[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ 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. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.17' (ECDSA) to the list of known hosts. 2020/06/17 05:28:12 fuzzer started 2020/06/17 05:28:13 connecting to host at 10.128.0.26:45365 2020/06/17 05:28:13 checking machine... 2020/06/17 05:28:13 checking revisions... 2020/06/17 05:28:13 testing simple program... syzkaller login: [ 60.944044][ T6842] IPVS: ftp: loaded support on port[0] = 21 2020/06/17 05:28:13 building call list... [ 61.282494][ T4386] tipc: TX() has been purged, node left! [ 61.784487][ T4386] ================================================================== [ 61.792729][ T4386] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.800620][ T4386] Write of size 1 at addr ffff8880a3b7c9e4 by task kworker/u4:5/4386 [ 61.808682][ T4386] [ 61.811012][ T4386] CPU: 1 PID: 4386 Comm: kworker/u4:5 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.819414][ T4386] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.829473][ T4386] Workqueue: netns cleanup_net [ 61.834231][ T4386] Call Trace: [ 61.837698][ T4386] dump_stack+0x18f/0x20d [ 61.842115][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.847658][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.853198][ T4386] ? afs_put_call+0xa40/0xa40 [ 61.858483][ T4386] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.865514][ T4386] ? vprintk_func+0x97/0x1a6 [ 61.870107][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.878272][ T4386] kasan_report.cold+0x1f/0x37 [ 61.883040][ T4386] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.888669][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.894216][ T4386] afs_wake_up_async_call+0x6aa/0x770 [ 61.899597][ T4386] ? afs_close_socket+0x320/0x320 [ 61.904631][ T4386] ? afs_put_call+0xa40/0xa40 [ 61.909306][ T4386] rxrpc_notify_socket+0x1db/0x5d0 [ 61.914422][ T4386] ? afs_put_call+0xa40/0xa40 [ 61.919138][ T4386] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.925555][ T4386] rxrpc_call_completed+0xca/0xf0 [ 61.930586][ T4386] rxrpc_discard_prealloc+0x781/0xab0 [ 61.935962][ T4386] ? lock_sock_nested+0x94/0x110 [ 61.940904][ T4386] rxrpc_listen+0x147/0x360 [ 61.945411][ T4386] afs_close_socket+0x95/0x320 [ 61.950176][ T4386] ? afs_purge_servers+0x16d/0x300 [ 61.955290][ T4386] ? afs_rx_discard_new_call+0x50/0x50 [ 61.960756][ T4386] ? init_wait_var_entry+0x200/0x200 [ 61.966056][ T4386] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.971689][ T4386] ? check_preemption_disabled+0x38/0x220 [ 61.977415][ T4386] afs_net_exit+0x1bc/0x310 [ 61.981917][ T4386] ? afs_net_init+0xe30/0xe30 [ 61.986679][ T4386] ops_exit_list.isra.0+0xa8/0x150 [ 61.991797][ T4386] cleanup_net+0x511/0xa50 [ 61.996302][ T4386] ? unregister_pernet_device+0x70/0x70 [ 62.001885][ T4386] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.007894][ T4386] process_one_work+0x965/0x1690 [ 62.012850][ T4386] ? lock_release+0x800/0x800 [ 62.017535][ T4386] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.022912][ T4386] ? rwlock_bug.part.0+0x90/0x90 [ 62.027861][ T4386] worker_thread+0x96/0xe10 [ 62.032818][ T4386] ? process_one_work+0x1690/0x1690 [ 62.038019][ T4386] kthread+0x3b5/0x4a0 [ 62.042086][ T4386] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.047976][ T4386] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.053802][ T4386] ret_from_fork+0x1f/0x30 [ 62.058231][ T4386] [ 62.060554][ T4386] Allocated by task 6842: [ 62.064883][ T4386] save_stack+0x1b/0x40 [ 62.069038][ T4386] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.074668][ T4386] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.080037][ T4386] afs_alloc_call+0x55/0x630 [ 62.084624][ T4386] afs_charge_preallocation+0xe9/0x2d0 [ 62.090186][ T4386] afs_open_socket+0x292/0x360 [ 62.094971][ T4386] afs_net_init+0xa6c/0xe30 [ 62.099467][ T4386] ops_init+0xaf/0x420 [ 62.103529][ T4386] setup_net+0x2de/0x860 [ 62.107777][ T4386] copy_net_ns+0x293/0x590 [ 62.112192][ T4386] create_new_namespaces+0x3fb/0xb30 [ 62.117474][ T4386] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.123104][ T4386] ksys_unshare+0x43d/0x8e0 [ 62.127605][ T4386] __x64_sys_unshare+0x2d/0x40 [ 62.132367][ T4386] do_syscall_64+0x60/0xe0 [ 62.136787][ T4386] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.142666][ T4386] [ 62.144989][ T4386] Freed by task 4386: [ 62.149062][ T4386] save_stack+0x1b/0x40 [ 62.153213][ T4386] __kasan_slab_free+0xf7/0x140 [ 62.158058][ T4386] kfree+0x109/0x2b0 [ 62.163686][ T4386] afs_put_call+0x585/0xa40 [ 62.168277][ T4386] rxrpc_discard_prealloc+0x764/0xab0 [ 62.173645][ T4386] rxrpc_listen+0x147/0x360 [ 62.178143][ T4386] afs_close_socket+0x95/0x320 [ 62.182900][ T4386] afs_net_exit+0x1bc/0x310 [ 62.187399][ T4386] ops_exit_list.isra.0+0xa8/0x150 [ 62.192513][ T4386] cleanup_net+0x511/0xa50 [ 62.196926][ T4386] process_one_work+0x965/0x1690 [ 62.202206][ T4386] worker_thread+0x96/0xe10 [ 62.206709][ T4386] kthread+0x3b5/0x4a0 [ 62.210782][ T4386] ret_from_fork+0x1f/0x30 [ 62.215187][ T4386] [ 62.217513][ T4386] The buggy address belongs to the object at ffff8880a3b7c800 [ 62.217513][ T4386] which belongs to the cache kmalloc-1k of size 1024 [ 62.231585][ T4386] The buggy address is located 484 bytes inside of [ 62.231585][ T4386] 1024-byte region [ffff8880a3b7c800, ffff8880a3b7cc00) [ 62.244946][ T4386] The buggy address belongs to the page: [ 62.250582][ T4386] page:ffffea00028edf00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.259681][ T4386] flags: 0xfffe0000000200(slab) [ 62.264535][ T4386] raw: 00fffe0000000200 ffffea000256ca08 ffffea000251aec8 ffff8880aa000c40 [ 62.273160][ T4386] raw: 0000000000000000 ffff8880a3b7c000 0000000100000002 0000000000000000 [ 62.281759][ T4386] page dumped because: kasan: bad access detected [ 62.288183][ T4386] [ 62.290524][ T4386] Memory state around the buggy address: [ 62.296174][ T4386] ffff8880a3b7c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.304259][ T4386] ffff8880a3b7c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.312321][ T4386] >ffff8880a3b7c980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.320390][ T4386] ^ [ 62.327583][ T4386] ffff8880a3b7ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.335641][ T4386] ffff8880a3b7ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.343721][ T4386] ================================================================== [ 62.351818][ T4386] Disabling lock debugging due to kernel taint [ 62.358013][ T4386] Kernel panic - not syncing: panic_on_warn set ... [ 62.364601][ T4386] CPU: 1 PID: 4386 Comm: kworker/u4:5 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.374392][ T4386] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.384447][ T4386] Workqueue: netns cleanup_net [ 62.389195][ T4386] Call Trace: [ 62.392481][ T4386] dump_stack+0x18f/0x20d [ 62.396814][ T4386] ? afs_wake_up_async_call+0x670/0x770 [ 62.402438][ T4386] ? afs_put_call+0xa40/0xa40 [ 62.407245][ T4386] panic+0x2e3/0x75c [ 62.411167][ T4386] ? __warn_printk+0xf3/0xf3 [ 62.415768][ T4386] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.421927][ T4386] ? trace_hardirqs_on+0x55/0x220 [ 62.426952][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.432494][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.438049][ T4386] ? afs_put_call+0xa40/0xa40 [ 62.442733][ T4386] end_report+0x4d/0x53 [ 62.446891][ T4386] kasan_report.cold+0xd/0x37 [ 62.451573][ T4386] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.457214][ T4386] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.462762][ T4386] afs_wake_up_async_call+0x6aa/0x770 [ 62.468132][ T4386] ? afs_close_socket+0x320/0x320 [ 62.473243][ T4386] ? afs_put_call+0xa40/0xa40 [ 62.477917][ T4386] rxrpc_notify_socket+0x1db/0x5d0 [ 62.483025][ T4386] ? afs_put_call+0xa40/0xa40 [ 62.487695][ T4386] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.494112][ T4386] rxrpc_call_completed+0xca/0xf0 [ 62.499134][ T4386] rxrpc_discard_prealloc+0x781/0xab0 [ 62.504786][ T4386] ? lock_sock_nested+0x94/0x110 [ 62.509738][ T4386] rxrpc_listen+0x147/0x360 [ 62.514247][ T4386] afs_close_socket+0x95/0x320 [ 62.519002][ T4386] ? afs_purge_servers+0x16d/0x300 [ 62.524109][ T4386] ? afs_rx_discard_new_call+0x50/0x50 [ 62.529654][ T4386] ? init_wait_var_entry+0x200/0x200 [ 62.534933][ T4386] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.540557][ T4386] ? check_preemption_disabled+0x38/0x220 [ 62.546273][ T4386] afs_net_exit+0x1bc/0x310 [ 62.550788][ T4386] ? afs_net_init+0xe30/0xe30 [ 62.555456][ T4386] ops_exit_list.isra.0+0xa8/0x150 [ 62.560562][ T4386] cleanup_net+0x511/0xa50 [ 62.564982][ T4386] ? unregister_pernet_device+0x70/0x70 [ 62.570524][ T4386] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.576500][ T4386] process_one_work+0x965/0x1690 [ 62.581433][ T4386] ? lock_release+0x800/0x800 [ 62.586115][ T4386] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.591505][ T4386] ? rwlock_bug.part.0+0x90/0x90 [ 62.596456][ T4386] worker_thread+0x96/0xe10 [ 62.600970][ T4386] ? process_one_work+0x1690/0x1690 [ 62.606163][ T4386] kthread+0x3b5/0x4a0 [ 62.610348][ T4386] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.616081][ T4386] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.621824][ T4386] ret_from_fork+0x1f/0x30 [ 62.627620][ T4386] Kernel Offset: disabled [ 62.631954][ T4386] Rebooting in 86400 seconds..