[ 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... [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.29' (ECDSA) to the list of known hosts. 2020/06/14 23:21:27 fuzzer started 2020/06/14 23:21:27 connecting to host at 10.128.0.26:38721 2020/06/14 23:21:27 checking machine... 2020/06/14 23:21:27 checking revisions... 2020/06/14 23:21:27 testing simple program... syzkaller login: [ 58.725440][ T6856] IPVS: ftp: loaded support on port[0] = 21 2020/06/14 23:21:28 building call list... [ 59.071850][ T21] tipc: TX() has been purged, node left! [ 59.563960][ T21] ================================================================== [ 59.572224][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 59.580108][ T21] Write of size 1 at addr ffff8880a86049e4 by task kworker/u4:1/21 [ 59.587984][ T21] [ 59.590317][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.7.0-next-20200614-syzkaller #0 [ 59.599423][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.609485][ T21] Workqueue: netns cleanup_net [ 59.614412][ T21] Call Trace: [ 59.617707][ T21] dump_stack+0x18f/0x20d [ 59.622040][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 59.627580][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 59.633125][ T21] ? afs_put_call+0xa40/0xa40 [ 59.637805][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 59.644830][ T21] ? vprintk_func+0x97/0x1a6 [ 59.649429][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 59.654971][ T21] kasan_report.cold+0x1f/0x37 [ 59.659738][ T21] ? rcu_read_lock_held_common+0x41/0xa0 [ 59.665371][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 59.670924][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 59.676293][ T21] ? afs_close_socket+0x320/0x320 [ 59.681314][ T21] ? afs_put_call+0xa40/0xa40 [ 59.685987][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 59.691102][ T21] ? afs_put_call+0xa40/0xa40 [ 59.695791][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 59.702236][ T21] rxrpc_call_completed+0xca/0xf0 [ 59.707268][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 59.712643][ T21] ? lock_sock_nested+0x94/0x110 [ 59.717599][ T21] rxrpc_listen+0x147/0x360 [ 59.722246][ T21] afs_close_socket+0x95/0x320 [ 59.727025][ T21] ? afs_purge_servers+0x16d/0x300 [ 59.732140][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 59.737610][ T21] ? init_wait_var_entry+0x200/0x200 [ 59.742898][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 59.748534][ T21] ? check_preemption_disabled+0x38/0x220 [ 59.754257][ T21] afs_net_exit+0x1bc/0x310 [ 59.758761][ T21] ? afs_net_init+0xe30/0xe30 [ 59.763434][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 59.768548][ T21] cleanup_net+0x511/0xa50 [ 59.772965][ T21] ? unregister_pernet_device+0x70/0x70 [ 59.778514][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 59.784506][ T21] process_one_work+0x965/0x1690 [ 59.789459][ T21] ? lock_release+0x800/0x800 [ 59.794140][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 59.799536][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 59.804508][ T21] worker_thread+0x96/0xe10 [ 59.809076][ T21] ? process_one_work+0x1690/0x1690 [ 59.814331][ T21] kthread+0x3b5/0x4a0 [ 59.818428][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 59.824185][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 59.829916][ T21] ret_from_fork+0x1f/0x30 [ 59.834347][ T21] [ 59.836669][ T21] Allocated by task 6856: [ 59.840998][ T21] save_stack+0x1b/0x40 [ 59.845148][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 59.850777][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 59.856153][ T21] afs_alloc_call+0x55/0x630 [ 59.860738][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 59.866189][ T21] afs_open_socket+0x292/0x360 [ 59.870947][ T21] afs_net_init+0xa6c/0xe30 [ 59.875449][ T21] ops_init+0xaf/0x420 [ 59.879511][ T21] setup_net+0x2de/0x860 [ 59.883763][ T21] copy_net_ns+0x293/0x590 [ 59.888186][ T21] create_new_namespaces+0x3fb/0xb30 [ 59.893473][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 59.899104][ T21] ksys_unshare+0x43d/0x8e0 [ 59.903605][ T21] __x64_sys_unshare+0x2d/0x40 [ 59.908368][ T21] do_syscall_64+0x60/0xe0 [ 59.912783][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 59.918835][ T21] [ 59.921159][ T21] Freed by task 21: [ 59.924965][ T21] save_stack+0x1b/0x40 [ 59.929114][ T21] __kasan_slab_free+0xf7/0x140 [ 59.933959][ T21] kfree+0x109/0x2b0 [ 59.937851][ T21] afs_put_call+0x585/0xa40 [ 59.942351][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 59.947749][ T21] rxrpc_listen+0x147/0x360 [ 59.952248][ T21] afs_close_socket+0x95/0x320 [ 59.957010][ T21] afs_net_exit+0x1bc/0x310 [ 59.961509][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 59.966615][ T21] cleanup_net+0x511/0xa50 [ 59.971037][ T21] process_one_work+0x965/0x1690 [ 59.975970][ T21] worker_thread+0x96/0xe10 [ 59.980496][ T21] kthread+0x3b5/0x4a0 [ 59.984560][ T21] ret_from_fork+0x1f/0x30 [ 59.988962][ T21] [ 59.991290][ T21] The buggy address belongs to the object at ffff8880a8604800 [ 59.991290][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 60.005349][ T21] The buggy address is located 484 bytes inside of [ 60.005349][ T21] 1024-byte region [ffff8880a8604800, ffff8880a8604c00) [ 60.018703][ T21] The buggy address belongs to the page: [ 60.024335][ T21] page:ffffea0002a18100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 60.033433][ T21] flags: 0xfffe0000000200(slab) [ 60.038288][ T21] raw: 00fffe0000000200 ffffea00028e9e08 ffffea00029bce08 ffff8880aa000c40 [ 60.046880][ T21] raw: 0000000000000000 ffff8880a8604000 0000000100000002 0000000000000000 [ 60.055463][ T21] page dumped because: kasan: bad access detected [ 60.061868][ T21] [ 60.064189][ T21] Memory state around the buggy address: [ 60.069827][ T21] ffff8880a8604880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.077896][ T21] ffff8880a8604900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.085967][ T21] >ffff8880a8604980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.095079][ T21] ^ [ 60.102792][ T21] ffff8880a8604a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.110938][ T21] ffff8880a8604a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.119474][ T21] ================================================================== [ 60.127527][ T21] Disabling lock debugging due to kernel taint [ 60.133732][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 60.140317][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.7.0-next-20200614-syzkaller #0 [ 60.150802][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.160862][ T21] Workqueue: netns cleanup_net [ 60.165614][ T21] Call Trace: [ 60.168898][ T21] dump_stack+0x18f/0x20d [ 60.173220][ T21] ? afs_wake_up_async_call+0x5e0/0x770 [ 60.178752][ T21] ? afs_put_call+0xa40/0xa40 [ 60.183419][ T21] panic+0x2e3/0x75c [ 60.187322][ T21] ? __warn_printk+0xf3/0xf3 [ 60.191900][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 60.198220][ T21] ? trace_hardirqs_on+0x55/0x220 [ 60.203239][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.208780][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.214401][ T21] ? afs_put_call+0xa40/0xa40 [ 60.219069][ T21] end_report+0x4d/0x53 [ 60.223221][ T21] kasan_report.cold+0xd/0x37 [ 60.227987][ T21] ? rcu_read_lock_held_common+0x41/0xa0 [ 60.233727][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.240397][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 60.245756][ T21] ? afs_close_socket+0x320/0x320 [ 60.250772][ T21] ? afs_put_call+0xa40/0xa40 [ 60.255434][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 60.260565][ T21] ? afs_put_call+0xa40/0xa40 [ 60.265229][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.271652][ T21] rxrpc_call_completed+0xca/0xf0 [ 60.276668][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 60.282037][ T21] ? lock_sock_nested+0x94/0x110 [ 60.286972][ T21] rxrpc_listen+0x147/0x360 [ 60.291497][ T21] afs_close_socket+0x95/0x320 [ 60.296249][ T21] ? afs_purge_servers+0x16d/0x300 [ 60.301347][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 60.306796][ T21] ? init_wait_var_entry+0x200/0x200 [ 60.312078][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 60.317733][ T21] ? check_preemption_disabled+0x38/0x220 [ 60.323526][ T21] afs_net_exit+0x1bc/0x310 [ 60.328029][ T21] ? afs_net_init+0xe30/0xe30 [ 60.332713][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 60.337820][ T21] cleanup_net+0x511/0xa50 [ 60.342234][ T21] ? unregister_pernet_device+0x70/0x70 [ 60.347805][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.353790][ T21] process_one_work+0x965/0x1690 [ 60.358737][ T21] ? lock_release+0x800/0x800 [ 60.363503][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 60.368875][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 60.373815][ T21] worker_thread+0x96/0xe10 [ 60.378351][ T21] ? process_one_work+0x1690/0x1690 [ 60.383559][ T21] kthread+0x3b5/0x4a0 [ 60.387637][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.393359][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.399082][ T21] ret_from_fork+0x1f/0x30 [ 60.405179][ T21] Kernel Offset: disabled [ 60.409506][ T21] Rebooting in 86400 seconds..