[....] Starting enhanced syslogd: rsyslogd[?25l[?1c7[ ok 8[?25h[?0c. [ 76.454307][ T32] audit: type=1800 audit(1570627248.513:25): pid=11389 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="cron" dev="sda1" ino=2414 res=0 [ 76.477648][ T32] audit: type=1800 audit(1570627248.533:26): pid=11389 uid=0 auid=4294967295 ses=4294967295 subj==unconfined op=collect_data cause=failed(directio) comm="startpar" name="mcstrans" dev="sda1" ino=2457 res=0 [ 76.503766][ T32] audit: type=1800 audit(1570627248.563:27): pid=11389 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 '10.128.0.100' (ECDSA) to the list of known hosts. 2019/10/09 13:21:01 fuzzer started 2019/10/09 13:21:05 dialing manager at 10.128.0.26:39087 2019/10/09 13:21:06 syscalls: 2412 2019/10/09 13:21:06 code coverage: enabled 2019/10/09 13:21:06 comparison tracing: CONFIG_KCOV_ENABLE_COMPARISONS is not enabled 2019/10/09 13:21:06 extra coverage: enabled 2019/10/09 13:21:06 setuid sandbox: enabled 2019/10/09 13:21:06 namespace sandbox: enabled 2019/10/09 13:21:06 Android sandbox: /sys/fs/selinux/policy does not exist 2019/10/09 13:21:06 fault injection: enabled 2019/10/09 13:21:06 leak checking: CONFIG_DEBUG_KMEMLEAK is not enabled 2019/10/09 13:21:06 net packet injection: enabled 2019/10/09 13:21:06 net device setup: enabled 2019/10/09 13:21:06 concurrency sanitizer: /sys/kernel/debug/kcsan does not exist syzkaller login: [ 107.415435][T11550] ===================================================== [ 107.422472][T11550] BUG: KMSAN: use-after-free in kfree_skb+0x473/0x4c0 [ 107.429284][T11550] CPU: 0 PID: 11550 Comm: syz-fuzzer Not tainted 5.4.0-rc2+ #0 [ 107.436835][T11550] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 107.446871][T11550] Call Trace: [ 107.450501][T11550] dump_stack+0x191/0x1f0 [ 107.454813][T11550] kmsan_report+0x17d/0x2f0 [ 107.459316][T11550] __msan_warning+0x73/0xe0 [ 107.463816][T11550] kmem_cache_free+0x3df/0x2b70 [ 107.468651][T11550] ? kmsan_internal_set_origin+0x6a/0xb0 [ 107.474263][T11550] ? kfree_skb+0x473/0x4c0 [ 107.478670][T11550] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 107.484732][T11550] kfree_skb+0x473/0x4c0 [ 107.488958][T11550] ? packet_rcv_spkt+0x68d/0x7c0 [ 107.493874][T11550] packet_rcv_spkt+0x68d/0x7c0 [ 107.498636][T11550] ? packet_rcv+0x2110/0x2110 [ 107.503308][T11550] dev_queue_xmit_nit+0x1125/0x1200 [ 107.508512][T11550] dev_hard_start_xmit+0x21e/0xab0 [ 107.513611][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 107.519483][T11550] sch_direct_xmit+0x56c/0x18c0 [ 107.524341][T11550] __dev_queue_xmit+0x212d/0x4200 [ 107.529358][T11550] dev_queue_xmit+0x4b/0x60 [ 107.533841][T11550] ip_finish_output2+0x20d6/0x25d0 [ 107.538937][T11550] ? __msan_metadata_ptr_for_load_2+0x10/0x20 [ 107.544994][T11550] ? nf_ct_deliver_cached_events+0x4d5/0x6e0 [ 107.550967][T11550] __ip_finish_output+0xaf8/0xda0 [ 107.555980][T11550] ip_finish_output+0x2db/0x420 [ 107.560816][T11550] ip_output+0x541/0x610 [ 107.565063][T11550] ? ip_mc_finish_output+0x6d0/0x6d0 [ 107.570334][T11550] ? ip_finish_output+0x420/0x420 [ 107.575346][T11550] __ip_queue_xmit+0x1caf/0x21f0 [ 107.580369][T11550] ? __msan_metadata_ptr_for_store_8+0x13/0x20 [ 107.587725][T11550] ? should_fail+0x1d2/0xa50 [ 107.593489][T11550] ip_queue_xmit+0xcc/0xf0 [ 107.597990][T11550] ? tcp_v4_inbound_md5_hash+0xd10/0xd10 [ 107.603614][T11550] __tcp_transmit_skb+0x40e3/0x5d90 [ 107.608816][T11550] __tcp_send_ack+0x701/0x840 [ 107.613497][T11550] tcp_send_ack+0x68/0x90 [ 107.617828][T11550] tcp_cleanup_rbuf+0x764/0x800 [ 107.622683][T11550] tcp_recvmsg+0x334d/0x4ff0 [ 107.627385][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 107.633369][T11550] ? tcp_mmap+0x150/0x150 [ 107.637952][T11550] ? tcp_mmap+0x150/0x150 [ 107.642455][T11550] inet_recvmsg+0x237/0x7d0 [ 107.647040][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 107.653287][T11550] ? inet_sendpage+0x2c0/0x2c0 [ 107.658127][T11550] ? inet_sendpage+0x2c0/0x2c0 [ 107.662976][T11550] sock_read_iter+0x5be/0x660 [ 107.668014][T11550] ? kernel_sock_ip_overhead+0x340/0x340 [ 107.673650][T11550] __vfs_read+0xa67/0xc90 [ 107.678312][T11550] vfs_read+0x359/0x6f0 [ 107.682943][T11550] ksys_read+0x265/0x430 [ 107.687305][T11550] __se_sys_read+0x92/0xb0 [ 107.691839][T11550] __x64_sys_read+0x4a/0x70 [ 107.696355][T11550] do_syscall_64+0xb6/0x160 [ 107.700844][T11550] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 107.706715][T11550] RIP: 0033:0x47fd44 [ 107.710592][T11550] Code: ff ff cc cc cc cc e8 9b 40 fb ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 45 31 d2 45 31 c0 45 31 c9 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 [ 107.730287][T11550] RSP: 002b:000000c4200657a0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 107.738710][T11550] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047fd44 [ 107.746663][T11550] RDX: 0000000000001000 RSI: 000000c420384000 RDI: 0000000000000003 [ 107.754628][T11550] RBP: 000000c4200657f0 R08: 0000000000000000 R09: 0000000000000000 [ 107.762578][T11550] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000010 [ 107.770538][T11550] R13: 0000000000000010 R14: 0000000000000002 R15: ffffffffffffffff [ 107.778505][T11550] [ 107.780816][T11550] Uninit was stored to memory at: [ 107.785824][T11550] kmsan_internal_chain_origin+0xde/0x190 [ 107.791537][T11550] __msan_chain_origin+0x6b/0xe0 [ 107.796460][T11550] ___slab_alloc+0x1dbc/0x1fb0 [ 107.801208][T11550] kmem_cache_alloc+0xade/0xd10 [ 107.806040][T11550] skb_clone+0x326/0x5d0 [ 107.810258][T11550] dev_queue_xmit_nit+0x539/0x1200 [ 107.815347][T11550] dev_hard_start_xmit+0x21e/0xab0 [ 107.820441][T11550] sch_direct_xmit+0x56c/0x18c0 [ 107.825266][T11550] __dev_queue_xmit+0x212d/0x4200 [ 107.830267][T11550] dev_queue_xmit+0x4b/0x60 [ 107.834752][T11550] ip_finish_output2+0x20d6/0x25d0 [ 107.839852][T11550] __ip_finish_output+0xaf8/0xda0 [ 107.844857][T11550] ip_finish_output+0x2db/0x420 [ 107.849685][T11550] ip_output+0x541/0x610 [ 107.853902][T11550] __ip_queue_xmit+0x1caf/0x21f0 [ 107.858812][T11550] ip_queue_xmit+0xcc/0xf0 [ 107.863215][T11550] __tcp_transmit_skb+0x40e3/0x5d90 [ 107.868422][T11550] __tcp_send_ack+0x701/0x840 [ 107.873189][T11550] tcp_send_ack+0x68/0x90 [ 107.877497][T11550] tcp_cleanup_rbuf+0x764/0x800 [ 107.882345][T11550] tcp_recvmsg+0x334d/0x4ff0 [ 107.886984][T11550] inet_recvmsg+0x237/0x7d0 [ 107.891695][T11550] sock_read_iter+0x5be/0x660 [ 107.896462][T11550] __vfs_read+0xa67/0xc90 [ 107.901031][T11550] vfs_read+0x359/0x6f0 [ 107.905165][T11550] ksys_read+0x265/0x430 [ 107.909508][T11550] __se_sys_read+0x92/0xb0 [ 107.913904][T11550] __x64_sys_read+0x4a/0x70 [ 107.918384][T11550] do_syscall_64+0xb6/0x160 [ 107.922865][T11550] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 107.928734][T11550] [ 107.931054][T11550] Uninit was created at: [ 107.935290][T11550] kmsan_internal_poison_shadow+0x60/0x120 [ 107.941102][T11550] kmsan_slab_free+0x8d/0x100 [ 107.945773][T11550] kmem_cache_free_bulk+0x3ad9/0x3f10 [ 107.951136][T11550] napi_consume_skb+0x593/0x5d0 [ 107.955965][T11550] free_old_xmit_skbs+0x1a1/0x450 [ 107.961260][T11550] virtnet_poll_tx+0x24c/0x4c0 [ 107.966160][T11550] net_rx_action+0x7a6/0x1aa0 [ 107.970961][T11550] __do_softirq+0x4a1/0x83a [ 107.975737][T11550] irq_exit+0x230/0x280 [ 107.979968][T11550] do_IRQ+0x123/0x360 [ 107.983933][T11550] ret_from_intr+0x0/0x33 [ 107.988678][T11550] kmsan_get_shadow_origin_ptr+0x13c/0x4c0 [ 107.994956][T11550] __msan_metadata_ptr_for_load_8+0x10/0x20 [ 108.001021][T11550] vmacache_find+0x2e9/0x700 [ 108.005788][T11550] find_vma+0x7d/0x330 [ 108.010314][T11550] do_user_addr_fault+0x66f/0x1510 [ 108.015404][T11550] __do_page_fault+0x1a2/0x410 [ 108.020252][T11550] do_page_fault+0xbb/0x500 [ 108.024745][T11550] page_fault+0x4e/0x60 [ 108.028872][T11550] ===================================================== [ 108.035878][T11550] Disabling lock debugging due to kernel taint [ 108.042203][T11550] Kernel panic - not syncing: panic_on_warn set ... [ 108.048951][T11550] CPU: 0 PID: 11550 Comm: syz-fuzzer Tainted: G B 5.4.0-rc2+ #0 [ 108.057858][T11550] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 108.067888][T11550] Call Trace: [ 108.071217][T11550] dump_stack+0x191/0x1f0 [ 108.075551][T11550] panic+0x3c9/0xc1e [ 108.080186][T11550] kmsan_report+0x2e5/0x2f0 [ 108.084692][T11550] __msan_warning+0x73/0xe0 [ 108.089284][T11550] kmem_cache_free+0x3df/0x2b70 [ 108.094229][T11550] ? kmsan_internal_set_origin+0x6a/0xb0 [ 108.099863][T11550] ? kfree_skb+0x473/0x4c0 [ 108.104266][T11550] ? kmsan_internal_unpoison_shadow+0x42/0x80 [ 108.110337][T11550] kfree_skb+0x473/0x4c0 [ 108.114573][T11550] ? packet_rcv_spkt+0x68d/0x7c0 [ 108.119504][T11550] packet_rcv_spkt+0x68d/0x7c0 [ 108.124249][T11550] ? packet_rcv+0x2110/0x2110 [ 108.128922][T11550] dev_queue_xmit_nit+0x1125/0x1200 [ 108.134128][T11550] dev_hard_start_xmit+0x21e/0xab0 [ 108.139335][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 108.145235][T11550] sch_direct_xmit+0x56c/0x18c0 [ 108.150091][T11550] __dev_queue_xmit+0x212d/0x4200 [ 108.155109][T11550] dev_queue_xmit+0x4b/0x60 [ 108.159595][T11550] ip_finish_output2+0x20d6/0x25d0 [ 108.164687][T11550] ? __msan_metadata_ptr_for_load_2+0x10/0x20 [ 108.170732][T11550] ? nf_ct_deliver_cached_events+0x4d5/0x6e0 [ 108.176702][T11550] __ip_finish_output+0xaf8/0xda0 [ 108.181737][T11550] ip_finish_output+0x2db/0x420 [ 108.186670][T11550] ip_output+0x541/0x610 [ 108.190932][T11550] ? ip_mc_finish_output+0x6d0/0x6d0 [ 108.196220][T11550] ? ip_finish_output+0x420/0x420 [ 108.202547][T11550] __ip_queue_xmit+0x1caf/0x21f0 [ 108.210052][T11550] ? __msan_metadata_ptr_for_store_8+0x13/0x20 [ 108.216309][T11550] ? should_fail+0x1d2/0xa50 [ 108.220912][T11550] ip_queue_xmit+0xcc/0xf0 [ 108.225310][T11550] ? tcp_v4_inbound_md5_hash+0xd10/0xd10 [ 108.230922][T11550] __tcp_transmit_skb+0x40e3/0x5d90 [ 108.236118][T11550] __tcp_send_ack+0x701/0x840 [ 108.240798][T11550] tcp_send_ack+0x68/0x90 [ 108.245214][T11550] tcp_cleanup_rbuf+0x764/0x800 [ 108.250073][T11550] tcp_recvmsg+0x334d/0x4ff0 [ 108.254756][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 108.261936][T11550] ? tcp_mmap+0x150/0x150 [ 108.266241][T11550] ? tcp_mmap+0x150/0x150 [ 108.270747][T11550] inet_recvmsg+0x237/0x7d0 [ 108.275234][T11550] ? kmsan_get_shadow_origin_ptr+0x6e/0x4c0 [ 108.281299][T11550] ? inet_sendpage+0x2c0/0x2c0 [ 108.286125][T11550] ? inet_sendpage+0x2c0/0x2c0 [ 108.291119][T11550] sock_read_iter+0x5be/0x660 [ 108.295820][T11550] ? kernel_sock_ip_overhead+0x340/0x340 [ 108.302386][T11550] __vfs_read+0xa67/0xc90 [ 108.306733][T11550] vfs_read+0x359/0x6f0 [ 108.312545][T11550] ksys_read+0x265/0x430 [ 108.318248][T11550] __se_sys_read+0x92/0xb0 [ 108.322661][T11550] __x64_sys_read+0x4a/0x70 [ 108.327154][T11550] do_syscall_64+0xb6/0x160 [ 108.331641][T11550] entry_SYSCALL_64_after_hwframe+0x63/0xe7 [ 108.337510][T11550] RIP: 0033:0x47fd44 [ 108.341384][T11550] Code: ff ff cc cc cc cc e8 9b 40 fb ff 48 8b 7c 24 10 48 8b 74 24 18 48 8b 54 24 20 45 31 d2 45 31 c0 45 31 c9 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 [ 108.360965][T11550] RSP: 002b:000000c4200657a0 EFLAGS: 00000246 ORIG_RAX: 0000000000000000 [ 108.369369][T11550] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000047fd44 [ 108.377319][T11550] RDX: 0000000000001000 RSI: 000000c420384000 RDI: 0000000000000003 [ 108.385278][T11550] RBP: 000000c4200657f0 R08: 0000000000000000 R09: 0000000000000000 [ 108.393247][T11550] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000010 [ 108.401196][T11550] R13: 0000000000000010 R14: 0000000000000002 R15: ffffffffffffffff [ 108.411406][T11550] Kernel Offset: disabled [ 108.416610][T11550] Rebooting in 86400 seconds..