[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.030420][ T26] audit: type=1800 audit(1571120281.695:25): pid=7116 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.050402][ T26] audit: type=1800 audit(1571120281.695:26): pid=7116 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.070364][ T26] audit: type=1800 audit(1571120281.695:27): pid=7116 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 '10.128.0.210' (ECDSA) to the list of known hosts. 2019/10/15 06:18:12 fuzzer started 2019/10/15 06:18:13 dialing manager at 10.128.0.105:33683 2019/10/15 06:18:13 syscalls: 2523 2019/10/15 06:18:13 code coverage: enabled 2019/10/15 06:18:13 comparison tracing: enabled 2019/10/15 06:18:13 extra coverage: extra coverage is not supported by the kernel 2019/10/15 06:18:13 setuid sandbox: enabled 2019/10/15 06:18:13 namespace sandbox: enabled 2019/10/15 06:18:13 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/15 06:18:13 fault injection: enabled 2019/10/15 06:18:13 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/15 06:18:13 net packet injection: enabled 2019/10/15 06:18:13 net device setup: enabled 2019/10/15 06:18:13 concurrency sanitizer: enabled syzkaller login: [ 48.020539][ C1] ================================================================== [ 48.028792][ C1] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 48.036436][ C1] [ 48.038750][ C1] write to 0xffff88812fffcf58 of 8 bytes by task 7269 on cpu 0: [ 48.046463][ C1] free_one_page+0x214/0x840 [ 48.051035][ C1] __free_pages_ok+0x370/0x640 [ 48.055806][ C1] free_compound_page+0x3d/0x50 [ 48.060649][ C1] __put_compound_page+0x4e/0x70 [ 48.065589][ C1] __put_page+0x54/0xd0 [ 48.070003][ C1] skb_release_data+0x1ba/0x3a0 [ 48.074848][ C1] skb_release_all+0x44/0x60 [ 48.079420][ C1] __kfree_skb+0x1f/0x30 [ 48.083774][ C1] tcp_recvmsg+0xf59/0x1a30 [ 48.088264][ C1] inet_recvmsg+0xbb/0x250 [ 48.092714][ C1] sock_recvmsg+0x92/0xb0 [ 48.097035][ C1] sock_read_iter+0x15f/0x1e0 [ 48.101706][ C1] new_sync_read+0x389/0x4f0 [ 48.106281][ C1] __vfs_read+0xb1/0xc0 [ 48.110424][ C1] [ 48.112754][ C1] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1: [ 48.120971][ C1] __zone_watermark_ok+0x106/0x240 [ 48.126063][ C1] get_page_from_freelist+0x629/0x2300 [ 48.131513][ C1] __alloc_pages_nodemask+0x255/0x4d0 [ 48.136885][ C1] page_frag_alloc+0x11e/0x2d0 [ 48.141625][ C1] __napi_alloc_skb+0x172/0x210 [ 48.146471][ C1] page_to_skb+0x8d/0x480 [ 48.150777][ C1] receive_buf+0x17c7/0x30b0 [ 48.155346][ C1] virtnet_poll+0x436/0x7d0 [ 48.159920][ C1] net_rx_action+0x3ae/0xa50 [ 48.164517][ C1] __do_softirq+0x115/0x33f [ 48.169019][ C1] run_ksoftirqd+0x46/0x60 [ 48.174008][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 48.178988][ C1] kthread+0x1d4/0x200 [ 48.183039][ C1] [ 48.185347][ C1] Reported by Kernel Concurrency Sanitizer on: [ 48.192441][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 48.199992][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.210149][ C1] ================================================================== [ 48.218218][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 48.224976][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0+ #0 [ 48.231984][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 48.242033][ C1] Call Trace: [ 48.246421][ C1] dump_stack+0xf5/0x159 [ 48.250657][ C1] panic+0x209/0x639 [ 48.254550][ C1] ? net_rx_action+0x3ae/0xa50 [ 48.259292][ C1] ? vprintk_func+0x8d/0x140 [ 48.263866][ C1] kcsan_report.cold+0xc/0x1b [ 48.268551][ C1] __kcsan_setup_watchpoint+0x3ee/0x510 [ 48.274214][ C1] __tsan_read8+0x2c/0x30 [ 48.278571][ C1] __zone_watermark_ok+0x106/0x240 [ 48.283712][ C1] get_page_from_freelist+0x629/0x2300 [ 48.289172][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.294794][ C1] ? __tsan_read8+0x2c/0x30 [ 48.299281][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20 [ 48.305502][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.311149][ C1] __alloc_pages_nodemask+0x255/0x4d0 [ 48.316519][ C1] page_frag_alloc+0x11e/0x2d0 [ 48.321279][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.326897][ C1] __napi_alloc_skb+0x172/0x210 [ 48.331742][ C1] page_to_skb+0x8d/0x480 [ 48.336430][ C1] receive_buf+0x17c7/0x30b0 [ 48.341018][ C1] ? __tsan_write8+0x32/0x40 [ 48.345598][ C1] ? virtqueue_get_buf_ctx+0x4fd/0x5c0 [ 48.351041][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.356665][ C1] ? __kcsan_setup_watchpoint+0x96/0x510 [ 48.362290][ C1] virtnet_poll+0x436/0x7d0 [ 48.366788][ C1] net_rx_action+0x3ae/0xa50 [ 48.371380][ C1] __do_softirq+0x115/0x33f [ 48.375868][ C1] ? takeover_tasklets+0x250/0x250 [ 48.380967][ C1] run_ksoftirqd+0x46/0x60 [ 48.385367][ C1] smpboot_thread_fn+0x37d/0x4a0 [ 48.390385][ C1] kthread+0x1d4/0x200 [ 48.394436][ C1] ? constant_test_bit.constprop.0+0x30/0x30 [ 48.400395][ C1] ? kthread_bind+0x50/0x50 [ 48.404976][ C1] ret_from_fork+0x1f/0x30 [ 48.411946][ C1] Kernel Offset: disabled [ 48.416477][ C1] Rebooting in 86400 seconds..