[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 37.344511][ T26] audit: type=1800 audit(1570897416.277:25): pid=7079 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 37.371952][ T26] audit: type=1800 audit(1570897416.277:26): pid=7079 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 37.407325][ T26] audit: type=1800 audit(1570897416.277:27): pid=7079 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 '10.128.0.209' (ECDSA) to the list of known hosts. 2019/10/12 16:23:46 fuzzer started 2019/10/12 16:23:47 dialing manager at 10.128.0.105:43913 2019/10/12 16:23:47 syscalls: 2523 2019/10/12 16:23:47 code coverage: enabled 2019/10/12 16:23:47 comparison tracing: enabled 2019/10/12 16:23:47 extra coverage: extra coverage is not supported by the kernel 2019/10/12 16:23:47 setuid sandbox: enabled 2019/10/12 16:23:47 namespace sandbox: enabled 2019/10/12 16:23:47 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/12 16:23:47 fault injection: enabled 2019/10/12 16:23:47 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/12 16:23:47 net packet injection: enabled 2019/10/12 16:23:47 net device setup: enabled 2019/10/12 16:23:47 concurrency sanitizer: enabled syzkaller login: [ 50.244168][ T7240] ================================================================== [ 50.252305][ T7240] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 50.259824][ T7240] [ 50.262157][ T7240] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1: [ 50.269689][ T7240] __zone_watermark_ok+0x106/0x240 [ 50.274803][ T7240] get_page_from_freelist+0x629/0x2300 [ 50.280248][ T7240] __alloc_pages_nodemask+0x255/0x4d0 [ 50.285602][ T7240] alloc_pages_current+0xd1/0x170 [ 50.290632][ T7240] skb_page_frag_refill+0x16f/0x260 [ 50.295834][ T7240] try_fill_recv+0x51f/0xdc0 [ 50.300410][ T7240] virtnet_poll+0x64c/0x7d0 [ 50.304909][ T7240] net_rx_action+0x3ae/0xa50 [ 50.309488][ T7240] __do_softirq+0x115/0x33f [ 50.313976][ T7240] run_ksoftirqd+0x46/0x60 [ 50.318375][ T7240] smpboot_thread_fn+0x37d/0x4a0 [ 50.323336][ T7240] kthread+0x1d4/0x200 [ 50.327396][ T7240] ret_from_fork+0x1f/0x30 [ 50.331790][ T7240] [ 50.334106][ T7240] write to 0xffff88812fffcf58 of 8 bytes by task 7240 on cpu 0: [ 50.341738][ T7240] free_one_page+0x214/0x840 [ 50.346326][ T7240] __free_pages_ok+0x370/0x640 [ 50.351078][ T7240] free_compound_page+0x3d/0x50 [ 50.355914][ T7240] __put_compound_page+0x4e/0x70 [ 50.360835][ T7240] __put_page+0x54/0xd0 [ 50.364978][ T7240] skb_release_data+0x1ba/0x3a0 [ 50.369811][ T7240] skb_release_all+0x44/0x60 [ 50.374386][ T7240] __kfree_skb+0x1f/0x30 [ 50.378612][ T7240] tcp_recvmsg+0xf59/0x1a30 [ 50.383101][ T7240] inet_recvmsg+0xbb/0x250 [ 50.387501][ T7240] sock_recvmsg+0x92/0xb0 [ 50.391816][ T7240] sock_read_iter+0x15f/0x1e0 [ 50.396480][ T7240] new_sync_read+0x389/0x4f0 [ 50.401059][ T7240] [ 50.403383][ T7240] Reported by Kernel Concurrency Sanitizer on: [ 50.409524][ T7240] CPU: 0 PID: 7240 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 50.416611][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.426648][ T7240] ================================================================== [ 50.434705][ T7240] Kernel panic - not syncing: panic_on_warn set ... [ 50.441277][ T7240] CPU: 0 PID: 7240 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 50.448376][ T7240] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 50.458413][ T7240] Call Trace: [ 50.461693][ T7240] dump_stack+0xf5/0x159 [ 50.465925][ T7240] panic+0x209/0x639 [ 50.469832][ T7240] ? tcp_recvmsg+0xf59/0x1a30 [ 50.474528][ T7240] ? vprintk_func+0x8d/0x140 [ 50.479141][ T7240] kcsan_report.cold+0xc/0x1b [ 50.483811][ T7240] __kcsan_setup_watchpoint+0x3ee/0x510 [ 50.489355][ T7240] __tsan_write8+0x32/0x40 [ 50.493760][ T7240] free_one_page+0x214/0x840 [ 50.498350][ T7240] __free_pages_ok+0x370/0x640 [ 50.503106][ T7240] free_compound_page+0x3d/0x50 [ 50.507945][ T7240] __put_compound_page+0x4e/0x70 [ 50.512869][ T7240] __put_page+0x54/0xd0 [ 50.517011][ T7240] skb_release_data+0x1ba/0x3a0 [ 50.523500][ T7240] skb_release_all+0x44/0x60 [ 50.528074][ T7240] __kfree_skb+0x1f/0x30 [ 50.532304][ T7240] tcp_recvmsg+0xf59/0x1a30 [ 50.536814][ T7240] inet_recvmsg+0xbb/0x250 [ 50.541216][ T7240] ? __tsan_read8+0x2c/0x30 [ 50.545725][ T7240] ? inet_sendpage+0x100/0x100 [ 50.550479][ T7240] sock_recvmsg+0x92/0xb0 [ 50.554800][ T7240] sock_read_iter+0x15f/0x1e0 [ 50.559472][ T7240] new_sync_read+0x389/0x4f0 [ 50.564061][ T7240] __vfs_read+0xb1/0xc0 [ 50.568205][ T7240] vfs_read+0x143/0x2c0 [ 50.572359][ T7240] ksys_read+0xd5/0x1b0 [ 50.576506][ T7240] __x64_sys_read+0x4c/0x60 [ 50.581002][ T7240] do_syscall_64+0xcf/0x2f0 [ 50.585501][ T7240] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 50.591382][ T7240] RIP: 0033:0x47c530 [ 50.595269][ T7240] 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 [ 50.614872][ T7240] RSP: 002b:000000c4204e3810 EFLAGS: 00000202 ORIG_RAX: 0000000000000000 [ 50.623291][ T7240] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 50.631253][ T7240] RDX: 0000000000001000 RSI: 000000c4201a2000 RDI: 0000000000000003 [ 50.639211][ T7240] RBP: 000000c4204e3868 R08: 0000000000000000 R09: 0000000000000000 [ 50.647166][ T7240] R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000020 [ 50.655122][ T7240] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 51.794457][ T7240] Shutting down cpus with NMI [ 51.800512][ T7240] Kernel Offset: disabled [ 51.804835][ T7240] Rebooting in 86400 seconds..