[ OK ] Started Getty on tty4. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ 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 '10.128.10.38' (ECDSA) to the list of known hosts. 2020/06/18 04:34:08 fuzzer started 2020/06/18 04:34:08 connecting to host at 10.128.0.26:35081 2020/06/18 04:34:08 checking machine... 2020/06/18 04:34:08 checking revisions... 2020/06/18 04:34:08 testing simple program... syzkaller login: [ 55.699817][ T6843] IPVS: ftp: loaded support on port[0] = 21 2020/06/18 04:34:08 building call list... [ 56.013234][ T79] tipc: TX() has been purged, node left! [ 56.515079][ T79] ================================================================== [ 56.523300][ T79] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 56.531187][ T79] Write of size 1 at addr ffff88809ee0c9e4 by task kworker/u4:3/79 [ 56.540277][ T79] [ 56.542608][ T79] CPU: 0 PID: 79 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-next-20200618-syzkaller #0 [ 56.552056][ T79] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.562162][ T79] Workqueue: netns cleanup_net [ 56.566950][ T79] Call Trace: [ 56.570246][ T79] dump_stack+0x18f/0x20d [ 56.574841][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 56.580381][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 56.585936][ T79] ? afs_put_call+0xa40/0xa40 [ 56.590624][ T79] print_address_description.constprop.0.cold+0xd3/0x413 [ 56.597661][ T79] ? vprintk_func+0x97/0x1a6 [ 56.603217][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 56.608757][ T79] kasan_report.cold+0x1f/0x37 [ 56.613525][ T79] ? rcu_read_lock_held_common+0x71/0xa0 [ 56.619155][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 56.624706][ T79] afs_wake_up_async_call+0x6aa/0x770 [ 56.630079][ T79] ? afs_close_socket+0x320/0x320 [ 56.635112][ T79] ? afs_put_call+0xa40/0xa40 [ 56.639784][ T79] rxrpc_notify_socket+0x1db/0x5d0 [ 56.644909][ T79] ? afs_put_call+0xa40/0xa40 [ 56.649579][ T79] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 56.655993][ T79] rxrpc_call_completed+0xca/0xf0 [ 56.661021][ T79] rxrpc_discard_prealloc+0x781/0xab0 [ 56.666398][ T79] ? lock_sock_nested+0x94/0x110 [ 56.671338][ T79] rxrpc_listen+0x147/0x360 [ 56.675878][ T79] afs_close_socket+0x95/0x320 [ 56.680728][ T79] ? afs_purge_servers+0x16d/0x300 [ 56.685847][ T79] ? afs_rx_discard_new_call+0x50/0x50 [ 56.691316][ T79] ? init_wait_var_entry+0x200/0x200 [ 56.696604][ T79] ? rcu_read_lock_held_common+0xa0/0xa0 [ 56.702230][ T79] ? check_preemption_disabled+0x38/0x220 [ 56.707953][ T79] afs_net_exit+0x1bc/0x310 [ 56.712455][ T79] ? afs_net_init+0xe30/0xe30 [ 56.717132][ T79] ops_exit_list.isra.0+0xa8/0x150 [ 56.722251][ T79] cleanup_net+0x511/0xa50 [ 56.726678][ T79] ? unregister_pernet_device+0x70/0x70 [ 56.732255][ T79] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 56.738513][ T79] process_one_work+0x965/0x1690 [ 56.743460][ T79] ? lock_release+0x800/0x800 [ 56.748134][ T79] ? pwq_dec_nr_in_flight+0x310/0x310 [ 56.753510][ T79] ? rwlock_bug.part.0+0x90/0x90 [ 56.758456][ T79] worker_thread+0x96/0xe10 [ 56.762978][ T79] ? process_one_work+0x1690/0x1690 [ 56.768459][ T79] kthread+0x3b5/0x4a0 [ 56.772554][ T79] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 56.778362][ T79] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 56.784106][ T79] ret_from_fork+0x1f/0x30 [ 56.788552][ T79] [ 56.790884][ T79] Allocated by task 6843: [ 56.795220][ T79] save_stack+0x1b/0x40 [ 56.799412][ T79] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 56.805063][ T79] kmem_cache_alloc_trace+0x153/0x7d0 [ 56.810472][ T79] afs_alloc_call+0x55/0x630 [ 56.815075][ T79] afs_charge_preallocation+0xe9/0x2d0 [ 56.820529][ T79] afs_open_socket+0x292/0x360 [ 56.825289][ T79] afs_net_init+0xa6c/0xe30 [ 56.829792][ T79] ops_init+0xaf/0x420 [ 56.833864][ T79] setup_net+0x2de/0x860 [ 56.838110][ T79] copy_net_ns+0x293/0x590 [ 56.842528][ T79] create_new_namespaces+0x3fb/0xb30 [ 56.847814][ T79] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 56.853445][ T79] ksys_unshare+0x445/0x8e0 [ 56.857951][ T79] __x64_sys_unshare+0x2d/0x40 [ 56.862742][ T79] do_syscall_64+0x60/0xe0 [ 56.867161][ T79] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 56.873048][ T79] [ 56.875369][ T79] Freed by task 79: [ 56.879177][ T79] save_stack+0x1b/0x40 [ 56.883331][ T79] __kasan_slab_free+0xf7/0x140 [ 56.888178][ T79] kfree+0x109/0x2b0 [ 56.892071][ T79] afs_put_call+0x585/0xa40 [ 56.896570][ T79] rxrpc_discard_prealloc+0x764/0xab0 [ 56.901940][ T79] rxrpc_listen+0x147/0x360 [ 56.906442][ T79] afs_close_socket+0x95/0x320 [ 56.911199][ T79] afs_net_exit+0x1bc/0x310 [ 56.915700][ T79] ops_exit_list.isra.0+0xa8/0x150 [ 56.920821][ T79] cleanup_net+0x511/0xa50 [ 56.925244][ T79] process_one_work+0x965/0x1690 [ 56.930188][ T79] worker_thread+0x96/0xe10 [ 56.934684][ T79] kthread+0x3b5/0x4a0 [ 56.938750][ T79] ret_from_fork+0x1f/0x30 [ 56.947277][ T79] [ 56.949614][ T79] The buggy address belongs to the object at ffff88809ee0c800 [ 56.949614][ T79] which belongs to the cache kmalloc-1k of size 1024 [ 56.963669][ T79] The buggy address is located 484 bytes inside of [ 56.963669][ T79] 1024-byte region [ffff88809ee0c800, ffff88809ee0cc00) [ 56.977030][ T79] The buggy address belongs to the page: [ 56.982692][ T79] page:ffffea00027b8300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 56.991807][ T79] flags: 0xfffe0000000200(slab) [ 56.996659][ T79] raw: 00fffe0000000200 ffffea00027a5848 ffffea0002676888 ffff8880aa000c40 [ 57.005345][ T79] raw: 0000000000000000 ffff88809ee0c000 0000000100000002 0000000000000000 [ 57.013919][ T79] page dumped because: kasan: bad access detected [ 57.020335][ T79] [ 57.022656][ T79] Memory state around the buggy address: [ 57.028289][ T79] ffff88809ee0c880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.036349][ T79] ffff88809ee0c900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.044499][ T79] >ffff88809ee0c980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.052550][ T79] ^ [ 57.059739][ T79] ffff88809ee0ca00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.067794][ T79] ffff88809ee0ca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.075846][ T79] ================================================================== [ 57.083899][ T79] Disabling lock debugging due to kernel taint [ 57.090095][ T79] Kernel panic - not syncing: panic_on_warn set ... [ 57.096765][ T79] CPU: 0 PID: 79 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-next-20200618-syzkaller #0 [ 57.107605][ T79] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.117664][ T79] Workqueue: netns cleanup_net [ 57.122416][ T79] Call Trace: [ 57.125703][ T79] dump_stack+0x18f/0x20d [ 57.130029][ T79] ? afs_wake_up_async_call+0x660/0x770 [ 57.135564][ T79] ? afs_put_call+0xa40/0xa40 [ 57.140319][ T79] panic+0x2e3/0x75c [ 57.144209][ T79] ? __warn_printk+0xf3/0xf3 [ 57.148825][ T79] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 57.154985][ T79] ? trace_hardirqs_on+0x55/0x220 [ 57.160016][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.165570][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.171108][ T79] ? afs_put_call+0xa40/0xa40 [ 57.176305][ T79] end_report+0x4d/0x53 [ 57.180456][ T79] kasan_report.cold+0xd/0x37 [ 57.185127][ T79] ? rcu_read_lock_held_common+0x71/0xa0 [ 57.190750][ T79] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.196387][ T79] afs_wake_up_async_call+0x6aa/0x770 [ 57.201747][ T79] ? afs_close_socket+0x320/0x320 [ 57.206762][ T79] ? afs_put_call+0xa40/0xa40 [ 57.211428][ T79] rxrpc_notify_socket+0x1db/0x5d0 [ 57.216531][ T79] ? afs_put_call+0xa40/0xa40 [ 57.221199][ T79] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 57.227610][ T79] rxrpc_call_completed+0xca/0xf0 [ 57.232627][ T79] rxrpc_discard_prealloc+0x781/0xab0 [ 57.237988][ T79] ? lock_sock_nested+0x94/0x110 [ 57.242918][ T79] rxrpc_listen+0x147/0x360 [ 57.247413][ T79] afs_close_socket+0x95/0x320 [ 57.252191][ T79] ? afs_purge_servers+0x16d/0x300 [ 57.257301][ T79] ? afs_rx_discard_new_call+0x50/0x50 [ 57.262753][ T79] ? init_wait_var_entry+0x200/0x200 [ 57.268030][ T79] ? rcu_read_lock_held_common+0xa0/0xa0 [ 57.273653][ T79] ? check_preemption_disabled+0x38/0x220 [ 57.279386][ T79] afs_net_exit+0x1bc/0x310 [ 57.283878][ T79] ? afs_net_init+0xe30/0xe30 [ 57.288580][ T79] ops_exit_list.isra.0+0xa8/0x150 [ 57.293684][ T79] cleanup_net+0x511/0xa50 [ 57.298104][ T79] ? unregister_pernet_device+0x70/0x70 [ 57.303641][ T79] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 57.309613][ T79] process_one_work+0x965/0x1690 [ 57.314548][ T79] ? lock_release+0x800/0x800 [ 57.319213][ T79] ? pwq_dec_nr_in_flight+0x310/0x310 [ 57.324582][ T79] ? rwlock_bug.part.0+0x90/0x90 [ 57.329523][ T79] worker_thread+0x96/0xe10 [ 57.334033][ T79] ? process_one_work+0x1690/0x1690 [ 57.339227][ T79] kthread+0x3b5/0x4a0 [ 57.343302][ T79] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.349113][ T79] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.354836][ T79] ret_from_fork+0x1f/0x30 [ 57.360575][ T79] Kernel Offset: disabled [ 57.364909][ T79] Rebooting in 86400 seconds..