[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 36.749505][ T26] audit: type=1800 audit(1570955286.593:25): pid=7106 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2447 res=0 [ 36.791793][ T26] audit: type=1800 audit(1570955286.593:26): pid=7106 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2490 res=0 [ 36.826571][ T26] audit: type=1800 audit(1570955286.593:27): pid=7106 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 '10.128.0.169' (ECDSA) to the list of known hosts. 2019/10/13 08:28:17 fuzzer started 2019/10/13 08:28:18 dialing manager at 10.128.0.105:43913 2019/10/13 08:28:18 syscalls: 2523 2019/10/13 08:28:18 code coverage: enabled 2019/10/13 08:28:18 comparison tracing: enabled 2019/10/13 08:28:18 extra coverage: extra coverage is not supported by the kernel 2019/10/13 08:28:18 setuid sandbox: enabled 2019/10/13 08:28:18 namespace sandbox: enabled 2019/10/13 08:28:18 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/13 08:28:18 fault injection: enabled 2019/10/13 08:28:18 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/13 08:28:18 net packet injection: enabled 2019/10/13 08:28:18 net device setup: enabled 2019/10/13 08:28:18 concurrency sanitizer: enabled syzkaller login: [ 49.221674][ T7271] ================================================================== [ 49.229795][ T7271] BUG: KCSAN: data-race in __zone_watermark_ok / free_one_page [ 49.237311][ T7271] [ 49.239628][ T7271] read to 0xffff88812fffcf58 of 8 bytes by interrupt on cpu 1: [ 49.247161][ T7271] __zone_watermark_ok+0x106/0x240 [ 49.252256][ T7271] get_page_from_freelist+0x629/0x2300 [ 49.257698][ T7271] __alloc_pages_nodemask+0x255/0x4d0 [ 49.263056][ T7271] page_frag_alloc+0x11e/0x2d0 [ 49.267817][ T7271] __napi_alloc_skb+0x172/0x210 [ 49.272652][ T7271] page_to_skb+0x8d/0x480 [ 49.276968][ T7271] receive_buf+0x17c7/0x30b0 [ 49.282516][ T7271] virtnet_poll+0x436/0x7d0 [ 49.287001][ T7271] net_rx_action+0x3ae/0xa50 [ 49.291574][ T7271] __do_softirq+0x115/0x33f [ 49.296061][ T7271] run_ksoftirqd+0x46/0x60 [ 49.300464][ T7271] smpboot_thread_fn+0x37d/0x4a0 [ 49.305539][ T7271] kthread+0x1d4/0x200 [ 49.309590][ T7271] ret_from_fork+0x1f/0x30 [ 49.313991][ T7271] [ 49.316306][ T7271] write to 0xffff88812fffcf58 of 8 bytes by task 7271 on cpu 0: [ 49.323915][ T7271] free_one_page+0x783/0x840 [ 49.328492][ T7271] __free_pages_ok+0x370/0x640 [ 49.333245][ T7271] free_compound_page+0x3d/0x50 [ 49.338079][ T7271] __put_compound_page+0x4e/0x70 [ 49.342997][ T7271] __put_page+0x54/0xd0 [ 49.347140][ T7271] skb_release_data+0x1ba/0x3a0 [ 49.351972][ T7271] skb_release_all+0x44/0x60 [ 49.356717][ T7271] __kfree_skb+0x1f/0x30 [ 49.361075][ T7271] tcp_recvmsg+0xf59/0x1a30 [ 49.365562][ T7271] inet_recvmsg+0xbb/0x250 [ 49.369959][ T7271] sock_recvmsg+0x92/0xb0 [ 49.374272][ T7271] sock_read_iter+0x15f/0x1e0 [ 49.378935][ T7271] new_sync_read+0x389/0x4f0 [ 49.383498][ T7271] [ 49.385806][ T7271] Reported by Kernel Concurrency Sanitizer on: [ 49.391945][ T7271] CPU: 0 PID: 7271 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.399029][ T7271] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.409201][ T7271] ================================================================== [ 49.417272][ T7271] Kernel panic - not syncing: panic_on_warn set ... [ 49.423852][ T7271] CPU: 0 PID: 7271 Comm: syz-fuzzer Not tainted 5.3.0+ #0 [ 49.430954][ T7271] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 49.440991][ T7271] Call Trace: [ 49.444272][ T7271] dump_stack+0xf5/0x159 [ 49.448504][ T7271] panic+0x209/0x639 [ 49.452386][ T7271] ? tcp_recvmsg+0xf59/0x1a30 [ 49.457047][ T7271] ? vprintk_func+0x8d/0x140 [ 49.461628][ T7271] kcsan_report.cold+0xc/0x1b [ 49.466311][ T7271] __kcsan_setup_watchpoint+0x3ee/0x510 [ 49.472801][ T7271] __tsan_write8+0x32/0x40 [ 49.477326][ T7271] free_one_page+0x783/0x840 [ 49.482530][ T7271] __free_pages_ok+0x370/0x640 [ 49.487297][ T7271] free_compound_page+0x3d/0x50 [ 49.492133][ T7271] __put_compound_page+0x4e/0x70 [ 49.497054][ T7271] __put_page+0x54/0xd0 [ 49.501198][ T7271] skb_release_data+0x1ba/0x3a0 [ 49.506036][ T7271] skb_release_all+0x44/0x60 [ 49.510720][ T7271] __kfree_skb+0x1f/0x30 [ 49.514950][ T7271] tcp_recvmsg+0xf59/0x1a30 [ 49.519461][ T7271] ? debug_smp_processor_id+0x4c/0x172 [ 49.524911][ T7271] inet_recvmsg+0xbb/0x250 [ 49.529311][ T7271] ? __tsan_read8+0x2c/0x30 [ 49.533821][ T7271] ? inet_sendpage+0x100/0x100 [ 49.538581][ T7271] sock_recvmsg+0x92/0xb0 [ 49.542904][ T7271] sock_read_iter+0x15f/0x1e0 [ 49.547585][ T7271] new_sync_read+0x389/0x4f0 [ 49.552175][ T7271] __vfs_read+0xb1/0xc0 [ 49.556321][ T7271] vfs_read+0x143/0x2c0 [ 49.560470][ T7271] ksys_read+0xd5/0x1b0 [ 49.564631][ T7271] __x64_sys_read+0x4c/0x60 [ 49.569124][ T7271] do_syscall_64+0xcf/0x2f0 [ 49.573619][ T7271] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 49.579594][ T7271] RIP: 0033:0x47c530 [ 49.583488][ T7271] 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 [ 49.603083][ T7271] RSP: 002b:000000c42032d7d8 EFLAGS: 00000212 ORIG_RAX: 0000000000000000 [ 49.611481][ T7271] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047c530 [ 49.619438][ T7271] RDX: 0000000000001000 RSI: 000000c4200cc000 RDI: 0000000000000003 [ 49.627401][ T7271] RBP: 000000c42032d830 R08: 0000000000000000 R09: 0000000000000000 [ 49.635365][ T7271] R10: 0000000000000000 R11: 0000000000000212 R12: 0000000000000010 [ 49.643327][ T7271] R13: ffffffffffffffff R14: 0000000000000002 R15: ffffffffffffffff [ 50.780777][ T7271] Shutting down cpus with NMI [ 50.786867][ T7271] Kernel Offset: disabled [ 50.791234][ T7271] Rebooting in 86400 seconds..