[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ OK ] Reached target Login Prompts. [ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Update UTMP about System Runlevel Changes. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.113' (ECDSA) to the list of known hosts. 2020/06/19 18:22:24 fuzzer started 2020/06/19 18:22:24 connecting to host at 10.128.0.26:46533 2020/06/19 18:22:24 checking machine... 2020/06/19 18:22:24 checking revisions... 2020/06/19 18:22:24 testing simple program... syzkaller login: [ 61.723010][ T6839] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 18:22:24 building call list... [ 62.074852][ T7] tipc: TX() has been purged, node left! [ 62.597147][ T7] ================================================================== [ 62.605382][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.613296][ T7] Write of size 1 at addr ffff8880a915b1e4 by task kworker/u4:0/7 [ 62.621098][ T7] [ 62.623429][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.631620][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.641687][ T7] Workqueue: netns cleanup_net [ 62.646443][ T7] Call Trace: [ 62.649737][ T7] dump_stack+0x18f/0x20d [ 62.654074][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.659617][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.665159][ T7] ? afs_put_call+0xa40/0xa40 [ 62.669834][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.676862][ T7] ? vprintk_func+0x97/0x1a6 [ 62.681455][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.687003][ T7] kasan_report.cold+0x1f/0x37 [ 62.691886][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.697522][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.703068][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 62.708436][ T7] ? afs_close_socket+0x320/0x320 [ 62.713460][ T7] ? afs_put_call+0xa40/0xa40 [ 62.718138][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 62.723254][ T7] ? afs_put_call+0xa40/0xa40 [ 62.727930][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.734346][ T7] rxrpc_call_completed+0xca/0xf0 [ 62.739387][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 62.744783][ T7] ? lock_sock_nested+0x94/0x110 [ 62.749722][ T7] rxrpc_listen+0x147/0x360 [ 62.754231][ T7] afs_close_socket+0x95/0x320 [ 62.758991][ T7] ? afs_purge_servers+0x16d/0x300 [ 62.764100][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 62.769563][ T7] ? init_wait_var_entry+0x200/0x200 [ 62.774864][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.780515][ T7] ? check_preemption_disabled+0x38/0x220 [ 62.786335][ T7] afs_net_exit+0x1bc/0x310 [ 62.790854][ T7] ? afs_net_init+0xe30/0xe30 [ 62.795537][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.800673][ T7] cleanup_net+0x511/0xa50 [ 62.805090][ T7] ? unregister_pernet_device+0x70/0x70 [ 62.810636][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.816651][ T7] process_one_work+0x965/0x1690 [ 62.821599][ T7] ? lock_release+0x800/0x800 [ 62.826277][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.831652][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 62.836603][ T7] worker_thread+0x96/0xe10 [ 62.841121][ T7] ? process_one_work+0x1690/0x1690 [ 62.846319][ T7] kthread+0x3b5/0x4a0 [ 62.850388][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.856546][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.862267][ T7] ret_from_fork+0x1f/0x30 [ 62.866691][ T7] [ 62.869015][ T7] Allocated by task 6839: [ 62.873362][ T7] save_stack+0x1b/0x40 [ 62.877521][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.883153][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.888523][ T7] afs_alloc_call+0x55/0x630 [ 62.893105][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 62.898661][ T7] afs_open_socket+0x292/0x360 [ 62.903426][ T7] afs_net_init+0xa6c/0xe30 [ 62.907923][ T7] ops_init+0xaf/0x420 [ 62.911983][ T7] setup_net+0x2de/0x860 [ 62.916223][ T7] copy_net_ns+0x293/0x590 [ 62.920696][ T7] create_new_namespaces+0x3fb/0xb30 [ 62.925984][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.931615][ T7] ksys_unshare+0x43d/0x8e0 [ 62.936116][ T7] __x64_sys_unshare+0x2d/0x40 [ 62.940874][ T7] do_syscall_64+0x60/0xe0 [ 62.945294][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.951172][ T7] [ 62.953493][ T7] Freed by task 7: [ 62.957233][ T7] save_stack+0x1b/0x40 [ 62.961385][ T7] __kasan_slab_free+0xf7/0x140 [ 62.966226][ T7] kfree+0x109/0x2b0 [ 62.970115][ T7] afs_put_call+0x585/0xa40 [ 62.974666][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 62.980039][ T7] rxrpc_listen+0x147/0x360 [ 62.984555][ T7] afs_close_socket+0x95/0x320 [ 62.989329][ T7] afs_net_exit+0x1bc/0x310 [ 62.993844][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.998962][ T7] cleanup_net+0x511/0xa50 [ 63.003376][ T7] process_one_work+0x965/0x1690 [ 63.008340][ T7] worker_thread+0x96/0xe10 [ 63.012839][ T7] kthread+0x3b5/0x4a0 [ 63.016910][ T7] ret_from_fork+0x1f/0x30 [ 63.021335][ T7] [ 63.023660][ T7] The buggy address belongs to the object at ffff8880a915b000 [ 63.023660][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 63.037710][ T7] The buggy address is located 484 bytes inside of [ 63.037710][ T7] 1024-byte region [ffff8880a915b000, ffff8880a915b400) [ 63.051323][ T7] The buggy address belongs to the page: [ 63.057042][ T7] page:ffffea0002a456c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 63.066147][ T7] flags: 0xfffe0000000200(slab) [ 63.071021][ T7] raw: 00fffe0000000200 ffffea0002996d08 ffffea00027c2808 ffff8880aa000c40 [ 63.079618][ T7] raw: 0000000000000000 ffff8880a915b000 0000000100000002 0000000000000000 [ 63.088207][ T7] page dumped because: kasan: bad access detected [ 63.094716][ T7] [ 63.097048][ T7] Memory state around the buggy address: [ 63.102689][ T7] ffff8880a915b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.111022][ T7] ffff8880a915b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.119090][ T7] >ffff8880a915b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.127149][ T7] ^ [ 63.134341][ T7] ffff8880a915b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.142400][ T7] ffff8880a915b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.150465][ T7] ================================================================== [ 63.159212][ T7] Disabling lock debugging due to kernel taint [ 63.165396][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 63.171980][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.181506][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.191738][ T7] Workqueue: netns cleanup_net [ 63.196497][ T7] Call Trace: [ 63.199788][ T7] dump_stack+0x18f/0x20d [ 63.204120][ T7] ? afs_wake_up_async_call+0x670/0x770 [ 63.209667][ T7] ? afs_put_call+0xa40/0xa40 [ 63.214346][ T7] panic+0x2e3/0x75c [ 63.218265][ T7] ? __warn_printk+0xf3/0xf3 [ 63.222851][ T7] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.229000][ T7] ? trace_hardirqs_on+0x55/0x220 [ 63.234025][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.239667][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.245287][ T7] ? afs_put_call+0xa40/0xa40 [ 63.249971][ T7] end_report+0x4d/0x53 [ 63.254123][ T7] kasan_report.cold+0xd/0x37 [ 63.258799][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.264423][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.269964][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 63.275338][ T7] ? afs_close_socket+0x320/0x320 [ 63.280352][ T7] ? afs_put_call+0xa40/0xa40 [ 63.285025][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 63.290157][ T7] ? afs_put_call+0xa40/0xa40 [ 63.294831][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.301239][ T7] rxrpc_call_completed+0xca/0xf0 [ 63.306263][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 63.311631][ T7] ? lock_sock_nested+0x94/0x110 [ 63.316565][ T7] rxrpc_listen+0x147/0x360 [ 63.321088][ T7] afs_close_socket+0x95/0x320 [ 63.325844][ T7] ? afs_purge_servers+0x16d/0x300 [ 63.330948][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 63.336404][ T7] ? init_wait_var_entry+0x200/0x200 [ 63.341682][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.347569][ T7] ? check_preemption_disabled+0x38/0x220 [ 63.353305][ T7] afs_net_exit+0x1bc/0x310 [ 63.357801][ T7] ? afs_net_init+0xe30/0xe30 [ 63.362466][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 63.367570][ T7] cleanup_net+0x511/0xa50 [ 63.371994][ T7] ? unregister_pernet_device+0x70/0x70 [ 63.377763][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.383752][ T7] process_one_work+0x965/0x1690 [ 63.388693][ T7] ? lock_release+0x800/0x800 [ 63.393377][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.399799][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 63.404752][ T7] worker_thread+0x96/0xe10 [ 63.409257][ T7] ? process_one_work+0x1690/0x1690 [ 63.414543][ T7] kthread+0x3b5/0x4a0 [ 63.418622][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.424335][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.430062][ T7] ret_from_fork+0x1f/0x30 [ 63.436134][ T7] Kernel Offset: disabled [ 63.440557][ T7] Rebooting in 86400 seconds..