[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.200' (ECDSA) to the list of known hosts. 2020/06/19 04:01:31 fuzzer started 2020/06/19 04:01:31 connecting to host at 10.128.0.26:45011 2020/06/19 04:01:31 checking machine... 2020/06/19 04:01:31 checking revisions... 2020/06/19 04:01:31 testing simple program... syzkaller login: [ 71.485357][ T6810] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 04:01:31 building call list... [ 71.816899][ T7] tipc: TX() has been purged, node left! [ 72.379014][ T7] ================================================================== [ 72.387492][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 72.395847][ T7] Write of size 1 at addr ffff888081b2a1e4 by task kworker/u4:0/7 [ 72.404520][ T7] [ 72.406858][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 72.415011][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 72.425083][ T7] Workqueue: netns cleanup_net [ 72.429863][ T7] Call Trace: [ 72.433231][ T7] dump_stack+0x18f/0x20d [ 72.437812][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 72.443846][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 72.449422][ T7] ? afs_put_call+0xa40/0xa40 [ 72.454107][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 72.461145][ T7] ? vprintk_func+0x97/0x1a6 [ 72.465872][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 72.471568][ T7] kasan_report.cold+0x1f/0x37 [ 72.476488][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 72.482129][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 72.487696][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 72.493199][ T7] ? afs_close_socket+0x320/0x320 [ 72.498371][ T7] ? afs_put_call+0xa40/0xa40 [ 72.503052][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 72.508198][ T7] ? afs_put_call+0xa40/0xa40 [ 72.512884][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 72.519306][ T7] rxrpc_call_completed+0xca/0xf0 [ 72.524373][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 72.529759][ T7] ? lock_sock_nested+0x94/0x110 [ 72.534718][ T7] rxrpc_listen+0x147/0x360 [ 72.539251][ T7] afs_close_socket+0x95/0x320 [ 72.544032][ T7] ? afs_purge_servers+0x16d/0x300 [ 72.549209][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 72.554719][ T7] ? init_wait_var_entry+0x200/0x200 [ 72.560027][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 72.565675][ T7] ? check_preemption_disabled+0x38/0x220 [ 72.571652][ T7] afs_net_exit+0x1bc/0x310 [ 72.576158][ T7] ? afs_net_init+0xe30/0xe30 [ 72.580852][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 72.585974][ T7] cleanup_net+0x511/0xa50 [ 72.590412][ T7] ? unregister_pernet_device+0x70/0x70 [ 72.596279][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 72.602457][ T7] process_one_work+0x965/0x1690 [ 72.607434][ T7] ? lock_release+0x800/0x800 [ 72.612139][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 72.617537][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 72.622700][ T7] worker_thread+0x96/0xe10 [ 72.627250][ T7] ? process_one_work+0x1690/0x1690 [ 72.632461][ T7] kthread+0x3b5/0x4a0 [ 72.636546][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 72.642375][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 72.648496][ T7] ret_from_fork+0x1f/0x30 [ 72.652943][ T7] [ 72.655367][ T7] Allocated by task 6810: [ 72.659895][ T7] save_stack+0x1b/0x40 [ 72.664081][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 72.669739][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 72.675126][ T7] afs_alloc_call+0x55/0x630 [ 72.679824][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 72.687262][ T7] afs_open_socket+0x292/0x360 [ 72.692637][ T7] afs_net_init+0xa6c/0xe30 [ 72.697604][ T7] ops_init+0xaf/0x420 [ 72.702387][ T7] setup_net+0x2de/0x860 [ 72.707388][ T7] copy_net_ns+0x293/0x590 [ 72.712982][ T7] create_new_namespaces+0x3fb/0xb30 [ 72.718896][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 72.726572][ T7] ksys_unshare+0x43d/0x8e0 [ 72.731375][ T7] __x64_sys_unshare+0x2d/0x40 [ 72.736238][ T7] do_syscall_64+0x60/0xe0 [ 72.741228][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 72.748141][ T7] [ 72.750729][ T7] Freed by task 7: [ 72.755357][ T7] save_stack+0x1b/0x40 [ 72.759516][ T7] __kasan_slab_free+0xf7/0x140 [ 72.764835][ T7] kfree+0x109/0x2b0 [ 72.769256][ T7] afs_put_call+0x585/0xa40 [ 72.774027][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 72.780867][ T7] rxrpc_listen+0x147/0x360 [ 72.785647][ T7] afs_close_socket+0x95/0x320 [ 72.790965][ T7] afs_net_exit+0x1bc/0x310 [ 72.795678][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 72.801329][ T7] cleanup_net+0x511/0xa50 [ 72.805933][ T7] process_one_work+0x965/0x1690 [ 72.811228][ T7] worker_thread+0x96/0xe10 [ 72.816670][ T7] kthread+0x3b5/0x4a0 [ 72.821193][ T7] ret_from_fork+0x1f/0x30 [ 72.826163][ T7] [ 72.829799][ T7] The buggy address belongs to the object at ffff888081b2a000 [ 72.829799][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 72.844427][ T7] The buggy address is located 484 bytes inside of [ 72.844427][ T7] 1024-byte region [ffff888081b2a000, ffff888081b2a400) [ 72.858634][ T7] The buggy address belongs to the page: [ 72.864379][ T7] page:ffffea000206ca80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 72.873810][ T7] flags: 0xfffe0000000200(slab) [ 72.879378][ T7] raw: 00fffe0000000200 ffffea000206ca08 ffffea000206cac8 ffff8880aa000c40 [ 72.890127][ T7] raw: 0000000000000000 ffff888081b2a000 0000000100000002 0000000000000000 [ 72.899972][ T7] page dumped because: kasan: bad access detected [ 72.908121][ T7] [ 72.910922][ T7] Memory state around the buggy address: [ 72.918351][ T7] ffff888081b2a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 72.928551][ T7] ffff888081b2a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 72.938995][ T7] >ffff888081b2a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 72.949724][ T7] ^ [ 72.958013][ T7] ffff888081b2a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 72.967068][ T7] ffff888081b2a280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 72.975520][ T7] ================================================================== [ 72.984769][ T7] Disabling lock debugging due to kernel taint [ 72.991544][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 72.998759][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 73.008567][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 73.020257][ T7] Workqueue: netns cleanup_net [ 73.025849][ T7] Call Trace: [ 73.029640][ T7] dump_stack+0x18f/0x20d [ 73.034881][ T7] ? afs_wake_up_async_call+0x670/0x770 [ 73.040719][ T7] ? afs_put_call+0xa40/0xa40 [ 73.045948][ T7] panic+0x2e3/0x75c [ 73.050102][ T7] ? __warn_printk+0xf3/0xf3 [ 73.055785][ T7] ? asm_common_interrupt+0x1e/0x40 [ 73.061358][ T7] ? trace_hardirqs_on+0x55/0x220 [ 73.066651][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 73.072331][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 73.077956][ T7] ? afs_put_call+0xa40/0xa40 [ 73.082986][ T7] end_report+0x4d/0x53 [ 73.087591][ T7] kasan_report.cold+0xd/0x37 [ 73.092559][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 73.098849][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 73.104397][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 73.109784][ T7] ? afs_close_socket+0x320/0x320 [ 73.115052][ T7] ? afs_put_call+0xa40/0xa40 [ 73.119736][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 73.124965][ T7] ? afs_put_call+0xa40/0xa40 [ 73.129645][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 73.136180][ T7] rxrpc_call_completed+0xca/0xf0 [ 73.141212][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 73.146601][ T7] ? lock_sock_nested+0x94/0x110 [ 73.151903][ T7] rxrpc_listen+0x147/0x360 [ 73.156419][ T7] afs_close_socket+0x95/0x320 [ 73.161186][ T7] ? afs_purge_servers+0x16d/0x300 [ 73.166345][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 73.171816][ T7] ? init_wait_var_entry+0x200/0x200 [ 73.177256][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 73.183039][ T7] ? check_preemption_disabled+0x38/0x220 [ 73.188939][ T7] afs_net_exit+0x1bc/0x310 [ 73.193439][ T7] ? afs_net_init+0xe30/0xe30 [ 73.198121][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 73.203243][ T7] cleanup_net+0x511/0xa50 [ 73.207810][ T7] ? unregister_pernet_device+0x70/0x70 [ 73.213391][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 73.219683][ T7] process_one_work+0x965/0x1690 [ 73.224657][ T7] ? lock_release+0x800/0x800 [ 73.229338][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 73.234745][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 73.239860][ T7] worker_thread+0x96/0xe10 [ 73.244373][ T7] ? process_one_work+0x1690/0x1690 [ 73.249574][ T7] kthread+0x3b5/0x4a0 [ 73.253641][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 73.259573][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 73.265400][ T7] ret_from_fork+0x1f/0x30 [ 73.271520][ T7] Kernel Offset: disabled [ 73.276000][ T7] Rebooting in 86400 seconds..