0x490/0x490 [ 48.712675][ C0] ip_local_out+0x74/0x90 [ 48.716992][ C0] __ip_queue_xmit+0x3a8/0xa40 [ 48.721750][ C0] ip_queue_xmit+0x45/0x60 [ 48.726173][ C0] __tcp_transmit_skb+0xe81/0x1d60 [ 48.731270][ C0] __tcp_send_ack+0x246/0x300 [ 48.735927][ C0] tcp_send_ack+0x34/0x40 [ 48.740236][ C0] tcp_cleanup_rbuf+0x130/0x360 [ 48.745065][ C0] tcp_recvmsg+0x633/0x1a30 [ 48.749568][ C0] inet_recvmsg+0xbb/0x250 [ 48.754081][ C0] ? __tsan_read8+0x2c/0x30 [ 48.758568][ C0] ? inet_sendpage+0x100/0x100 [ 48.763316][ C0] sock_recvmsg+0x92/0xb0 [ 48.767627][ C0] sock_read_iter+0x15f/0x1e0 [ 48.772303][ C0] new_sync_read+0x389/0x4f0 [ 48.776876][ C0] __vfs_read+0xb1/0xc0 [ 48.781011][ C0] vfs_read+0x143/0x2c0 [ 48.785149][ C0] ksys_read+0xd5/0x1b0 [ 48.789287][ C0] __x64_sys_read+0x4c/0x60 [ 48.793788][ C0] do_syscall_64+0xcc/0x370 [ 48.798282][ C0] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 48.804158][ C0] RIP: 0033:0x47c530 [ 48.808034][ C0] 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 [ 48.827652][ C0] RSP: 002b:000000c4205507d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 48.836492][ C0] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 48.844452][ C0] RDX: 0000000000001000 RSI: 000000c420176000 RDI: 0000000000000003 [ 48.852412][ C0] RBP: 000000c420550830 R08: 0000000000000000 R09: 0000000000000000 [ 48.860362][ C0] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 48.868310][ C0] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 48.877580][ C0] Kernel Offset: disabled [ 48.881920][ C0] Rebooting in 86400 seconds..