[ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.60' (ECDSA) to the list of known hosts. 2020/06/19 01:13:12 fuzzer started 2020/06/19 01:13:13 connecting to host at 10.128.0.26:40137 2020/06/19 01:13:13 checking machine... 2020/06/19 01:13:13 checking revisions... 2020/06/19 01:13:13 testing simple program... syzkaller login: [ 60.715341][ T6821] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 01:13:13 building call list... [ 61.068784][ T26] tipc: TX() has been purged, node left! [ 61.581083][ T26] ================================================================== [ 61.589478][ T26] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.597390][ T26] Write of size 1 at addr ffff88808e7849e4 by task kworker/u4:2/26 [ 61.605295][ T26] [ 61.607650][ T26] CPU: 0 PID: 26 Comm: kworker/u4:2 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.616136][ T26] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.626549][ T26] Workqueue: netns cleanup_net [ 61.631315][ T26] Call Trace: [ 61.634608][ T26] dump_stack+0x18f/0x20d [ 61.639470][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.645366][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.650927][ T26] ? afs_put_call+0xa40/0xa40 [ 61.655606][ T26] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.663273][ T26] ? vprintk_func+0x97/0x1a6 [ 61.667875][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.673424][ T26] kasan_report.cold+0x1f/0x37 [ 61.678199][ T26] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.684441][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.690036][ T26] afs_wake_up_async_call+0x6aa/0x770 [ 61.695406][ T26] ? afs_close_socket+0x320/0x320 [ 61.700436][ T26] ? afs_put_call+0xa40/0xa40 [ 61.705120][ T26] rxrpc_notify_socket+0x1db/0x5d0 [ 61.710361][ T26] ? afs_put_call+0xa40/0xa40 [ 61.715037][ T26] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.721452][ T26] rxrpc_call_completed+0xca/0xf0 [ 61.726491][ T26] rxrpc_discard_prealloc+0x781/0xab0 [ 61.731943][ T26] ? lock_sock_nested+0x94/0x110 [ 61.736891][ T26] rxrpc_listen+0x147/0x360 [ 61.741408][ T26] afs_close_socket+0x95/0x320 [ 61.746462][ T26] ? afs_purge_servers+0x16d/0x300 [ 61.751576][ T26] ? afs_rx_discard_new_call+0x50/0x50 [ 61.757037][ T26] ? init_wait_var_entry+0x200/0x200 [ 61.762329][ T26] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.767962][ T26] ? check_preemption_disabled+0x38/0x220 [ 61.773874][ T26] afs_net_exit+0x1bc/0x310 [ 61.778749][ T26] ? afs_net_init+0xe30/0xe30 [ 61.783706][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 61.789538][ T26] cleanup_net+0x511/0xa50 [ 61.794055][ T26] ? unregister_pernet_device+0x70/0x70 [ 61.799617][ T26] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.806042][ T26] process_one_work+0x965/0x1690 [ 61.810994][ T26] ? lock_release+0x800/0x800 [ 61.815762][ T26] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.821146][ T26] ? rwlock_bug.part.0+0x90/0x90 [ 61.826096][ T26] worker_thread+0x96/0xe10 [ 61.830624][ T26] ? process_one_work+0x1690/0x1690 [ 61.835825][ T26] kthread+0x3b5/0x4a0 [ 61.839895][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.845970][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.851725][ T26] ret_from_fork+0x1f/0x30 [ 61.856243][ T26] [ 61.858570][ T26] Allocated by task 6821: [ 61.862899][ T26] save_stack+0x1b/0x40 [ 61.867151][ T26] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.873150][ T26] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.878982][ T26] afs_alloc_call+0x55/0x630 [ 61.883571][ T26] afs_charge_preallocation+0xe9/0x2d0 [ 61.889422][ T26] afs_open_socket+0x292/0x360 [ 61.895485][ T26] afs_net_init+0xa6c/0xe30 [ 61.899987][ T26] ops_init+0xaf/0x420 [ 61.904052][ T26] setup_net+0x2de/0x860 [ 61.908294][ T26] copy_net_ns+0x293/0x590 [ 61.912894][ T26] create_new_namespaces+0x3fb/0xb30 [ 61.918277][ T26] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.923908][ T26] ksys_unshare+0x43d/0x8e0 [ 61.928513][ T26] __x64_sys_unshare+0x2d/0x40 [ 61.934575][ T26] do_syscall_64+0x60/0xe0 [ 61.939077][ T26] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.944975][ T26] [ 61.947315][ T26] Freed by task 26: [ 61.951118][ T26] save_stack+0x1b/0x40 [ 61.955285][ T26] __kasan_slab_free+0xf7/0x140 [ 61.960139][ T26] kfree+0x109/0x2b0 [ 61.964039][ T26] afs_put_call+0x585/0xa40 [ 61.968570][ T26] rxrpc_discard_prealloc+0x764/0xab0 [ 61.973950][ T26] rxrpc_listen+0x147/0x360 [ 61.978449][ T26] afs_close_socket+0x95/0x320 [ 61.983206][ T26] afs_net_exit+0x1bc/0x310 [ 61.987717][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 61.992819][ T26] cleanup_net+0x511/0xa50 [ 61.997241][ T26] process_one_work+0x965/0x1690 [ 62.002183][ T26] worker_thread+0x96/0xe10 [ 62.006682][ T26] kthread+0x3b5/0x4a0 [ 62.010747][ T26] ret_from_fork+0x1f/0x30 [ 62.016888][ T26] [ 62.019219][ T26] The buggy address belongs to the object at ffff88808e784800 [ 62.019219][ T26] which belongs to the cache kmalloc-1k of size 1024 [ 62.033286][ T26] The buggy address is located 484 bytes inside of [ 62.033286][ T26] 1024-byte region [ffff88808e784800, ffff88808e784c00) [ 62.046672][ T26] The buggy address belongs to the page: [ 62.052303][ T26] page:ffffea000239e100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.061404][ T26] flags: 0xfffe0000000200(slab) [ 62.066259][ T26] raw: 00fffe0000000200 ffffea0002521b88 ffffea00027a18c8 ffff8880aa000c40 [ 62.074925][ T26] raw: 0000000000000000 ffff88808e784000 0000000100000002 0000000000000000 [ 62.083504][ T26] page dumped because: kasan: bad access detected [ 62.089907][ T26] [ 62.092228][ T26] Memory state around the buggy address: [ 62.097854][ T26] ffff88808e784880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.105935][ T26] ffff88808e784900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.114089][ T26] >ffff88808e784980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.122158][ T26] ^ [ 62.129352][ T26] ffff88808e784a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.137453][ T26] ffff88808e784a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.145522][ T26] ================================================================== [ 62.153933][ T26] Disabling lock debugging due to kernel taint [ 62.160148][ T26] Kernel panic - not syncing: panic_on_warn set ... [ 62.166744][ T26] CPU: 0 PID: 26 Comm: kworker/u4:2 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.176357][ T26] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.186410][ T26] Workqueue: netns cleanup_net [ 62.191161][ T26] Call Trace: [ 62.196637][ T26] dump_stack+0x18f/0x20d [ 62.200972][ T26] ? afs_wake_up_async_call+0x670/0x770 [ 62.206516][ T26] ? afs_put_call+0xa40/0xa40 [ 62.211189][ T26] panic+0x2e3/0x75c [ 62.215370][ T26] ? __warn_printk+0xf3/0xf3 [ 62.219954][ T26] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.226728][ T26] ? trace_hardirqs_on+0x55/0x220 [ 62.231745][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.237290][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.242913][ T26] ? afs_put_call+0xa40/0xa40 [ 62.247608][ T26] end_report+0x4d/0x53 [ 62.251755][ T26] kasan_report.cold+0xd/0x37 [ 62.256434][ T26] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.262597][ T26] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.268141][ T26] afs_wake_up_async_call+0x6aa/0x770 [ 62.273520][ T26] ? afs_close_socket+0x320/0x320 [ 62.278547][ T26] ? afs_put_call+0xa40/0xa40 [ 62.283219][ T26] rxrpc_notify_socket+0x1db/0x5d0 [ 62.288338][ T26] ? afs_put_call+0xa40/0xa40 [ 62.293013][ T26] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.299423][ T26] rxrpc_call_completed+0xca/0xf0 [ 62.304444][ T26] rxrpc_discard_prealloc+0x781/0xab0 [ 62.309829][ T26] ? lock_sock_nested+0x94/0x110 [ 62.314762][ T26] rxrpc_listen+0x147/0x360 [ 62.319337][ T26] afs_close_socket+0x95/0x320 [ 62.324099][ T26] ? afs_purge_servers+0x16d/0x300 [ 62.329203][ T26] ? afs_rx_discard_new_call+0x50/0x50 [ 62.334658][ T26] ? init_wait_var_entry+0x200/0x200 [ 62.339945][ T26] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.345577][ T26] ? check_preemption_disabled+0x38/0x220 [ 62.351289][ T26] afs_net_exit+0x1bc/0x310 [ 62.355788][ T26] ? afs_net_init+0xe30/0xe30 [ 62.360454][ T26] ops_exit_list.isra.0+0xa8/0x150 [ 62.365556][ T26] cleanup_net+0x511/0xa50 [ 62.370140][ T26] ? unregister_pernet_device+0x70/0x70 [ 62.375679][ T26] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.381652][ T26] process_one_work+0x965/0x1690 [ 62.386680][ T26] ? lock_release+0x800/0x800 [ 62.391353][ T26] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.396717][ T26] ? rwlock_bug.part.0+0x90/0x90 [ 62.401649][ T26] worker_thread+0x96/0xe10 [ 62.406153][ T26] ? process_one_work+0x1690/0x1690 [ 62.411340][ T26] kthread+0x3b5/0x4a0 [ 62.415403][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.421741][ T26] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.427549][ T26] ret_from_fork+0x1f/0x30 [ 62.433640][ T26] Kernel Offset: disabled [ 62.437985][ T26] Rebooting in 86400 seconds..