[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 74.346713][ T32] audit: type=1800 audit(1570540951.390:25): pid=11105 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 74.369712][ T32] audit: type=1800 audit(1570540951.420:26): pid=11105 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 74.412745][ T32] audit: type=1800 audit(1570540951.440:27): pid=11105 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="restorecond" dev="sda1" ino=2436 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 '10.128.1.12' (ECDSA) to the list of known hosts. 2019/10/08 13:22:47 fuzzer started 2019/10/08 13:22:52 dialing manager at 10.128.0.26:39515 2019/10/08 13:22:52 syscalls: 2412 2019/10/08 13:22:52 code coverage: enabled 2019/10/08 13:22:52 comparison tracing: CONFIG_KCOV_ENABLE_COMPARISONS is not enabled 2019/10/08 13:22:52 extra coverage: enabled 2019/10/08 13:22:52 setuid sandbox: enabled 2019/10/08 13:22:52 namespace sandbox: enabled 2019/10/08 13:22:52 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/08 13:22:52 fault injection: enabled 2019/10/08 13:22:52 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/08 13:22:52 net packet injection: enabled 2019/10/08 13:22:52 net device setup: enabled 2019/10/08 13:22:52 concurrency sanitizer: /proc/kcsaninfo does not exist syzkaller login: [ 103.992731][ C1] ===================================================== [ 103.999727][ C1] BUG: KMSAN: use-after-free in kfree_skb+0x473/0x4c0 [ 104.006493][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.3.0-rc7+ #0 [ 104.013864][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 104.024051][ C1] Call Trace: [ 104.027334][ C1] dump_stack+0x191/0x1f0 [ 104.031650][ C1] kmsan_report+0x17d/0x2f0 [ 104.036373][ C1] __msan_warning+0x73/0xe0 [ 104.040860][ C1] kmem_cache_free+0x3df/0x2b70 [ 104.045688][ C1] ? kmsan_internal_set_origin+0x6a/0xb0 [ 104.051296][ C1] ? kfree_skb+0x473/0x4c0 [ 104.055694][ C1] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 104.061749][ C1] kfree_skb+0x473/0x4c0 [ 104.065971][ C1] ? packet_rcv_spkt+0x719/0x840 [ 104.070886][ C1] packet_rcv_spkt+0x719/0x840 [ 104.075638][ C1] ? packet_rcv+0x2190/0x2190 [ 104.080295][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 104.086009][ C1] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 104.091886][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 104.097590][ C1] napi_gro_receive+0x682/0xb90 [ 104.102425][ C1] receive_buf+0x653b/0x8810 [ 104.107029][ C1] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 104.112919][ C1] virtnet_poll+0x666/0x19d0 [ 104.117646][ C1] ? refill_work+0x460/0x460 [ 104.122269][ C1] net_rx_action+0x74b/0x1950 [ 104.126943][ C1] ? net_tx_action+0xba0/0xba0 [ 104.131697][ C1] __do_softirq+0x4a1/0x83a [ 104.136192][ C1] ? ksoftirqd_should_run+0x30/0x30 [ 104.141370][ C1] ? takeover_tasklets+0x900/0x900 [ 104.146456][ C1] run_ksoftirqd+0x25/0x40 [ 104.150906][ C1] smpboot_thread_fn+0x4a3/0x990 [ 104.155833][ C1] kthread+0x4b5/0x4f0 [ 104.159882][ C1] ? cpu_report_death+0x190/0x190 [ 104.164884][ C1] ? kthread_blkcg+0xf0/0xf0 [ 104.169452][ C1] ret_from_fork+0x35/0x40 [ 104.173847][ C1] [ 104.176149][ C1] Uninit was stored to memory at: [ 104.181163][ C1] kmsan_internal_chain_origin+0xde/0x190 [ 104.186857][ C1] __msan_chain_origin+0x6b/0xe0 [ 104.192913][ C1] ___slab_alloc+0x1dbc/0x1fb0 [ 104.197654][ C1] kmem_cache_alloc+0xade/0xd10 [ 104.202479][ C1] skb_clone+0x326/0x5d0 [ 104.206697][ C1] packet_rcv_spkt+0x245/0x840 [ 104.211437][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 104.217134][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 104.222833][ C1] napi_gro_receive+0x682/0xb90 [ 104.227674][ C1] receive_buf+0x653b/0x8810 [ 104.232248][ C1] virtnet_poll+0x666/0x19d0 [ 104.236838][ C1] net_rx_action+0x74b/0x1950 [ 104.241494][ C1] __do_softirq+0x4a1/0x83a [ 104.245976][ C1] run_ksoftirqd+0x25/0x40 [ 104.250385][ C1] smpboot_thread_fn+0x4a3/0x990 [ 104.255303][ C1] kthread+0x4b5/0x4f0 [ 104.259365][ C1] ret_from_fork+0x35/0x40 [ 104.263752][ C1] [ 104.266058][ C1] Uninit was created at: [ 104.270282][ C1] kmsan_internal_poison_shadow+0x60/0x120 [ 104.276085][ C1] kmsan_slab_free+0x8d/0x100 [ 104.280743][ C1] kmem_cache_free_bulk+0x3ad9/0x3f50 [ 104.286093][ C1] __kfree_skb_flush+0xb0/0x100 [ 104.290924][ C1] net_rx_action+0x1908/0x1950 [ 104.295669][ C1] __do_softirq+0x4a1/0x83a [ 104.300150][ C1] irq_exit+0x230/0x280 [ 104.304283][ C1] do_IRQ+0x20d/0x3a0 [ 104.308242][ C1] ret_from_intr+0x0/0x33 [ 104.312550][ C1] default_idle+0x53/0x90 [ 104.316867][ C1] arch_cpu_idle+0x25/0x30 [ 104.321324][ C1] do_idle+0x1d7/0x790 [ 104.325395][ C1] cpu_startup_entry+0x45/0x50 [ 104.330146][ C1] start_secondary+0x370/0x470 [ 104.334895][ C1] secondary_startup_64+0xa4/0xb0 [ 104.339894][ C1] ===================================================== [ 104.347061][ C1] Disabling lock debugging due to kernel taint [ 104.353187][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 104.359751][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Tainted: G B 5.3.0-rc7+ #0 [ 104.368488][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 104.378527][ C1] Call Trace: [ 104.381803][ C1] dump_stack+0x191/0x1f0 [ 104.386125][ C1] panic+0x3c9/0xc1e [ 104.390024][ C1] kmsan_report+0x2e5/0x2f0 [ 104.394522][ C1] __msan_warning+0x73/0xe0 [ 104.399006][ C1] kmem_cache_free+0x3df/0x2b70 [ 104.403834][ C1] ? kmsan_internal_set_origin+0x6a/0xb0 [ 104.409443][ C1] ? kfree_skb+0x473/0x4c0 [ 104.413838][ C1] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 104.419895][ C1] kfree_skb+0x473/0x4c0 [ 104.424119][ C1] ? packet_rcv_spkt+0x719/0x840 [ 104.429036][ C1] packet_rcv_spkt+0x719/0x840 [ 104.433786][ C1] ? packet_rcv+0x2190/0x2190 [ 104.438446][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 104.444160][ C1] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 104.450031][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 104.455751][ C1] napi_gro_receive+0x682/0xb90 [ 104.460585][ C1] receive_buf+0x653b/0x8810 [ 104.465186][ C1] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 104.471185][ C1] virtnet_poll+0x666/0x19d0 [ 104.475779][ C1] ? refill_work+0x460/0x460 [ 104.480365][ C1] net_rx_action+0x74b/0x1950 [ 104.485035][ C1] ? net_tx_action+0xba0/0xba0 [ 104.489788][ C1] __do_softirq+0x4a1/0x83a [ 104.494345][ C1] ? ksoftirqd_should_run+0x30/0x30 [ 104.499683][ C1] ? takeover_tasklets+0x900/0x900 [ 104.504783][ C1] run_ksoftirqd+0x25/0x40 [ 104.509383][ C1] smpboot_thread_fn+0x4a3/0x990 [ 104.514317][ C1] kthread+0x4b5/0x4f0 [ 104.518369][ C1] ? cpu_report_death+0x190/0x190 [ 104.523374][ C1] ? kthread_blkcg+0xf0/0xf0 [ 104.527944][ C1] ret_from_fork+0x35/0x40 [ 104.533710][ C1] Kernel Offset: disabled [ 104.538036][ C1] Rebooting in 86400 seconds..