[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
[ 35.695560][ T25] audit: type=1800 audit(1570960719.571:25): pid=7180 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0
[ 35.723220][ T25] audit: type=1800 audit(1570960719.571:26): pid=7180 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0
[ 35.750299][ T25] audit: type=1800 audit(1570960719.571:27): pid=7180 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[1G[[32m ok [39;49m8[?25h[?0c.
[....] Starting OpenBSD Secure Shell server: sshd[?25l[?1c7[1G[[32m ok [39;49m8[?25h[?0c.
Debian GNU/Linux 7 syzkaller ttyS0
Warning: Permanently added '10.128.1.11' (ECDSA) to the list of known hosts.
2019/10/13 09:58:48 fuzzer started
2019/10/13 09:58:49 dialing manager at 10.128.0.105:40973
2019/10/13 09:58:49 syscalls: 2523
2019/10/13 09:58:49 code coverage: enabled
2019/10/13 09:58:49 comparison tracing: enabled
2019/10/13 09:58:49 extra coverage: extra coverage is not supported by the kernel
2019/10/13 09:58:49 setuid sandbox: enabled
2019/10/13 09:58:49 namespace sandbox: enabled
2019/10/13 09:58:49 Android sandbox: /sys/fs/selinux/policy does not exist
2019/10/13 09:58:49 fault injection: enabled
2019/10/13 09:58:49 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled
2019/10/13 09:58:49 net packet injection: enabled
2019/10/13 09:58:49 net device setup: enabled
2019/10/13 09:58:49 concurrency sanitizer: enabled
syzkaller login: [ 46.260416][ C1] ==================================================================
[ 46.268814][ C1] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page
[ 46.276405][ C1]
[ 46.278730][ C1] write to 0xffff88812fffcf58 of 8 bytes by task 7344 on cpu 0:
[ 46.286344][ C1] free_one_page+0x783/0x840
[ 46.290918][ C1] __free_pages_ok+0x370/0x640
[ 46.295665][ C1] free_compound_page+0x3d/0x50
[ 46.300498][ C1] __put_compound_page+0x4e/0x70
[ 46.305424][ C1] __put_page+0x54/0xd0
[ 46.309564][ C1] skb_release_data+0x1ba/0x3a0
[ 46.314402][ C1] skb_release_all+0x44/0x60
[ 46.318975][ C1] __kfree_skb+0x1f/0x30
[ 46.323209][ C1] tcp_recvmsg+0xf59/0x1a30
[ 46.327697][ C1] inet_recvmsg+0xbb/0x250
[ 46.332093][ C1] sock_recvmsg+0x92/0xb0
[ 46.336408][ C1] sock_read_iter+0x15f/0x1e0
[ 46.341069][ C1] new_sync_read+0x389/0x4f0
[ 46.345640][ C1] __vfs_read+0xb1/0xc0
[ 46.349772][ C1]
[ 46.352120][ C1] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1:
[ 46.359669][ C1] __zone_watermark_ok+0x106/0x240
[ 46.364764][ C1] get_page_from_freelist+0x629/0x2300
[ 46.370210][ C1] __alloc_pages_nodemask+0x255/0x4d0
[ 46.375570][ C1] alloc_pages_current+0xd1/0x170
[ 46.380586][ C1] skb_page_frag_refill+0x16f/0x260
[ 46.385770][ C1] try_fill_recv+0x51f/0xdc0
[ 46.390347][ C1] virtnet_poll+0x64c/0x7d0
[ 46.394950][ C1] net_rx_action+0x3ae/0xa50
[ 46.399714][ C1] __do_softirq+0x115/0x33f
[ 46.404203][ C1] irq_exit+0xbb/0xe0
[ 46.408167][ C1] do_IRQ+0xdf/0x150
[ 46.412045][ C1] ret_from_intr+0x0/0x19
[ 46.416464][ C1] native_safe_halt+0xe/0x10
[ 46.421143][ C1]
[ 46.423454][ C1] Reported by Kernel Concurrency Sanitizer on:
[ 46.429591][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
[ 46.436328][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 46.446367][ C1] ==================================================================
[ 46.454407][ C1] Kernel panic - not syncing: panic_on_warn set ...
[ 46.460993][ C1] CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.3.0+ #0
[ 46.467733][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
[ 46.477771][ C1] Call Trace:
[ 46.481052][ C1]
[ 46.483896][ C1] dump_stack+0xf5/0x159
[ 46.488134][ C1] panic+0x209/0x639
[ 46.492012][ C1] ? __do_softirq+0x115/0x33f
[ 46.496678][ C1] ? vprintk_func+0x8d/0x140
[ 46.501260][ C1] kcsan_report.cold+0xc/0x1b
[ 46.505923][ C1] __kcsan_setup_watchpoint+0x3ee/0x510
[ 46.511453][ C1] __tsan_read8+0x2c/0x30
[ 46.515802][ C1] __zone_watermark_ok+0x106/0x240
[ 46.520903][ C1] get_page_from_freelist+0x629/0x2300
[ 46.526351][ C1] ? __kcsan_setup_watchpoint+0x96/0x510
[ 46.531966][ C1] ? __tsan_read8+0x2c/0x30
[ 46.536489][ C1] ? __sanitizer_cov_trace_const_cmp8+0x18/0x20
[ 46.542713][ C1] ? __kcsan_setup_watchpoint+0x96/0x510
[ 46.548332][ C1] __alloc_pages_nodemask+0x255/0x4d0
[ 46.553693][ C1] ? __sanitizer_cov_trace_const_cmp2+0x18/0x20
[ 46.559951][ C1] alloc_pages_current+0xd1/0x170
[ 46.564967][ C1] skb_page_frag_refill+0x16f/0x260
[ 46.570185][ C1] try_fill_recv+0x51f/0xdc0
[ 46.574793][ C1] ? __kcsan_setup_watchpoint+0x96/0x510
[ 46.580412][ C1] virtnet_poll+0x64c/0x7d0
[ 46.584935][ C1] net_rx_action+0x3ae/0xa50
[ 46.589515][ C1] __do_softirq+0x115/0x33f
[ 46.594006][ C1] irq_exit+0xbb/0xe0
[ 46.597971][ C1] do_IRQ+0xdf/0x150
[ 46.601850][ C1] common_interrupt+0xf/0xf
[ 46.606336][ C1]
[ 46.609263][ C1] RIP: 0010:native_safe_halt+0xe/0x10
[ 46.614630][ C1] Code: 90 90 90 90 90 90 90 90 90 90 90 90 e9 07 00 00 00 0f 00 2d 8c d2 4e 00 f4 c3 66 90 e9 07 00 00 00 0f 00 2d 7c d2 4e 00 fb f4 90 55 48 89 e5 41 55 41 54 53 e8 82 78 a7 fc e8 5d 52 b9 fd 0f
[ 46.634307][ C1] RSP: 0018:ffffc90000cd3e48 EFLAGS: 00000282 ORIG_RAX: ffffffffffffffde
[ 46.642745][ C1] RAX: 9db22d0e56043a74 RBX: 0000000000000001 RCX: 00000000000004d0
[ 46.650702][ C1] RDX: 00000000001d6370 RSI: 020c49ba5e353f7d RDI: ffffffff85a55a28
[ 46.658656][ C1] RBP: ffffc90000cd3e80 R08: 0000000000000000 R09: 0000ffff85a55a2f
[ 46.666654][ C1] R10: 00000000aaaaaaab R11: ffffffff86042cc0 R12: ffff88812b38f0c0
[ 46.674611][ C1] R13: ffff88812b38f0c0 R14: 0000000000000000 R15: 0000000000000000
[ 46.682620][ C1] ? default_idle+0x50/0x230
[ 46.687235][ C1] arch_cpu_idle+0x1f/0x30
[ 46.691642][ C1] default_idle_call+0x1e/0x40
[ 46.696394][ C1] do_idle+0x1ea/0x2c0
[ 46.700448][ C1] ? complete+0x44/0x50
[ 46.704624][ C1] cpu_startup_entry+0x1b/0x20
[ 46.709406][ C1] start_secondary+0x207/0x260
[ 46.714189][ C1] secondary_startup_64+0xa4/0xb0
[ 46.720766][ C1] Kernel Offset: disabled
[ 46.725115][ C1] Rebooting in 86400 seconds..