[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 81.679335][ T30] audit: type=1800 audit(1572499586.730:25): pid=11787 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 81.702700][ T30] audit: type=1800 audit(1572499586.750:26): pid=11787 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 81.760220][ T30] audit: type=1800 audit(1572499586.790:27): pid=11787 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 '10.128.0.63' (ECDSA) to the list of known hosts. 2019/10/31 05:26:39 fuzzer started 2019/10/31 05:26:44 dialing manager at 10.128.0.26:40999 2019/10/31 05:26:44 syscalls: 2431 2019/10/31 05:26:44 code coverage: enabled 2019/10/31 05:26:44 comparison tracing: CONFIG_KCOV_ENABLE_COMPARISONS is not enabled 2019/10/31 05:26:44 extra coverage: enabled 2019/10/31 05:26:44 setuid sandbox: enabled 2019/10/31 05:26:44 namespace sandbox: enabled 2019/10/31 05:26:44 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/31 05:26:44 fault injection: enabled 2019/10/31 05:26:44 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/31 05:26:44 net packet injection: enabled 2019/10/31 05:26:44 net device setup: enabled 2019/10/31 05:26:44 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 207.807835][ C1] ===================================================== [ 207.815016][ C1] BUG: KMSAN: use-after-free in kmem_cache_free+0x3df/0x2b70 [ 207.822408][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Not tainted 5.4.0-rc5+ #0 [ 207.829782][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 207.839848][ C1] Call Trace: [ 207.843162][ C1] dump_stack+0x191/0x1f0 [ 207.847518][ C1] kmsan_report+0x128/0x220 [ 207.852042][ C1] __msan_warning+0x73/0xe0 [ 207.856560][ C1] kmem_cache_free+0x3df/0x2b70 [ 207.861427][ C1] ? kmsan_internal_set_origin+0x6a/0xb0 [ 207.867177][ C1] ? kfree_skb+0x473/0x4c0 [ 207.871607][ C1] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 207.877847][ C1] kfree_skb+0x473/0x4c0 [ 207.882104][ C1] ? packet_rcv_spkt+0x68d/0x7c0 [ 207.887059][ C1] packet_rcv_spkt+0x68d/0x7c0 [ 207.891846][ C1] ? packet_rcv+0x2110/0x2110 [ 207.896565][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 207.902344][ C1] ? kmsan_get_shadow_origin_ptr+0x91/0x4b0 [ 207.908254][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 207.914003][ C1] napi_gro_receive+0x67f/0xbb0 [ 207.918887][ C1] receive_buf+0x653b/0x8810 [ 207.923621][ C1] ? kmsan_get_shadow_origin_ptr+0x91/0x4b0 [ 207.929673][ C1] virtnet_poll+0x666/0x1a10 [ 207.934432][ C1] ? refill_work+0x470/0x470 [ 207.939030][ C1] net_rx_action+0x7a6/0x1aa0 [ 207.943730][ C1] ? net_tx_action+0xc40/0xc40 [ 207.948505][ C1] __do_softirq+0x4a1/0x83a [ 207.953054][ C1] ? ksoftirqd_should_run+0x30/0x30 [ 207.958260][ C1] ? takeover_tasklets+0x900/0x900 [ 207.963530][ C1] run_ksoftirqd+0x25/0x40 [ 207.967966][ C1] smpboot_thread_fn+0x4a3/0x990 [ 207.973139][ C1] kthread+0x4b5/0x4f0 [ 207.977234][ C1] ? cpu_report_death+0x190/0x190 [ 207.982275][ C1] ? kthread_blkcg+0xf0/0xf0 [ 207.986998][ C1] ret_from_fork+0x35/0x40 [ 207.991424][ C1] [ 207.993753][ C1] Uninit was stored to memory at: [ 207.998788][ C1] kmsan_internal_chain_origin+0xbd/0x180 [ 208.004515][ C1] __msan_chain_origin+0x6b/0xd0 [ 208.009455][ C1] ___slab_alloc+0x1dbc/0x1fb0 [ 208.014223][ C1] kmem_cache_alloc+0xadf/0xd20 [ 208.019078][ C1] skb_clone+0x326/0x5d0 [ 208.023332][ C1] packet_rcv_spkt+0x23f/0x7c0 [ 208.028218][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 208.033951][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 208.039670][ C1] napi_gro_receive+0x67f/0xbb0 [ 208.044736][ C1] receive_buf+0x653b/0x8810 [ 208.049543][ C1] virtnet_poll+0x666/0x1a10 [ 208.054126][ C1] net_rx_action+0x7a6/0x1aa0 [ 208.058885][ C1] __do_softirq+0x4a1/0x83a [ 208.063383][ C1] run_ksoftirqd+0x25/0x40 [ 208.067908][ C1] smpboot_thread_fn+0x4a3/0x990 [ 208.072961][ C1] kthread+0x4b5/0x4f0 [ 208.077014][ C1] ret_from_fork+0x35/0x40 [ 208.081410][ C1] [ 208.083978][ C1] Uninit was created at: [ 208.088212][ C1] kmsan_internal_poison_shadow+0x60/0x120 [ 208.094039][ C1] kmsan_slab_free+0x8d/0xf0 [ 208.098611][ C1] kmem_cache_free_bulk+0x3ad9/0x3f10 [ 208.103968][ C1] __kfree_skb_flush+0xb0/0x100 [ 208.108804][ C1] net_rx_action+0x1a5e/0x1aa0 [ 208.113553][ C1] __do_softirq+0x4a1/0x83a [ 208.118047][ C1] run_ksoftirqd+0x25/0x40 [ 208.122445][ C1] smpboot_thread_fn+0x4a3/0x990 [ 208.127371][ C1] kthread+0x4b5/0x4f0 [ 208.131485][ C1] ret_from_fork+0x35/0x40 [ 208.135882][ C1] ===================================================== [ 208.142800][ C1] Disabling lock debugging due to kernel taint [ 208.148940][ C1] Kernel panic - not syncing: panic_on_warn set ... [ 208.155515][ C1] CPU: 1 PID: 16 Comm: ksoftirqd/1 Tainted: G B 5.4.0-rc5+ #0 [ 208.164775][ C1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 208.174817][ C1] Call Trace: [ 208.178101][ C1] dump_stack+0x191/0x1f0 [ 208.182419][ C1] panic+0x3c9/0xc1e [ 208.186322][ C1] kmsan_report+0x215/0x220 [ 208.191053][ C1] __msan_warning+0x73/0xe0 [ 208.195770][ C1] kmem_cache_free+0x3df/0x2b70 [ 208.200868][ C1] ? kmsan_internal_set_origin+0x6a/0xb0 [ 208.206645][ C1] ? kfree_skb+0x473/0x4c0 [ 208.211237][ C1] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 208.217417][ C1] kfree_skb+0x473/0x4c0 [ 208.221691][ C1] ? packet_rcv_spkt+0x68d/0x7c0 [ 208.226715][ C1] packet_rcv_spkt+0x68d/0x7c0 [ 208.231469][ C1] ? packet_rcv+0x2110/0x2110 [ 208.236184][ C1] __netif_receive_skb_core+0x3aed/0x51a0 [ 208.241941][ C1] ? kmsan_get_shadow_origin_ptr+0x91/0x4b0 [ 208.247825][ C1] netif_receive_skb_internal+0x3cc/0xc20 [ 208.253538][ C1] napi_gro_receive+0x67f/0xbb0 [ 208.258382][ C1] receive_buf+0x653b/0x8810 [ 208.263022][ C1] ? kmsan_get_shadow_origin_ptr+0x91/0x4b0 [ 208.268904][ C1] virtnet_poll+0x666/0x1a10 [ 208.273624][ C1] ? refill_work+0x470/0x470 [ 208.278294][ C1] net_rx_action+0x7a6/0x1aa0 [ 208.282969][ C1] ? net_tx_action+0xc40/0xc40 [ 208.287719][ C1] __do_softirq+0x4a1/0x83a [ 208.292212][ C1] ? ksoftirqd_should_run+0x30/0x30 [ 208.297397][ C1] ? takeover_tasklets+0x900/0x900 [ 208.302496][ C1] run_ksoftirqd+0x25/0x40 [ 208.306908][ C1] smpboot_thread_fn+0x4a3/0x990 [ 208.311838][ C1] kthread+0x4b5/0x4f0 [ 208.315896][ C1] ? cpu_report_death+0x190/0x190 [ 208.320941][ C1] ? kthread_blkcg+0xf0/0xf0 [ 208.325547][ C1] ret_from_fork+0x35/0x40 [ 208.331858][ C1] Kernel Offset: disabled [ 208.336192][ C1] Rebooting in 86400 seconds..