[ OK ] Listening on Load/Save RF Kill Switch Status /dev/rfkill Watch. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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 '10.128.0.134' (ECDSA) to the list of known hosts. 2020/06/19 05:16:57 fuzzer started 2020/06/19 05:16:57 connecting to host at 10.128.0.26:42625 2020/06/19 05:16:57 checking machine... 2020/06/19 05:16:57 checking revisions... 2020/06/19 05:16:57 testing simple program... syzkaller login: [ 60.567652][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 05:16:57 building call list... [ 60.954383][ T6760] tipc: TX() has been purged, node left! [ 61.506569][ T6760] ================================================================== [ 61.514812][ T6760] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.522728][ T6760] Write of size 1 at addr ffff8880822db1e4 by task kworker/u4:5/6760 [ 61.530873][ T6760] [ 61.533844][ T6760] CPU: 1 PID: 6760 Comm: kworker/u4:5 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.542255][ T6760] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.552339][ T6760] Workqueue: netns cleanup_net [ 61.557098][ T6760] Call Trace: [ 61.560393][ T6760] dump_stack+0x18f/0x20d [ 61.564729][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.570272][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.575814][ T6760] ? afs_put_call+0xa40/0xa40 [ 61.580515][ T6760] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.587547][ T6760] ? vprintk_func+0x97/0x1a6 [ 61.592168][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.597711][ T6760] kasan_report.cold+0x1f/0x37 [ 61.602485][ T6760] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.608114][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.613661][ T6760] afs_wake_up_async_call+0x6aa/0x770 [ 61.619196][ T6760] ? afs_close_socket+0x320/0x320 [ 61.624230][ T6760] ? afs_put_call+0xa40/0xa40 [ 61.629948][ T6760] rxrpc_notify_socket+0x1db/0x5d0 [ 61.635065][ T6760] ? afs_put_call+0xa40/0xa40 [ 61.639744][ T6760] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.646164][ T6760] rxrpc_call_completed+0xca/0xf0 [ 61.651310][ T6760] rxrpc_discard_prealloc+0x781/0xab0 [ 61.656691][ T6760] ? lock_sock_nested+0x94/0x110 [ 61.661635][ T6760] rxrpc_listen+0x147/0x360 [ 61.666164][ T6760] afs_close_socket+0x95/0x320 [ 61.670958][ T6760] ? afs_purge_servers+0x16d/0x300 [ 61.676073][ T6760] ? afs_rx_discard_new_call+0x50/0x50 [ 61.681537][ T6760] ? init_wait_var_entry+0x200/0x200 [ 61.686827][ T6760] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.692458][ T6760] ? check_preemption_disabled+0x38/0x220 [ 61.698187][ T6760] afs_net_exit+0x1bc/0x310 [ 61.702777][ T6760] ? afs_net_init+0xe30/0xe30 [ 61.707454][ T6760] ops_exit_list.isra.0+0xa8/0x150 [ 61.712575][ T6760] cleanup_net+0x511/0xa50 [ 61.717170][ T6760] ? unregister_pernet_device+0x70/0x70 [ 61.723414][ T6760] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.729838][ T6760] process_one_work+0x965/0x1690 [ 61.734788][ T6760] ? lock_release+0x800/0x800 [ 61.739552][ T6760] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.744928][ T6760] ? rwlock_bug.part.0+0x90/0x90 [ 61.749878][ T6760] worker_thread+0x96/0xe10 [ 61.754414][ T6760] ? process_one_work+0x1690/0x1690 [ 61.759631][ T6760] kthread+0x3b5/0x4a0 [ 61.763698][ T6760] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.769416][ T6760] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.775153][ T6760] ret_from_fork+0x1f/0x30 [ 61.779581][ T6760] [ 61.781904][ T6760] Allocated by task 6820: [ 61.786236][ T6760] save_stack+0x1b/0x40 [ 61.790391][ T6760] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.796021][ T6760] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.801424][ T6760] afs_alloc_call+0x55/0x630 [ 61.806022][ T6760] afs_charge_preallocation+0xe9/0x2d0 [ 61.811579][ T6760] afs_open_socket+0x292/0x360 [ 61.816336][ T6760] afs_net_init+0xa6c/0xe30 [ 61.821009][ T6760] ops_init+0xaf/0x420 [ 61.825076][ T6760] setup_net+0x2de/0x860 [ 61.829311][ T6760] copy_net_ns+0x293/0x590 [ 61.833724][ T6760] create_new_namespaces+0x3fb/0xb30 [ 61.839008][ T6760] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.844636][ T6760] ksys_unshare+0x43d/0x8e0 [ 61.849137][ T6760] __x64_sys_unshare+0x2d/0x40 [ 61.853893][ T6760] do_syscall_64+0x60/0xe0 [ 61.858305][ T6760] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.864180][ T6760] [ 61.866499][ T6760] Freed by task 6760: [ 61.870739][ T6760] save_stack+0x1b/0x40 [ 61.874888][ T6760] __kasan_slab_free+0xf7/0x140 [ 61.879732][ T6760] kfree+0x109/0x2b0 [ 61.883635][ T6760] afs_put_call+0x585/0xa40 [ 61.888138][ T6760] rxrpc_discard_prealloc+0x764/0xab0 [ 61.893505][ T6760] rxrpc_listen+0x147/0x360 [ 61.898010][ T6760] afs_close_socket+0x95/0x320 [ 61.902774][ T6760] afs_net_exit+0x1bc/0x310 [ 61.907293][ T6760] ops_exit_list.isra.0+0xa8/0x150 [ 61.912412][ T6760] cleanup_net+0x511/0xa50 [ 61.916868][ T6760] process_one_work+0x965/0x1690 [ 61.921815][ T6760] worker_thread+0x96/0xe10 [ 61.926331][ T6760] kthread+0x3b5/0x4a0 [ 61.930398][ T6760] ret_from_fork+0x1f/0x30 [ 61.936024][ T6760] [ 61.938367][ T6760] The buggy address belongs to the object at ffff8880822db000 [ 61.938367][ T6760] which belongs to the cache kmalloc-1k of size 1024 [ 61.952419][ T6760] The buggy address is located 484 bytes inside of [ 61.952419][ T6760] 1024-byte region [ffff8880822db000, ffff8880822db400) [ 61.966311][ T6760] The buggy address belongs to the page: [ 61.971944][ T6760] page:ffffea000208b6c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.981052][ T6760] flags: 0xfffe0000000200(slab) [ 61.985956][ T6760] raw: 00fffe0000000200 ffffea000208b608 ffffea000208b708 ffff8880aa000c40 [ 61.994550][ T6760] raw: 0000000000000000 ffff8880822db000 0000000100000002 0000000000000000 [ 62.003180][ T6760] page dumped because: kasan: bad access detected [ 62.009588][ T6760] [ 62.011912][ T6760] Memory state around the buggy address: [ 62.017540][ T6760] ffff8880822db080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.025607][ T6760] ffff8880822db100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.033750][ T6760] >ffff8880822db180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.041797][ T6760] ^ [ 62.048991][ T6760] ffff8880822db200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.057047][ T6760] ffff8880822db280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.065189][ T6760] ================================================================== [ 62.073239][ T6760] Disabling lock debugging due to kernel taint [ 62.079431][ T6760] Kernel panic - not syncing: panic_on_warn set ... [ 62.086014][ T6760] CPU: 1 PID: 6760 Comm: kworker/u4:5 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.095795][ T6760] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.105841][ T6760] Workqueue: netns cleanup_net [ 62.110671][ T6760] Call Trace: [ 62.113954][ T6760] dump_stack+0x18f/0x20d [ 62.118277][ T6760] ? afs_wake_up_async_call+0x680/0x770 [ 62.123807][ T6760] ? afs_put_call+0xa40/0xa40 [ 62.128472][ T6760] panic+0x2e3/0x75c [ 62.132533][ T6760] ? __warn_printk+0xf3/0xf3 [ 62.137121][ T6760] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.143269][ T6760] ? trace_hardirqs_on+0x55/0x220 [ 62.148284][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.153902][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.159448][ T6760] ? afs_put_call+0xa40/0xa40 [ 62.164289][ T6760] end_report+0x4d/0x53 [ 62.168448][ T6760] kasan_report.cold+0xd/0x37 [ 62.173128][ T6760] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.178757][ T6760] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.184298][ T6760] afs_wake_up_async_call+0x6aa/0x770 [ 62.189756][ T6760] ? afs_close_socket+0x320/0x320 [ 62.194784][ T6760] ? afs_put_call+0xa40/0xa40 [ 62.199500][ T6760] rxrpc_notify_socket+0x1db/0x5d0 [ 62.204612][ T6760] ? afs_put_call+0xa40/0xa40 [ 62.209285][ T6760] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.215705][ T6760] rxrpc_call_completed+0xca/0xf0 [ 62.220775][ T6760] rxrpc_discard_prealloc+0x781/0xab0 [ 62.226239][ T6760] ? lock_sock_nested+0x94/0x110 [ 62.231174][ T6760] rxrpc_listen+0x147/0x360 [ 62.235673][ T6760] afs_close_socket+0x95/0x320 [ 62.240440][ T6760] ? afs_purge_servers+0x16d/0x300 [ 62.245545][ T6760] ? afs_rx_discard_new_call+0x50/0x50 [ 62.250997][ T6760] ? init_wait_var_entry+0x200/0x200 [ 62.256278][ T6760] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.261906][ T6760] ? check_preemption_disabled+0x38/0x220 [ 62.267624][ T6760] afs_net_exit+0x1bc/0x310 [ 62.272155][ T6760] ? afs_net_init+0xe30/0xe30 [ 62.276825][ T6760] ops_exit_list.isra.0+0xa8/0x150 [ 62.281953][ T6760] cleanup_net+0x511/0xa50 [ 62.286978][ T6760] ? unregister_pernet_device+0x70/0x70 [ 62.292522][ T6760] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.298520][ T6760] process_one_work+0x965/0x1690 [ 62.303463][ T6760] ? lock_release+0x800/0x800 [ 62.308134][ T6760] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.313502][ T6760] ? rwlock_bug.part.0+0x90/0x90 [ 62.318523][ T6760] worker_thread+0x96/0xe10 [ 62.323025][ T6760] ? process_one_work+0x1690/0x1690 [ 62.328215][ T6760] kthread+0x3b5/0x4a0 [ 62.332277][ T6760] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.338090][ T6760] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.343805][ T6760] ret_from_fork+0x1f/0x30 [ 62.349575][ T6760] Kernel Offset: disabled [ 62.353952][ T6760] Rebooting in 86400 seconds..