[ OK ] Started Getty on tty2. [ 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 '10.128.0.150' (ECDSA) to the list of known hosts. 2020/06/19 01:48:38 fuzzer started 2020/06/19 01:48:38 connecting to host at 10.128.0.26:39817 2020/06/19 01:48:38 checking machine... 2020/06/19 01:48:38 checking revisions... 2020/06/19 01:48:38 testing simple program... syzkaller login: [ 56.730476][ T6823] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 01:48:39 building call list... [ 57.073930][ T21] tipc: TX() has been purged, node left! [ 57.616256][ T21] ================================================================== [ 57.624502][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 57.634296][ T21] Write of size 1 at addr ffff88808e5bd9e4 by task kworker/u4:1/21 [ 57.643836][ T21] [ 57.646385][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-next-20200618-syzkaller #0 [ 57.656533][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.666995][ T21] Workqueue: netns cleanup_net [ 57.671765][ T21] Call Trace: [ 57.675330][ T21] dump_stack+0x18f/0x20d [ 57.679853][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.687819][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.693369][ T21] ? afs_put_call+0xa40/0xa40 [ 57.698155][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 57.705842][ T21] ? vprintk_func+0x97/0x1a6 [ 57.710701][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.716589][ T21] kasan_report.cold+0x1f/0x37 [ 57.721543][ T21] ? rcu_read_lock_held_common+0x71/0xa0 [ 57.727175][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.732812][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 57.738269][ T21] ? afs_close_socket+0x320/0x320 [ 57.743380][ T21] ? afs_put_call+0xa40/0xa40 [ 57.748074][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 57.754247][ T21] ? afs_put_call+0xa40/0xa40 [ 57.759284][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 57.765893][ T21] rxrpc_call_completed+0xca/0xf0 [ 57.770937][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 57.776399][ T21] ? lock_sock_nested+0x94/0x110 [ 57.781946][ T21] rxrpc_listen+0x147/0x360 [ 57.787861][ T21] afs_close_socket+0x95/0x320 [ 57.793058][ T21] ? afs_purge_servers+0x16d/0x300 [ 57.798567][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 57.814083][ T21] ? init_wait_var_entry+0x200/0x200 [ 57.819386][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 57.825292][ T21] ? check_preemption_disabled+0x38/0x220 [ 57.831018][ T21] afs_net_exit+0x1bc/0x310 [ 57.835884][ T21] ? afs_net_init+0xe30/0xe30 [ 57.840584][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 57.845703][ T21] cleanup_net+0x511/0xa50 [ 57.850141][ T21] ? unregister_pernet_device+0x70/0x70 [ 57.855718][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 57.862038][ T21] process_one_work+0x965/0x1690 [ 57.867031][ T21] ? lock_release+0x800/0x800 [ 57.871741][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 57.877144][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 57.882127][ T21] worker_thread+0x96/0xe10 [ 57.886675][ T21] ? process_one_work+0x1690/0x1690 [ 57.891915][ T21] kthread+0x3b5/0x4a0 [ 57.896019][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.901850][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.907584][ T21] ret_from_fork+0x1f/0x30 [ 57.912023][ T21] [ 57.914363][ T21] Allocated by task 6823: [ 57.918801][ T21] save_stack+0x1b/0x40 [ 57.922970][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 57.928610][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 57.933994][ T21] afs_alloc_call+0x55/0x630 [ 57.938594][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 57.944492][ T21] afs_open_socket+0x292/0x360 [ 57.949262][ T21] afs_net_init+0xa6c/0xe30 [ 57.955763][ T21] ops_init+0xaf/0x420 [ 57.959956][ T21] setup_net+0x2de/0x860 [ 57.964212][ T21] copy_net_ns+0x293/0x590 [ 57.968633][ T21] create_new_namespaces+0x3fb/0xb30 [ 57.973919][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 57.979549][ T21] ksys_unshare+0x445/0x8e0 [ 57.984056][ T21] __x64_sys_unshare+0x2d/0x40 [ 57.988828][ T21] do_syscall_64+0x60/0xe0 [ 57.993244][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 57.999142][ T21] [ 58.001474][ T21] Freed by task 21: [ 58.005305][ T21] save_stack+0x1b/0x40 [ 58.009476][ T21] __kasan_slab_free+0xf7/0x140 [ 58.014333][ T21] kfree+0x109/0x2b0 [ 58.018229][ T21] afs_put_call+0x585/0xa40 [ 58.022742][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 58.028145][ T21] rxrpc_listen+0x147/0x360 [ 58.032671][ T21] afs_close_socket+0x95/0x320 [ 58.037437][ T21] afs_net_exit+0x1bc/0x310 [ 58.041943][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 58.047065][ T21] cleanup_net+0x511/0xa50 [ 58.051519][ T21] process_one_work+0x965/0x1690 [ 58.056467][ T21] worker_thread+0x96/0xe10 [ 58.060990][ T21] kthread+0x3b5/0x4a0 [ 58.065081][ T21] ret_from_fork+0x1f/0x30 [ 58.069590][ T21] [ 58.071925][ T21] The buggy address belongs to the object at ffff88808e5bd800 [ 58.071925][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 58.086207][ T21] The buggy address is located 484 bytes inside of [ 58.086207][ T21] 1024-byte region [ffff88808e5bd800, ffff88808e5bdc00) [ 58.099657][ T21] The buggy address belongs to the page: [ 58.105386][ T21] page:ffffea0002396f40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 58.114493][ T21] flags: 0xfffe0000000200(slab) [ 58.119344][ T21] raw: 00fffe0000000200 ffffea00025bdb48 ffffea0002447c48 ffff8880aa000c40 [ 58.127952][ T21] raw: 0000000000000000 ffff88808e5bd000 0000000100000002 0000000000000000 [ 58.136529][ T21] page dumped because: kasan: bad access detected [ 58.142935][ T21] [ 58.145257][ T21] Memory state around the buggy address: [ 58.150890][ T21] ffff88808e5bd880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 58.158954][ T21] ffff88808e5bd900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 58.167047][ T21] >ffff88808e5bd980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 58.175102][ T21] ^ [ 58.182461][ T21] ffff88808e5bda00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 58.190972][ T21] ffff88808e5bda80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 58.199033][ T21] ================================================================== [ 58.207096][ T21] Disabling lock debugging due to kernel taint [ 58.213827][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 58.220414][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-next-20200618-syzkaller #0 [ 58.231243][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 58.241389][ T21] Workqueue: netns cleanup_net [ 58.246148][ T21] Call Trace: [ 58.249532][ T21] dump_stack+0x18f/0x20d [ 58.253862][ T21] ? afs_wake_up_async_call+0x660/0x770 [ 58.259493][ T21] ? afs_put_call+0xa40/0xa40 [ 58.264160][ T21] panic+0x2e3/0x75c [ 58.268049][ T21] ? __warn_printk+0xf3/0xf3 [ 58.272634][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 58.278783][ T21] ? trace_hardirqs_on+0x55/0x220 [ 58.283800][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 58.289520][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 58.295065][ T21] ? afs_put_call+0xa40/0xa40 [ 58.299750][ T21] end_report+0x4d/0x53 [ 58.304251][ T21] kasan_report.cold+0xd/0x37 [ 58.308920][ T21] ? rcu_read_lock_held_common+0x71/0xa0 [ 58.314542][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 58.320078][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 58.325447][ T21] ? afs_close_socket+0x320/0x320 [ 58.330471][ T21] ? afs_put_call+0xa40/0xa40 [ 58.335139][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 58.340242][ T21] ? afs_put_call+0xa40/0xa40 [ 58.344918][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 58.351333][ T21] rxrpc_call_completed+0xca/0xf0 [ 58.356352][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 58.361731][ T21] ? lock_sock_nested+0x94/0x110 [ 58.366659][ T21] rxrpc_listen+0x147/0x360 [ 58.371174][ T21] afs_close_socket+0x95/0x320 [ 58.375929][ T21] ? afs_purge_servers+0x16d/0x300 [ 58.381032][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 58.386483][ T21] ? init_wait_var_entry+0x200/0x200 [ 58.392299][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 58.397929][ T21] ? check_preemption_disabled+0x38/0x220 [ 58.403641][ T21] afs_net_exit+0x1bc/0x310 [ 58.408134][ T21] ? afs_net_init+0xe30/0xe30 [ 58.412811][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 58.417916][ T21] cleanup_net+0x511/0xa50 [ 58.422845][ T21] ? unregister_pernet_device+0x70/0x70 [ 58.428398][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 58.434391][ T21] process_one_work+0x965/0x1690 [ 58.439445][ T21] ? lock_release+0x800/0x800 [ 58.444141][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 58.449514][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 58.454461][ T21] worker_thread+0x96/0xe10 [ 58.458974][ T21] ? process_one_work+0x1690/0x1690 [ 58.464177][ T21] kthread+0x3b5/0x4a0 [ 58.468249][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 58.474065][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 58.479792][ T21] ret_from_fork+0x1f/0x30 [ 58.485528][ T21] Kernel Offset: disabled [ 58.489865][ T21] Rebooting in 86400 seconds..