[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 35.876122][ T25] audit: type=1800 audit(1571053430.750:25): pid=7016 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 35.903174][ T25] audit: type=1800 audit(1571053430.750:26): pid=7016 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 35.929946][ T25] audit: type=1800 audit(1571053430.750:27): pid=7016 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 '10.128.0.162' (ECDSA) to the list of known hosts. 2019/10/14 11:43:59 fuzzer started 2019/10/14 11:44:00 dialing manager at 10.128.0.105:43961 2019/10/14 11:44:00 syscalls: 2523 2019/10/14 11:44:00 code coverage: enabled 2019/10/14 11:44:00 comparison tracing: enabled 2019/10/14 11:44:00 extra coverage: extra coverage is not supported by the kernel 2019/10/14 11:44:00 setuid sandbox: enabled 2019/10/14 11:44:00 namespace sandbox: enabled 2019/10/14 11:44:00 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/14 11:44:00 fault injection: enabled 2019/10/14 11:44:00 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/14 11:44:00 net packet injection: enabled 2019/10/14 11:44:00 net device setup: enabled 2019/10/14 11:44:00 concurrency sanitizer: enabled syzkaller login: [ 45.759752][ T7167] ================================================================== [ 45.767899][ T7167] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 45.775416][ T7167] [ 45.777734][ T7167] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 0: [ 45.785259][ T7167] __zone_watermark_ok+0x106/0x240 [ 45.790368][ T7167] get_page_from_freelist+0x629/0x2300 [ 45.795810][ T7167] __alloc_pages_nodemask+0x255/0x4d0 [ 45.801165][ T7167] alloc_pages_current+0xd1/0x170 [ 45.806176][ T7167] skb_page_frag_refill+0x16f/0x260 [ 45.811359][ T7167] try_fill_recv+0x51f/0xdc0 [ 45.815929][ T7167] virtnet_poll+0x64c/0x7d0 [ 45.820414][ T7167] net_rx_action+0x3ae/0xa50 [ 45.824987][ T7167] __do_softirq+0x115/0x33f [ 45.829471][ T7167] run_ksoftirqd+0x46/0x60 [ 45.833869][ T7167] smpboot_thread_fn+0x37d/0x4a0 [ 45.838787][ T7167] kthread+0x1d4/0x200 [ 45.842838][ T7167] ret_from_fork+0x1f/0x30 [ 45.847229][ T7167] [ 45.849554][ T7167] write to 0xffff88812fffcf58 of 8 bytes by task 7167 on cpu 1: [ 45.857164][ T7167] free_one_page+0x783/0x840 [ 45.862167][ T7167] __free_pages_ok+0x370/0x640 [ 45.866916][ T7167] free_compound_page+0x3d/0x50 [ 45.871747][ T7167] __put_compound_page+0x4e/0x70 [ 45.876675][ T7167] __put_page+0x54/0xd0 [ 45.880818][ T7167] skb_release_data+0x1ba/0x3a0 [ 45.885648][ T7167] skb_release_all+0x44/0x60 [ 45.890218][ T7167] __kfree_skb+0x1f/0x30 [ 45.894441][ T7167] tcp_recvmsg+0xf59/0x1a30 [ 45.898928][ T7167] inet_recvmsg+0xbb/0x250 [ 45.903324][ T7167] sock_recvmsg+0x92/0xb0 [ 45.907648][ T7167] sock_read_iter+0x15f/0x1e0 [ 45.912308][ T7167] new_sync_read+0x389/0x4f0 [ 45.916871][ T7167] [ 45.919189][ T7167] Reported by Kernel Concurrency Sanitizer on: [ 45.925328][ T7167] CPU: 1 PID: 7167 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 45.932412][ T7167] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.942443][ T7167] ================================================================== [ 45.950483][ T7167] Kernel panic - not syncing: panic_on_warn set ... [ 45.957053][ T7167] CPU: 1 PID: 7167 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 45.964135][ T7167] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 45.974170][ T7167] Call Trace: [ 45.977446][ T7167] dump_stack+0xf5/0x159 [ 45.981688][ T7167] panic+0x209/0x639 [ 45.985567][ T7167] ? tcp_recvmsg+0xf59/0x1a30 [ 45.990226][ T7167] ? vprintk_func+0x8d/0x140 [ 45.994805][ T7167] kcsan_report.cold+0xc/0x1b [ 45.999471][ T7167] __kcsan_setup_watchpoint+0x3ee/0x510 [ 46.005001][ T7167] __tsan_write8+0x32/0x40 [ 46.009401][ T7167] free_one_page+0x783/0x840 [ 46.013985][ T7167] __free_pages_ok+0x370/0x640 [ 46.018737][ T7167] free_compound_page+0x3d/0x50 [ 46.023579][ T7167] __put_compound_page+0x4e/0x70 [ 46.028499][ T7167] __put_page+0x54/0xd0 [ 46.032640][ T7167] skb_release_data+0x1ba/0x3a0 [ 46.037478][ T7167] skb_release_all+0x44/0x60 [ 46.042058][ T7167] __kfree_skb+0x1f/0x30 [ 46.046292][ T7167] tcp_recvmsg+0xf59/0x1a30 [ 46.050792][ T7167] inet_recvmsg+0xbb/0x250 [ 46.055197][ T7167] ? __tsan_read8+0x2c/0x30 [ 46.059688][ T7167] ? inet_sendpage+0x100/0x100 [ 46.064434][ T7167] sock_recvmsg+0x92/0xb0 [ 46.068745][ T7167] sock_read_iter+0x15f/0x1e0 [ 46.073414][ T7167] new_sync_read+0x389/0x4f0 [ 46.077995][ T7167] __vfs_read+0xb1/0xc0 [ 46.082145][ T7167] vfs_read+0x143/0x2c0 [ 46.086289][ T7167] ksys_read+0xd5/0x1b0 [ 46.090433][ T7167] __x64_sys_read+0x4c/0x60 [ 46.094925][ T7167] do_syscall_64+0xcf/0x2f0 [ 46.099423][ T7167] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 46.105296][ T7167] RIP: 0033:0x47c530 [ 46.109180][ T7167] 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 [ 46.128763][ T7167] RSP: 002b:000000c4202c17d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 46.137169][ T7167] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 46.145131][ T7167] RDX: 0000000000001000 RSI: 000000c4202da000 RDI: 0000000000000003 [ 46.153082][ T7167] RBP: 000000c4202c1830 R08: 0000000000000000 R09: 0000000000000000 [ 46.161031][ T7167] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000008 [ 46.168986][ T7167] R13: ffffffffffffffff R14: 0000000000000008 R15: ffffffffffffffff [ 47.305952][ T7167] Shutting down cpus with NMI [ 47.311370][ T7167] Kernel Offset: disabled [ 47.315689][ T7167] Rebooting in 86400 seconds..