[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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 '10.128.0.194' (ECDSA) to the list of known hosts. 2020/06/18 06:39:28 fuzzer started 2020/06/18 06:39:28 connecting to host at 10.128.0.26:43423 2020/06/18 06:39:28 checking machine... 2020/06/18 06:39:28 checking revisions... 2020/06/18 06:39:28 testing simple program... syzkaller login: [ 60.652360][ T6841] IPVS: ftp: loaded support on port[0] = 21 2020/06/18 06:39:29 building call list... [ 61.002223][ T166] tipc: TX() has been purged, node left! [ 61.504578][ T166] ================================================================== [ 61.512824][ T166] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.520713][ T166] Write of size 1 at addr ffff8880a92981e4 by task kworker/u4:5/166 [ 61.528676][ T166] [ 61.531007][ T166] CPU: 1 PID: 166 Comm: kworker/u4:5 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.539493][ T166] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.549548][ T166] Workqueue: netns cleanup_net [ 61.554305][ T166] Call Trace: [ 61.557598][ T166] dump_stack+0x18f/0x20d [ 61.561926][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.567472][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.573008][ T166] ? afs_put_call+0xa40/0xa40 [ 61.577683][ T166] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.584711][ T166] ? vprintk_func+0x97/0x1a6 [ 61.589317][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.594876][ T166] kasan_report.cold+0x1f/0x37 [ 61.599643][ T166] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.605271][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.610818][ T166] afs_wake_up_async_call+0x6aa/0x770 [ 61.616183][ T166] ? afs_close_socket+0x320/0x320 [ 61.621228][ T166] ? afs_put_call+0xa40/0xa40 [ 61.625903][ T166] rxrpc_notify_socket+0x1db/0x5d0 [ 61.631015][ T166] ? afs_put_call+0xa40/0xa40 [ 61.635693][ T166] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.642120][ T166] rxrpc_call_completed+0xca/0xf0 [ 61.647148][ T166] rxrpc_discard_prealloc+0x781/0xab0 [ 61.652621][ T166] ? lock_sock_nested+0x94/0x110 [ 61.657565][ T166] rxrpc_listen+0x147/0x360 [ 61.662071][ T166] afs_close_socket+0x95/0x320 [ 61.666838][ T166] ? afs_purge_servers+0x16d/0x300 [ 61.671948][ T166] ? afs_rx_discard_new_call+0x50/0x50 [ 61.677416][ T166] ? init_wait_var_entry+0x200/0x200 [ 61.683065][ T166] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.688702][ T166] ? check_preemption_disabled+0x38/0x220 [ 61.694447][ T166] afs_net_exit+0x1bc/0x310 [ 61.698970][ T166] ? afs_net_init+0xe30/0xe30 [ 61.703676][ T166] ops_exit_list.isra.0+0xa8/0x150 [ 61.708806][ T166] cleanup_net+0x511/0xa50 [ 61.713431][ T166] ? unregister_pernet_device+0x70/0x70 [ 61.718986][ T166] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.724995][ T166] process_one_work+0x965/0x1690 [ 61.729946][ T166] ? lock_release+0x800/0x800 [ 61.734623][ T166] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.740006][ T166] ? rwlock_bug.part.0+0x90/0x90 [ 61.744956][ T166] worker_thread+0x96/0xe10 [ 61.749473][ T166] ? process_one_work+0x1690/0x1690 [ 61.754671][ T166] kthread+0x3b5/0x4a0 [ 61.758739][ T166] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.764455][ T166] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.770177][ T166] ret_from_fork+0x1f/0x30 [ 61.774605][ T166] [ 61.776930][ T166] Allocated by task 6841: [ 61.781256][ T166] save_stack+0x1b/0x40 [ 61.785434][ T166] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.791066][ T166] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.796433][ T166] afs_alloc_call+0x55/0x630 [ 61.801018][ T166] afs_charge_preallocation+0xe9/0x2d0 [ 61.806486][ T166] afs_open_socket+0x292/0x360 [ 61.811266][ T166] afs_net_init+0xa6c/0xe30 [ 61.815765][ T166] ops_init+0xaf/0x420 [ 61.819828][ T166] setup_net+0x2de/0x860 [ 61.824067][ T166] copy_net_ns+0x293/0x590 [ 61.828479][ T166] create_new_namespaces+0x3fb/0xb30 [ 61.833763][ T166] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.839414][ T166] ksys_unshare+0x43d/0x8e0 [ 61.843912][ T166] __x64_sys_unshare+0x2d/0x40 [ 61.848684][ T166] do_syscall_64+0x60/0xe0 [ 61.853102][ T166] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.859067][ T166] [ 61.861390][ T166] Freed by task 166: [ 61.865284][ T166] save_stack+0x1b/0x40 [ 61.869435][ T166] __kasan_slab_free+0xf7/0x140 [ 61.874413][ T166] kfree+0x109/0x2b0 [ 61.878321][ T166] afs_put_call+0x585/0xa40 [ 61.882828][ T166] rxrpc_discard_prealloc+0x764/0xab0 [ 61.888195][ T166] rxrpc_listen+0x147/0x360 [ 61.892693][ T166] afs_close_socket+0x95/0x320 [ 61.897456][ T166] afs_net_exit+0x1bc/0x310 [ 61.901956][ T166] ops_exit_list.isra.0+0xa8/0x150 [ 61.907059][ T166] cleanup_net+0x511/0xa50 [ 61.911480][ T166] process_one_work+0x965/0x1690 [ 61.916412][ T166] worker_thread+0x96/0xe10 [ 61.920910][ T166] kthread+0x3b5/0x4a0 [ 61.924984][ T166] ret_from_fork+0x1f/0x30 [ 61.929390][ T166] [ 61.931725][ T166] The buggy address belongs to the object at ffff8880a9298000 [ 61.931725][ T166] which belongs to the cache kmalloc-1k of size 1024 [ 61.945794][ T166] The buggy address is located 484 bytes inside of [ 61.945794][ T166] 1024-byte region [ffff8880a9298000, ffff8880a9298400) [ 61.959178][ T166] The buggy address belongs to the page: [ 61.964828][ T166] page:ffffea0002a4a600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8880a9298800 [ 61.975249][ T166] flags: 0xfffe0000000200(slab) [ 61.980107][ T166] raw: 00fffe0000000200 ffffea00026a26c8 ffffea0002a36988 ffff8880aa000c40 [ 61.988726][ T166] raw: ffff8880a9298800 ffff8880a9298000 0000000100000001 0000000000000000 [ 61.997304][ T166] page dumped because: kasan: bad access detected [ 62.003708][ T166] [ 62.006028][ T166] Memory state around the buggy address: [ 62.011688][ T166] ffff8880a9298080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.019749][ T166] ffff8880a9298100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.027813][ T166] >ffff8880a9298180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.035871][ T166] ^ [ 62.043065][ T166] ffff8880a9298200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.051305][ T166] ffff8880a9298280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.059363][ T166] ================================================================== [ 62.067506][ T166] Disabling lock debugging due to kernel taint [ 62.073703][ T166] Kernel panic - not syncing: panic_on_warn set ... [ 62.080289][ T166] CPU: 1 PID: 166 Comm: kworker/u4:5 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.089995][ T166] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.100052][ T166] Workqueue: netns cleanup_net [ 62.104809][ T166] Call Trace: [ 62.108098][ T166] dump_stack+0x18f/0x20d [ 62.112427][ T166] ? afs_wake_up_async_call+0x680/0x770 [ 62.117971][ T166] ? afs_put_call+0xa40/0xa40 [ 62.122642][ T166] panic+0x2e3/0x75c [ 62.126538][ T166] ? __warn_printk+0xf3/0xf3 [ 62.131125][ T166] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.137277][ T166] ? trace_hardirqs_on+0x55/0x220 [ 62.142298][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.147834][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.153372][ T166] ? afs_put_call+0xa40/0xa40 [ 62.158079][ T166] end_report+0x4d/0x53 [ 62.162229][ T166] kasan_report.cold+0xd/0x37 [ 62.167054][ T166] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.172687][ T166] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.178230][ T166] afs_wake_up_async_call+0x6aa/0x770 [ 62.183595][ T166] ? afs_close_socket+0x320/0x320 [ 62.188613][ T166] ? afs_put_call+0xa40/0xa40 [ 62.193299][ T166] rxrpc_notify_socket+0x1db/0x5d0 [ 62.198429][ T166] ? afs_put_call+0xa40/0xa40 [ 62.203108][ T166] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.209655][ T166] rxrpc_call_completed+0xca/0xf0 [ 62.214682][ T166] rxrpc_discard_prealloc+0x781/0xab0 [ 62.220053][ T166] ? lock_sock_nested+0x94/0x110 [ 62.224990][ T166] rxrpc_listen+0x147/0x360 [ 62.229487][ T166] afs_close_socket+0x95/0x320 [ 62.234242][ T166] ? afs_purge_servers+0x16d/0x300 [ 62.239348][ T166] ? afs_rx_discard_new_call+0x50/0x50 [ 62.244802][ T166] ? init_wait_var_entry+0x200/0x200 [ 62.250083][ T166] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.255737][ T166] ? check_preemption_disabled+0x38/0x220 [ 62.261470][ T166] afs_net_exit+0x1bc/0x310 [ 62.265989][ T166] ? afs_net_init+0xe30/0xe30 [ 62.270659][ T166] ops_exit_list.isra.0+0xa8/0x150 [ 62.275765][ T166] cleanup_net+0x511/0xa50 [ 62.280182][ T166] ? unregister_pernet_device+0x70/0x70 [ 62.285735][ T166] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.291713][ T166] process_one_work+0x965/0x1690 [ 62.296648][ T166] ? lock_release+0x800/0x800 [ 62.301318][ T166] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.306797][ T166] ? rwlock_bug.part.0+0x90/0x90 [ 62.311737][ T166] worker_thread+0x96/0xe10 [ 62.316244][ T166] ? process_one_work+0x1690/0x1690 [ 62.321436][ T166] kthread+0x3b5/0x4a0 [ 62.325498][ T166] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.331236][ T166] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.336952][ T166] ret_from_fork+0x1f/0x30 [ 62.342684][ T166] Kernel Offset: disabled [ 62.347043][ T166] Rebooting in 86400 seconds..