[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 34.144184][ T26] audit: type=1800 audit(1571153110.213:25): pid=7023 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 34.183196][ T26] audit: type=1800 audit(1571153110.213:26): pid=7023 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 34.205755][ T26] audit: type=1800 audit(1571153110.213:27): pid=7023 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 '10.128.10.39' (ECDSA) to the list of known hosts. 2019/10/15 15:25:18 fuzzer started 2019/10/15 15:25:19 dialing manager at 10.128.0.105:38903 2019/10/15 15:25:20 syscalls: 2523 2019/10/15 15:25:20 code coverage: enabled 2019/10/15 15:25:20 comparison tracing: enabled 2019/10/15 15:25:20 extra coverage: extra coverage is not supported by the kernel 2019/10/15 15:25:20 setuid sandbox: enabled 2019/10/15 15:25:20 namespace sandbox: enabled 2019/10/15 15:25:20 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/15 15:25:20 fault injection: enabled 2019/10/15 15:25:20 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/15 15:25:20 net packet injection: enabled 2019/10/15 15:25:20 net device setup: enabled 2019/10/15 15:25:20 concurrency sanitizer: enabled syzkaller login: [ 44.586851][ C1] ================================================================== [ 44.594973][ C1] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 44.602524][ C1] [ 44.604830][ C1] write to 0xffff88812fffcf58 of 8 bytes by task 7186 on cpu 0: [ 44.612433][ C1] free_one_page+0x214/0x840 [ 44.616996][ C1] __free_pages_ok+0x370/0x640 [ 44.621734][ C1] free_compound_page+0x3d/0x50 [ 44.626560][ C1] __put_compound_page+0x4e/0x70 [ 44.631470][ C1] __put_page+0x54/0xd0 [ 44.635638][ C1] skb_release_data+0x1ba/0x3a0 [ 44.640465][ C1] skb_release_all+0x44/0x60 [ 44.645039][ C1] __kfree_skb+0x1f/0x30 [ 44.649257][ C1] tcp_recvmsg+0xf59/0x1a30 [ 44.653739][ C1] inet_recvmsg+0xbb/0x250 [ 44.658130][ C1] sock_recvmsg+0x92/0xb0 [ 44.662435][ C1] sock_read_iter+0x15f/0x1e0 [ 44.667087][ C1] new_sync_read+0x389/0x4f0 [ 44.671651][ C1] __vfs_read+0xb1/0xc0 [ 44.675809][ C1] [ 44.678116][ C1] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1: [ 44.685635][ C1] __zone_watermark_ok+0x106/0x240 [ 44.690754][ C1] get_page_from_freelist+0x629/0x2300 [ 44.696274][ C1] __alloc_pages_nodemask+0x255/0x4d0 [ 44.701629][ C1] alloc_pages_current+0xd1/0x170 [ 44.706643][ C1] skb_page_frag_refill+0x16f/0x260 [ 44.711829][ C1] try_fill_recv+0x51f/0xdc0 [ 44.716394][ C1] virtnet_poll+0x64c/0x7d0 [ 44.720883][ C1] net_rx_action+0x3ae/0xa50 [ 44.725461][ C1] __do_softirq+0x115/0x33f [ 44.729937][ C1] run_ksoftirqd+0x46/0x60 [ 44.734326][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 44.739238][ C1] kthread+0x1d4/0x200 [ 44.743277][ C1] ret_from_fork+0x1f/0x30 [ 44.747662][ C1] [ 44.749965][ C1] Reported by Kernel Concurrency Sanitizer on: [ 44.756093][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 44.763084][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.773124][ C1] ================================================================== [ 44.781165][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 44.787733][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 44.794740][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 44.804780][ C1] Call Trace: [ 44.808059][ C1] dump_stack+0xf5/0x159 [ 44.812279][ C1] panic+0x209/0x639 [ 44.816162][ C1] ? __do_softirq+0x115/0x33f [ 44.820821][ C1] ? vprintk_func+0x8d/0x140 [ 44.825389][ C1] kcsan_report.cold+0xc/0x1b [ 44.830056][ C1] __kcsan_setup_watchpoint+0x3ee/0x510 [ 44.835578][ C1] __tsan_read8+0x2c/0x30 [ 44.839883][ C1] __zone_watermark_ok+0x106/0x240 [ 44.844976][ C1] get_page_from_freelist+0x629/0x2300 [ 44.850427][ C1] ? __sanitizer_cov_trace_const_cmp4+0x16/0x20 [ 44.856658][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 44.862264][ C1] ? __tsan_read8+0x2c/0x30 [ 44.866743][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 44.872956][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 44.878566][ C1] __alloc_pages_nodemask+0x255/0x4d0 [ 44.883918][ C1] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20 [ 44.890132][ C1] alloc_pages_current+0xd1/0x170 [ 44.895134][ C1] skb_page_frag_refill+0x16f/0x260 [ 44.900316][ C1] try_fill_recv+0x51f/0xdc0 [ 44.904892][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 44.910503][ C1] virtnet_poll+0x64c/0x7d0 [ 44.914985][ C1] net_rx_action+0x3ae/0xa50 [ 44.919569][ C1] __do_softirq+0x115/0x33f [ 44.924049][ C1] ? takeover_tasklets+0x250/0x250 [ 44.929132][ C1] run_ksoftirqd+0x46/0x60 [ 44.933521][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 44.938436][ C1] kthread+0x1d4/0x200 [ 44.942480][ C1] ? constant_test_bit.constprop.0+0x30/0x30 [ 44.948435][ C1] ? kthread_bind+0x50/0x50 [ 44.952912][ C1] ret_from_fork+0x1f/0x30 [ 44.958567][ C1] Kernel Offset: disabled [ 44.962885][ C1] Rebooting in 86400 seconds..