[ OK ] Started Getty on tty3. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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... Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.142' (ECDSA) to the list of known hosts. 2020/06/19 07:26:38 fuzzer started 2020/06/19 07:26:38 connecting to host at 10.128.0.26:34643 2020/06/19 07:26:38 checking machine... 2020/06/19 07:26:38 checking revisions... 2020/06/19 07:26:38 testing simple program... syzkaller login: [ 62.103352][ T6810] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 07:26:38 building call list... [ 62.446088][ T7] tipc: TX() has been purged, node left! [ 62.958189][ T7] ================================================================== [ 62.966861][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.977988][ T7] Write of size 1 at addr ffff8880a6f1e9e4 by task kworker/u4:0/7 [ 62.985778][ T7] [ 62.988112][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.996272][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.006333][ T7] Workqueue: netns cleanup_net [ 63.011695][ T7] Call Trace: [ 63.014991][ T7] dump_stack+0x18f/0x20d [ 63.019340][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.025055][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.030599][ T7] ? afs_put_call+0xa40/0xa40 [ 63.035362][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 63.042561][ T7] ? vprintk_func+0x97/0x1a6 [ 63.047156][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.052698][ T7] kasan_report.cold+0x1f/0x37 [ 63.057467][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.063113][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.068669][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 63.074043][ T7] ? afs_close_socket+0x320/0x320 [ 63.079077][ T7] ? afs_put_call+0xa40/0xa40 [ 63.084187][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 63.089321][ T7] ? afs_put_call+0xa40/0xa40 [ 63.093997][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.100586][ T7] rxrpc_call_completed+0xca/0xf0 [ 63.105878][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 63.111260][ T7] ? lock_sock_nested+0x94/0x110 [ 63.116227][ T7] rxrpc_listen+0x147/0x360 [ 63.120755][ T7] afs_close_socket+0x95/0x320 [ 63.125520][ T7] ? afs_purge_servers+0x16d/0x300 [ 63.130632][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 63.136099][ T7] ? init_wait_var_entry+0x200/0x200 [ 63.141917][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.147547][ T7] ? check_preemption_disabled+0x38/0x220 [ 63.153268][ T7] afs_net_exit+0x1bc/0x310 [ 63.157767][ T7] ? afs_net_init+0xe30/0xe30 [ 63.162442][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 63.167726][ T7] cleanup_net+0x511/0xa50 [ 63.172237][ T7] ? unregister_pernet_device+0x70/0x70 [ 63.177786][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.183774][ T7] process_one_work+0x965/0x1690 [ 63.188725][ T7] ? lock_release+0x800/0x800 [ 63.193403][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.199213][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 63.204164][ T7] worker_thread+0x96/0xe10 [ 63.208852][ T7] ? process_one_work+0x1690/0x1690 [ 63.214054][ T7] kthread+0x3b5/0x4a0 [ 63.218119][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.223849][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.229618][ T7] ret_from_fork+0x1f/0x30 [ 63.234042][ T7] [ 63.236623][ T7] Allocated by task 6810: [ 63.241034][ T7] save_stack+0x1b/0x40 [ 63.245271][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 63.251080][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 63.256461][ T7] afs_alloc_call+0x55/0x630 [ 63.261043][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 63.266495][ T7] afs_open_socket+0x292/0x360 [ 63.271262][ T7] afs_net_init+0xa6c/0xe30 [ 63.275757][ T7] ops_init+0xaf/0x420 [ 63.280782][ T7] setup_net+0x2de/0x860 [ 63.285016][ T7] copy_net_ns+0x293/0x590 [ 63.289428][ T7] create_new_namespaces+0x3fb/0xb30 [ 63.294716][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 63.300429][ T7] ksys_unshare+0x43d/0x8e0 [ 63.305015][ T7] __x64_sys_unshare+0x2d/0x40 [ 63.309792][ T7] do_syscall_64+0x60/0xe0 [ 63.314207][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 63.320106][ T7] [ 63.322435][ T7] Freed by task 7: [ 63.326152][ T7] save_stack+0x1b/0x40 [ 63.330330][ T7] __kasan_slab_free+0xf7/0x140 [ 63.335259][ T7] kfree+0x109/0x2b0 [ 63.339153][ T7] afs_put_call+0x585/0xa40 [ 63.343677][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 63.349052][ T7] rxrpc_listen+0x147/0x360 [ 63.353638][ T7] afs_close_socket+0x95/0x320 [ 63.358412][ T7] afs_net_exit+0x1bc/0x310 [ 63.362914][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 63.368135][ T7] cleanup_net+0x511/0xa50 [ 63.372568][ T7] process_one_work+0x965/0x1690 [ 63.377686][ T7] worker_thread+0x96/0xe10 [ 63.382197][ T7] kthread+0x3b5/0x4a0 [ 63.386280][ T7] ret_from_fork+0x1f/0x30 [ 63.390689][ T7] [ 63.393025][ T7] The buggy address belongs to the object at ffff8880a6f1e800 [ 63.393025][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 63.407596][ T7] The buggy address is located 484 bytes inside of [ 63.407596][ T7] 1024-byte region [ffff8880a6f1e800, ffff8880a6f1ec00) [ 63.422278][ T7] The buggy address belongs to the page: [ 63.429011][ T7] page:ffffea00029bc780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 63.438306][ T7] flags: 0xfffe0000000200(slab) [ 63.443193][ T7] raw: 00fffe0000000200 ffffea0002877408 ffffea0002a2c408 ffff8880aa000c40 [ 63.452054][ T7] raw: 0000000000000000 ffff8880a6f1e000 0000000100000002 0000000000000000 [ 63.460804][ T7] page dumped because: kasan: bad access detected [ 63.467205][ T7] [ 63.469524][ T7] Memory state around the buggy address: [ 63.475155][ T7] ffff8880a6f1e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.483221][ T7] ffff8880a6f1e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.491279][ T7] >ffff8880a6f1e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.499375][ T7] ^ [ 63.506563][ T7] ffff8880a6f1ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.514619][ T7] ffff8880a6f1ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.522691][ T7] ================================================================== [ 63.530777][ T7] Disabling lock debugging due to kernel taint [ 63.537011][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 63.543603][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.553665][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.563827][ T7] Workqueue: netns cleanup_net [ 63.568596][ T7] Call Trace: [ 63.571894][ T7] dump_stack+0x18f/0x20d [ 63.576237][ T7] ? afs_wake_up_async_call+0x680/0x770 [ 63.581818][ T7] ? afs_put_call+0xa40/0xa40 [ 63.586514][ T7] panic+0x2e3/0x75c [ 63.590851][ T7] ? __warn_printk+0xf3/0xf3 [ 63.595448][ T7] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.601700][ T7] ? trace_hardirqs_on+0x55/0x220 [ 63.606726][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.614213][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.619752][ T7] ? afs_put_call+0xa40/0xa40 [ 63.624427][ T7] end_report+0x4d/0x53 [ 63.628582][ T7] kasan_report.cold+0xd/0x37 [ 63.635861][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.641482][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.647031][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 63.652400][ T7] ? afs_close_socket+0x320/0x320 [ 63.657423][ T7] ? afs_put_call+0xa40/0xa40 [ 63.662104][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 63.667219][ T7] ? afs_put_call+0xa40/0xa40 [ 63.671892][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.678567][ T7] rxrpc_call_completed+0xca/0xf0 [ 63.683598][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 63.688967][ T7] ? lock_sock_nested+0x94/0x110 [ 63.693912][ T7] rxrpc_listen+0x147/0x360 [ 63.698434][ T7] afs_close_socket+0x95/0x320 [ 63.703201][ T7] ? afs_purge_servers+0x16d/0x300 [ 63.708400][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 63.713864][ T7] ? init_wait_var_entry+0x200/0x200 [ 63.719145][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.724776][ T7] ? check_preemption_disabled+0x38/0x220 [ 63.730575][ T7] afs_net_exit+0x1bc/0x310 [ 63.735073][ T7] ? afs_net_init+0xe30/0xe30 [ 63.739865][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 63.744981][ T7] cleanup_net+0x511/0xa50 [ 63.749484][ T7] ? unregister_pernet_device+0x70/0x70 [ 63.755085][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.761611][ T7] process_one_work+0x965/0x1690 [ 63.766550][ T7] ? lock_release+0x800/0x800 [ 63.771221][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.776612][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 63.781549][ T7] worker_thread+0x96/0xe10 [ 63.786576][ T7] ? process_one_work+0x1690/0x1690 [ 63.791792][ T7] kthread+0x3b5/0x4a0 [ 63.795880][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.801766][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.807505][ T7] ret_from_fork+0x1f/0x30 [ 63.813474][ T7] Kernel Offset: disabled [ 63.817914][ T7] Rebooting in 86400 seconds..