[ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ 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... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.88' (ECDSA) to the list of known hosts. 2020/06/19 00:46:34 fuzzer started 2020/06/19 00:46:34 connecting to host at 10.128.0.26:40207 2020/06/19 00:46:34 checking machine... 2020/06/19 00:46:34 checking revisions... 2020/06/19 00:46:34 testing simple program... syzkaller login: [ 63.197869][ T6900] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 00:46:35 building call list... [ 63.551733][ T509] tipc: TX() has been purged, node left! [ 64.054142][ T509] ================================================================== [ 64.062402][ T509] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 64.070330][ T509] Write of size 1 at addr ffff8880962501e4 by task kworker/u4:10/509 [ 64.078486][ T509] [ 64.080824][ T509] CPU: 1 PID: 509 Comm: kworker/u4:10 Not tainted 5.8.0-rc1-syzkaller #0 [ 64.089405][ T509] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.099468][ T509] Workqueue: netns cleanup_net [ 64.104330][ T509] Call Trace: [ 64.108558][ T509] dump_stack+0x18f/0x20d [ 64.112911][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.118467][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.124284][ T509] ? afs_put_call+0xa40/0xa40 [ 64.129167][ T509] print_address_description.constprop.0.cold+0xd3/0x413 [ 64.136517][ T509] ? vprintk_func+0x97/0x1a6 [ 64.141117][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.147113][ T509] kasan_report.cold+0x1f/0x37 [ 64.152460][ T509] ? rcu_read_lock_held_common+0x51/0xa0 [ 64.158097][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.164011][ T509] afs_wake_up_async_call+0x6aa/0x770 [ 64.169470][ T509] ? afs_close_socket+0x320/0x320 [ 64.174779][ T509] ? afs_put_call+0xa40/0xa40 [ 64.180242][ T509] rxrpc_notify_socket+0x1db/0x5d0 [ 64.185747][ T509] ? afs_put_call+0xa40/0xa40 [ 64.190611][ T509] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 64.198400][ T509] rxrpc_call_completed+0xca/0xf0 [ 64.204062][ T509] rxrpc_discard_prealloc+0x781/0xab0 [ 64.210238][ T509] ? lock_sock_nested+0x94/0x110 [ 64.215632][ T509] rxrpc_listen+0x147/0x360 [ 64.220659][ T509] afs_close_socket+0x95/0x320 [ 64.226502][ T509] ? afs_purge_servers+0x16d/0x300 [ 64.233507][ T509] ? afs_rx_discard_new_call+0x50/0x50 [ 64.239263][ T509] ? init_wait_var_entry+0x200/0x200 [ 64.244657][ T509] ? rcu_read_lock_held_common+0xa0/0xa0 [ 64.252477][ T509] ? check_preemption_disabled+0x38/0x220 [ 64.260681][ T509] afs_net_exit+0x1bc/0x310 [ 64.266763][ T509] ? afs_net_init+0xe30/0xe30 [ 64.275803][ T509] ops_exit_list.isra.0+0xa8/0x150 [ 64.281013][ T509] cleanup_net+0x511/0xa50 [ 64.285531][ T509] ? unregister_pernet_device+0x70/0x70 [ 64.291308][ T509] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 64.297341][ T509] process_one_work+0x965/0x1690 [ 64.302936][ T509] ? lock_release+0x800/0x800 [ 64.308104][ T509] ? pwq_dec_nr_in_flight+0x310/0x310 [ 64.313491][ T509] ? rwlock_bug.part.0+0x90/0x90 [ 64.320246][ T509] worker_thread+0x96/0xe10 [ 64.324787][ T509] ? process_one_work+0x1690/0x1690 [ 64.330116][ T509] kthread+0x3b5/0x4a0 [ 64.335070][ T509] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.342169][ T509] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.347994][ T509] ret_from_fork+0x1f/0x30 [ 64.352422][ T509] [ 64.354835][ T509] Allocated by task 6900: [ 64.359427][ T509] save_stack+0x1b/0x40 [ 64.363892][ T509] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 64.369760][ T509] kmem_cache_alloc_trace+0x153/0x7d0 [ 64.375332][ T509] afs_alloc_call+0x55/0x630 [ 64.380050][ T509] afs_charge_preallocation+0xe9/0x2d0 [ 64.385770][ T509] afs_open_socket+0x292/0x360 [ 64.390530][ T509] afs_net_init+0xa6c/0xe30 [ 64.395056][ T509] ops_init+0xaf/0x420 [ 64.399444][ T509] setup_net+0x2de/0x860 [ 64.403871][ T509] copy_net_ns+0x293/0x590 [ 64.408398][ T509] create_new_namespaces+0x3fb/0xb30 [ 64.413826][ T509] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 64.419498][ T509] ksys_unshare+0x43d/0x8e0 [ 64.424034][ T509] __x64_sys_unshare+0x2d/0x40 [ 64.428915][ T509] do_syscall_64+0x60/0xe0 [ 64.433714][ T509] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 64.439638][ T509] [ 64.441978][ T509] Freed by task 509: [ 64.446109][ T509] save_stack+0x1b/0x40 [ 64.450528][ T509] __kasan_slab_free+0xf7/0x140 [ 64.456285][ T509] kfree+0x109/0x2b0 [ 64.460288][ T509] afs_put_call+0x585/0xa40 [ 64.464917][ T509] rxrpc_discard_prealloc+0x764/0xab0 [ 64.470497][ T509] rxrpc_listen+0x147/0x360 [ 64.475975][ T509] afs_close_socket+0x95/0x320 [ 64.480824][ T509] afs_net_exit+0x1bc/0x310 [ 64.485448][ T509] ops_exit_list.isra.0+0xa8/0x150 [ 64.490649][ T509] cleanup_net+0x511/0xa50 [ 64.495270][ T509] process_one_work+0x965/0x1690 [ 64.500354][ T509] worker_thread+0x96/0xe10 [ 64.504956][ T509] kthread+0x3b5/0x4a0 [ 64.509134][ T509] ret_from_fork+0x1f/0x30 [ 64.513547][ T509] [ 64.515879][ T509] The buggy address belongs to the object at ffff888096250000 [ 64.515879][ T509] which belongs to the cache kmalloc-1k of size 1024 [ 64.530442][ T509] The buggy address is located 484 bytes inside of [ 64.530442][ T509] 1024-byte region [ffff888096250000, ffff888096250400) [ 64.544072][ T509] The buggy address belongs to the page: [ 64.550502][ T509] page:ffffea0002589400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 64.559706][ T509] flags: 0xfffe0000000200(slab) [ 64.564566][ T509] raw: 00fffe0000000200 ffffea000258de88 ffffea0002589448 ffff8880aa000c40 [ 64.573364][ T509] raw: 0000000000000000 ffff888096250000 0000000100000002 0000000000000000 [ 64.582044][ T509] page dumped because: kasan: bad access detected [ 64.588774][ T509] [ 64.591107][ T509] Memory state around the buggy address: [ 64.597712][ T509] ffff888096250080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.605970][ T509] ffff888096250100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.614039][ T509] >ffff888096250180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.622363][ T509] ^ [ 64.629578][ T509] ffff888096250200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.637652][ T509] ffff888096250280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.646067][ T509] ================================================================== [ 64.658496][ T509] Disabling lock debugging due to kernel taint [ 64.664702][ T509] Kernel panic - not syncing: panic_on_warn set ... [ 64.671369][ T509] CPU: 1 PID: 509 Comm: kworker/u4:10 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 64.681442][ T509] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.691525][ T509] Workqueue: netns cleanup_net [ 64.696280][ T509] Call Trace: [ 64.699579][ T509] dump_stack+0x18f/0x20d [ 64.704009][ T509] ? afs_wake_up_async_call+0x670/0x770 [ 64.709555][ T509] ? afs_put_call+0xa40/0xa40 [ 64.714243][ T509] panic+0x2e3/0x75c [ 64.718245][ T509] ? __warn_printk+0xf3/0xf3 [ 64.723798][ T509] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 64.729955][ T509] ? trace_hardirqs_on+0x55/0x220 [ 64.734980][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.740619][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.746247][ T509] ? afs_put_call+0xa40/0xa40 [ 64.750960][ T509] end_report+0x4d/0x53 [ 64.755115][ T509] kasan_report.cold+0xd/0x37 [ 64.759793][ T509] ? rcu_read_lock_held_common+0x51/0xa0 [ 64.765441][ T509] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.771088][ T509] afs_wake_up_async_call+0x6aa/0x770 [ 64.776547][ T509] ? afs_close_socket+0x320/0x320 [ 64.781656][ T509] ? afs_put_call+0xa40/0xa40 [ 64.786909][ T509] rxrpc_notify_socket+0x1db/0x5d0 [ 64.792488][ T509] ? afs_put_call+0xa40/0xa40 [ 64.797222][ T509] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 64.803814][ T509] rxrpc_call_completed+0xca/0xf0 [ 64.809147][ T509] rxrpc_discard_prealloc+0x781/0xab0 [ 64.814543][ T509] ? lock_sock_nested+0x94/0x110 [ 64.819479][ T509] rxrpc_listen+0x147/0x360 [ 64.825119][ T509] afs_close_socket+0x95/0x320 [ 64.829979][ T509] ? afs_purge_servers+0x16d/0x300 [ 64.835094][ T509] ? afs_rx_discard_new_call+0x50/0x50 [ 64.840555][ T509] ? init_wait_var_entry+0x200/0x200 [ 64.845964][ T509] ? rcu_read_lock_held_common+0xa0/0xa0 [ 64.851597][ T509] ? check_preemption_disabled+0x38/0x220 [ 64.857512][ T509] afs_net_exit+0x1bc/0x310 [ 64.862307][ T509] ? afs_net_init+0xe30/0xe30 [ 64.867074][ T509] ops_exit_list.isra.0+0xa8/0x150 [ 64.872326][ T509] cleanup_net+0x511/0xa50 [ 64.876771][ T509] ? unregister_pernet_device+0x70/0x70 [ 64.882357][ T509] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 64.888347][ T509] process_one_work+0x965/0x1690 [ 64.893294][ T509] ? lock_release+0x800/0x800 [ 64.898130][ T509] ? pwq_dec_nr_in_flight+0x310/0x310 [ 64.903598][ T509] ? rwlock_bug.part.0+0x90/0x90 [ 64.909691][ T509] worker_thread+0x96/0xe10 [ 64.914289][ T509] ? process_one_work+0x1690/0x1690 [ 64.919594][ T509] kthread+0x3b5/0x4a0 [ 64.923667][ T509] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.929380][ T509] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.935242][ T509] ret_from_fork+0x1f/0x30 [ 64.942639][ T509] Kernel Offset: disabled [ 64.947920][ T509] Rebooting in 86400 seconds..