[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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 '10.128.10.57' (ECDSA) to the list of known hosts. 2020/06/18 08:34:33 fuzzer started 2020/06/18 08:34:33 connecting to host at 10.128.0.26:43487 2020/06/18 08:34:33 checking machine... 2020/06/18 08:34:33 checking revisions... 2020/06/18 08:34:33 testing simple program... syzkaller login: [ 61.598392][ T6802] IPVS: ftp: loaded support on port[0] = 21 2020/06/18 08:34:33 building call list... [ 61.921761][ T244] tipc: TX() has been purged, node left! [ 62.433733][ T244] ================================================================== [ 62.442084][ T244] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.450112][ T244] Write of size 1 at addr ffff88809e29e9e4 by task kworker/u4:4/244 [ 62.458080][ T244] [ 62.460421][ T244] CPU: 1 PID: 244 Comm: kworker/u4:4 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.468739][ T244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.478827][ T244] Workqueue: netns cleanup_net [ 62.483604][ T244] Call Trace: [ 62.486898][ T244] dump_stack+0x18f/0x20d [ 62.491255][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.496972][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.502514][ T244] ? afs_put_call+0xa40/0xa40 [ 62.507191][ T244] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.514917][ T244] ? vprintk_func+0x97/0x1a6 [ 62.519509][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.525053][ T244] kasan_report.cold+0x1f/0x37 [ 62.529839][ T244] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.535489][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.541141][ T244] afs_wake_up_async_call+0x6aa/0x770 [ 62.546562][ T244] ? afs_close_socket+0x320/0x320 [ 62.551677][ T244] ? afs_put_call+0xa40/0xa40 [ 62.556448][ T244] rxrpc_notify_socket+0x1db/0x5d0 [ 62.561587][ T244] ? afs_put_call+0xa40/0xa40 [ 62.566267][ T244] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.572708][ T244] rxrpc_call_completed+0xca/0xf0 [ 62.577834][ T244] rxrpc_discard_prealloc+0x781/0xab0 [ 62.583473][ T244] ? lock_sock_nested+0x94/0x110 [ 62.588767][ T244] rxrpc_listen+0x147/0x360 [ 62.593383][ T244] afs_close_socket+0x95/0x320 [ 62.598145][ T244] ? afs_purge_servers+0x16d/0x300 [ 62.603518][ T244] ? afs_rx_discard_new_call+0x50/0x50 [ 62.608981][ T244] ? init_wait_var_entry+0x200/0x200 [ 62.614275][ T244] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.619909][ T244] ? check_preemption_disabled+0x38/0x220 [ 62.625636][ T244] afs_net_exit+0x1bc/0x310 [ 62.630136][ T244] ? afs_net_init+0xe30/0xe30 [ 62.634818][ T244] ops_exit_list.isra.0+0xa8/0x150 [ 62.639961][ T244] cleanup_net+0x511/0xa50 [ 62.644382][ T244] ? unregister_pernet_device+0x70/0x70 [ 62.650028][ T244] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.656019][ T244] process_one_work+0x965/0x1690 [ 62.660969][ T244] ? lock_release+0x800/0x800 [ 62.665680][ T244] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.671087][ T244] ? rwlock_bug.part.0+0x90/0x90 [ 62.676053][ T244] worker_thread+0x96/0xe10 [ 62.680577][ T244] ? process_one_work+0x1690/0x1690 [ 62.685865][ T244] kthread+0x3b5/0x4a0 [ 62.689942][ T244] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.695659][ T244] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.702255][ T244] ret_from_fork+0x1f/0x30 [ 62.706694][ T244] [ 62.709017][ T244] Allocated by task 6802: [ 62.713530][ T244] save_stack+0x1b/0x40 [ 62.717807][ T244] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.723445][ T244] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.728981][ T244] afs_alloc_call+0x55/0x630 [ 62.733827][ T244] afs_charge_preallocation+0xe9/0x2d0 [ 62.739390][ T244] afs_open_socket+0x292/0x360 [ 62.744853][ T244] afs_net_init+0xa6c/0xe30 [ 62.749837][ T244] ops_init+0xaf/0x420 [ 62.754083][ T244] setup_net+0x2de/0x860 [ 62.758323][ T244] copy_net_ns+0x293/0x590 [ 62.762955][ T244] create_new_namespaces+0x3fb/0xb30 [ 62.768427][ T244] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.774283][ T244] ksys_unshare+0x43d/0x8e0 [ 62.779335][ T244] __x64_sys_unshare+0x2d/0x40 [ 62.784394][ T244] do_syscall_64+0x60/0xe0 [ 62.789657][ T244] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.795539][ T244] [ 62.798035][ T244] Freed by task 244: [ 62.802219][ T244] save_stack+0x1b/0x40 [ 62.806400][ T244] __kasan_slab_free+0xf7/0x140 [ 62.812537][ T244] kfree+0x109/0x2b0 [ 62.817030][ T244] afs_put_call+0x585/0xa40 [ 62.821942][ T244] rxrpc_discard_prealloc+0x764/0xab0 [ 62.827678][ T244] rxrpc_listen+0x147/0x360 [ 62.832266][ T244] afs_close_socket+0x95/0x320 [ 62.837042][ T244] afs_net_exit+0x1bc/0x310 [ 62.841560][ T244] ops_exit_list.isra.0+0xa8/0x150 [ 62.847274][ T244] cleanup_net+0x511/0xa50 [ 62.851718][ T244] process_one_work+0x965/0x1690 [ 62.857966][ T244] worker_thread+0x96/0xe10 [ 62.862541][ T244] kthread+0x3b5/0x4a0 [ 62.866631][ T244] ret_from_fork+0x1f/0x30 [ 62.871052][ T244] [ 62.873516][ T244] The buggy address belongs to the object at ffff88809e29e800 [ 62.873516][ T244] which belongs to the cache kmalloc-1k of size 1024 [ 62.887999][ T244] The buggy address is located 484 bytes inside of [ 62.887999][ T244] 1024-byte region [ffff88809e29e800, ffff88809e29ec00) [ 62.902229][ T244] The buggy address belongs to the page: [ 62.908429][ T244] page:ffffea000278a780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.918228][ T244] flags: 0xfffe0000000200(slab) [ 62.923187][ T244] raw: 00fffe0000000200 ffffea00027e1208 ffffea00027c81c8 ffff8880aa000c40 [ 62.931794][ T244] raw: 0000000000000000 ffff88809e29e000 0000000100000002 0000000000000000 [ 62.941165][ T244] page dumped because: kasan: bad access detected [ 62.947569][ T244] [ 62.949888][ T244] Memory state around the buggy address: [ 62.955604][ T244] ffff88809e29e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.964187][ T244] ffff88809e29e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.972263][ T244] >ffff88809e29e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.980317][ T244] ^ [ 62.987512][ T244] ffff88809e29ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.995575][ T244] ffff88809e29ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.003632][ T244] ================================================================== [ 63.011788][ T244] Disabling lock debugging due to kernel taint [ 63.018016][ T244] Kernel panic - not syncing: panic_on_warn set ... [ 63.024612][ T244] CPU: 1 PID: 244 Comm: kworker/u4:4 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.034409][ T244] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.045174][ T244] Workqueue: netns cleanup_net [ 63.049958][ T244] Call Trace: [ 63.053256][ T244] dump_stack+0x18f/0x20d [ 63.057601][ T244] ? afs_wake_up_async_call+0x670/0x770 [ 63.063161][ T244] ? afs_put_call+0xa40/0xa40 [ 63.067846][ T244] panic+0x2e3/0x75c [ 63.071751][ T244] ? __warn_printk+0xf3/0xf3 [ 63.076348][ T244] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.083031][ T244] ? trace_hardirqs_on+0x55/0x220 [ 63.088059][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.093608][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.099161][ T244] ? afs_put_call+0xa40/0xa40 [ 63.103875][ T244] end_report+0x4d/0x53 [ 63.108032][ T244] kasan_report.cold+0xd/0x37 [ 63.112736][ T244] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.118386][ T244] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.124723][ T244] afs_wake_up_async_call+0x6aa/0x770 [ 63.130188][ T244] ? afs_close_socket+0x320/0x320 [ 63.135217][ T244] ? afs_put_call+0xa40/0xa40 [ 63.140327][ T244] rxrpc_notify_socket+0x1db/0x5d0 [ 63.146055][ T244] ? afs_put_call+0xa40/0xa40 [ 63.150735][ T244] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.157146][ T244] rxrpc_call_completed+0xca/0xf0 [ 63.162438][ T244] rxrpc_discard_prealloc+0x781/0xab0 [ 63.167809][ T244] ? lock_sock_nested+0x94/0x110 [ 63.172743][ T244] rxrpc_listen+0x147/0x360 [ 63.177329][ T244] afs_close_socket+0x95/0x320 [ 63.182201][ T244] ? afs_purge_servers+0x16d/0x300 [ 63.189501][ T244] ? afs_rx_discard_new_call+0x50/0x50 [ 63.195478][ T244] ? init_wait_var_entry+0x200/0x200 [ 63.200863][ T244] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.206493][ T244] ? check_preemption_disabled+0x38/0x220 [ 63.212301][ T244] afs_net_exit+0x1bc/0x310 [ 63.216806][ T244] ? afs_net_init+0xe30/0xe30 [ 63.221566][ T244] ops_exit_list.isra.0+0xa8/0x150 [ 63.226671][ T244] cleanup_net+0x511/0xa50 [ 63.231190][ T244] ? unregister_pernet_device+0x70/0x70 [ 63.236734][ T244] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.242710][ T244] process_one_work+0x965/0x1690 [ 63.247833][ T244] ? lock_release+0x800/0x800 [ 63.252592][ T244] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.257968][ T244] ? rwlock_bug.part.0+0x90/0x90 [ 63.262989][ T244] worker_thread+0x96/0xe10 [ 63.267501][ T244] ? process_one_work+0x1690/0x1690 [ 63.272698][ T244] kthread+0x3b5/0x4a0 [ 63.276759][ T244] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.282474][ T244] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.288197][ T244] ret_from_fork+0x1f/0x30 [ 63.294149][ T244] Kernel Offset: disabled [ 63.298562][ T244] Rebooting in 86400 seconds..