[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 41.867840][ T26] audit: type=1800 audit(1570960995.200:25): pid=7045 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 41.887580][ T26] audit: type=1800 audit(1570960995.200:26): pid=7045 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 41.916710][ T26] audit: type=1800 audit(1570960995.200:27): pid=7045 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 '10.128.0.57' (ECDSA) to the list of known hosts. 2019/10/13 10:03:25 fuzzer started 2019/10/13 10:03:26 dialing manager at 10.128.0.105:40973 2019/10/13 10:03:26 syscalls: 2523 2019/10/13 10:03:26 code coverage: enabled 2019/10/13 10:03:26 comparison tracing: enabled 2019/10/13 10:03:26 extra coverage: extra coverage is not supported by the kernel 2019/10/13 10:03:26 setuid sandbox: enabled 2019/10/13 10:03:26 namespace sandbox: enabled 2019/10/13 10:03:26 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/13 10:03:26 fault injection: enabled 2019/10/13 10:03:26 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/13 10:03:26 net packet injection: enabled 2019/10/13 10:03:26 net device setup: enabled 2019/10/13 10:03:26 concurrency sanitizer: enabled syzkaller login: [ 53.883124][ T7204] ================================================================== [ 53.891271][ T7204] BUG: KCSAN: data-race in __zone_watermark_ok / get_page_from_freelist [ 53.899606][ T7204] [ 53.901936][ T7204] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 0: [ 53.909468][ T7204] __zone_watermark_ok+0x106/0x240 [ 53.914575][ T7204] get_page_from_freelist+0x629/0x2300 [ 53.920038][ T7204] __alloc_pages_nodemask+0x255/0x4d0 [ 53.925489][ T7204] page_frag_alloc+0x11e/0x2d0 [ 53.930241][ T7204] __napi_alloc_skb+0x172/0x210 [ 53.935081][ T7204] page_to_skb+0x8d/0x480 [ 53.939398][ T7204] receive_buf+0x17c7/0x30b0 [ 53.943986][ T7204] virtnet_poll+0x436/0x7d0 [ 53.948478][ T7204] net_rx_action+0x3ae/0xa50 [ 53.953055][ T7204] __do_softirq+0x115/0x33f [ 53.957556][ T7204] run_ksoftirqd+0x46/0x60 [ 53.961962][ T7204] smpboot_thread_fn+0x37d/0x4a0 [ 53.966882][ T7204] kthread+0x1d4/0x200 [ 53.970937][ T7204] ret_from_fork+0x1f/0x30 [ 53.975344][ T7204] [ 53.977670][ T7204] write to 0xffff88812fffcf58 of 8 bytes by task 7204 on cpu 1: [ 53.985299][ T7204] get_page_from_freelist+0x1217/0x2300 [ 53.990835][ T7204] __alloc_pages_nodemask+0x255/0x4d0 [ 53.996195][ T7204] alloc_pages_vma+0x15b/0x2b0 [ 54.000951][ T7204] __handle_mm_fault+0x17ac/0x2d00 [ 54.006048][ T7204] handle_mm_fault+0x21b/0x520 [ 54.010797][ T7204] __do_page_fault+0x3fb/0x9e0 [ 54.015550][ T7204] do_page_fault+0x54/0x233 [ 54.020039][ T7204] page_fault+0x34/0x40 [ 54.024172][ T7204] [ 54.026497][ T7204] Reported by Kernel Concurrency Sanitizer on: [ 54.032639][ T7204] CPU: 1 PID: 7204 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 54.039727][ T7204] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.049768][ T7204] ================================================================== [ 54.057827][ T7204] Kernel panic - not syncing: panic_on_warn set ... [ 54.064415][ T7204] CPU: 1 PID: 7204 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 54.071507][ T7204] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.081549][ T7204] Call Trace: [ 54.084834][ T7204] dump_stack+0xf5/0x159 [ 54.089067][ T7204] panic+0x209/0x639 [ 54.092950][ T7204] ? vprintk_func+0x8d/0x140 [ 54.097533][ T7204] kcsan_report.cold+0xc/0x1b [ 54.102202][ T7204] __kcsan_setup_watchpoint+0x3ee/0x510 [ 54.107737][ T7204] __tsan_write8+0x32/0x40 [ 54.112183][ T7204] get_page_from_freelist+0x1217/0x2300 [ 54.117746][ T7204] __alloc_pages_nodemask+0x255/0x4d0 [ 54.123113][ T7204] alloc_pages_vma+0x15b/0x2b0 [ 54.127954][ T7204] __handle_mm_fault+0x17ac/0x2d00 [ 54.133064][ T7204] handle_mm_fault+0x21b/0x520 [ 54.137838][ T7204] __do_page_fault+0x3fb/0x9e0 [ 54.142617][ T7204] do_page_fault+0x54/0x233 [ 54.147146][ T7204] ? prepare_exit_to_usermode+0x154/0x1a0 [ 54.152859][ T7204] page_fault+0x34/0x40 [ 54.157016][ T7204] RIP: 0033:0x45a84e [ 54.160904][ T7204] Code: f3 44 0f 6f 61 f0 c5 fe 6f 26 4c 01 de 48 29 c3 c5 fe 6f 06 c5 fe 6f 4e 20 c5 fe 6f 56 40 c5 fe 6f 5e 60 48 01 c6 c5 fd 7f 07 fd 7f 4f 20 c5 fd 7f 57 40 c5 fd 7f 5f 60 48 01 c7 48 29 c3 77 [ 54.180494][ T7204] RSP: 002b:000000c4204e7b58 EFLAGS: 00010202 [ 54.186546][ T7204] RAX: 0000000000000080 RBX: 0000000000004ee7 RCX: 000000c4204d2000 [ 54.194522][ T7204] RDX: 0000000000100bfc RSI: 000000c4204cd119 RDI: 000000c420ae7fe0 [ 54.202497][ T7204] RBP: 000000c4204e7b88 R08: 000000c4204ca000 R09: 0000000000008000 [ 54.210456][ T7204] R10: 000000c420ae4f47 R11: 0000000000000019 R12: 0000000000000040 [ 54.218430][ T7204] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 55.355216][ T7204] Shutting down cpus with NMI [ 55.361441][ T7204] Kernel Offset: disabled [ 55.365845][ T7204] Rebooting in 86400 seconds..