[ 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 '10.128.0.195' (ECDSA) to the list of known hosts. 2020/07/01 10:52:57 fuzzer started 2020/07/01 10:52:57 connecting to host at 10.128.0.26:39285 2020/07/01 10:52:57 checking machine... 2020/07/01 10:52:57 checking revisions... 2020/07/01 10:52:57 testing simple program... syzkaller login: [ 58.387051][ T6850] IPVS: ftp: loaded support on port[0] = 21 2020/07/01 10:52:57 building call list... [ 58.727003][ T42] tipc: TX() has been purged, node left! [ 59.222676][ T42] ================================================================== [ 59.230894][ T42] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 59.238775][ T42] Write of size 1 at addr ffff888081ec19e4 by task kworker/u4:2/42 [ 59.246645][ T42] [ 59.248975][ T42] CPU: 0 PID: 42 Comm: kworker/u4:2 Not tainted 5.8.0-rc1-syzkaller #0 [ 59.257197][ T42] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.267248][ T42] Workqueue: netns cleanup_net [ 59.272003][ T42] Call Trace: [ 59.275290][ T42] dump_stack+0x18f/0x20d [ 59.279619][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.285155][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.290691][ T42] ? afs_put_call+0x440/0x440 [ 59.295364][ T42] print_address_description.constprop.0.cold+0xae/0x436 [ 59.302389][ T42] ? vprintk_func+0x97/0x1a6 [ 59.306981][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.312519][ T42] kasan_report.cold+0x1f/0x37 [ 59.317284][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.322829][ T42] afs_wake_up_async_call+0x430/0x4a0 [ 59.328193][ T42] ? afs_close_socket+0x320/0x320 [ 59.333215][ T42] rxrpc_notify_socket+0x1db/0x5d0 [ 59.338329][ T42] ? afs_put_call+0x440/0x440 [ 59.343002][ T42] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 59.349415][ T42] rxrpc_call_completed+0xd0/0xf0 [ 59.354436][ T42] rxrpc_discard_prealloc+0x777/0xab0 [ 59.359804][ T42] ? lock_sock_nested+0x94/0x110 [ 59.364743][ T42] rxrpc_listen+0x11c/0x330 [ 59.369250][ T42] afs_close_socket+0x95/0x320 [ 59.374006][ T42] ? afs_purge_servers+0x16d/0x300 [ 59.379113][ T42] ? afs_rx_discard_new_call+0x50/0x50 [ 59.384571][ T42] ? init_wait_var_entry+0x200/0x200 [ 59.389856][ T42] ? check_preemption_disabled+0x38/0x220 [ 59.395572][ T42] afs_net_exit+0x1bc/0x310 [ 59.400069][ T42] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 59.405694][ T42] ops_exit_list+0xb0/0x160 [ 59.410197][ T42] cleanup_net+0x4ea/0xa00 [ 59.414609][ T42] ? __schedule+0x887/0x1eb0 [ 59.419194][ T42] ? ops_free_list.part.0+0x3d0/0x3d0 [ 59.424651][ T42] ? check_preemption_disabled+0x38/0x220 [ 59.430375][ T42] process_one_work+0x94c/0x1670 [ 59.435319][ T42] ? lock_release+0x8d0/0x8d0 [ 59.439994][ T42] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 59.445367][ T42] ? rwlock_bug.part.0+0x90/0x90 [ 59.450310][ T42] worker_thread+0x64c/0x1120 [ 59.454997][ T42] ? __kthread_parkme+0x13f/0x1e0 [ 59.460014][ T42] ? process_one_work+0x1670/0x1670 [ 59.465210][ T42] kthread+0x3b5/0x4a0 [ 59.469273][ T42] ? __kthread_bind_mask+0xc0/0xc0 [ 59.474373][ T42] ? __kthread_bind_mask+0xc0/0xc0 [ 59.479481][ T42] ret_from_fork+0x1f/0x30 [ 59.483910][ T42] [ 59.486228][ T42] Allocated by task 6850: [ 59.490556][ T42] save_stack+0x1b/0x40 [ 59.494709][ T42] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 59.500332][ T42] kmem_cache_alloc_trace+0x14f/0x2d0 [ 59.505693][ T42] afs_alloc_call+0x4f/0x360 [ 59.510273][ T42] afs_charge_preallocation+0xe9/0x2d0 [ 59.515722][ T42] afs_open_socket+0x294/0x360 [ 59.520478][ T42] afs_net_init+0xa6c/0xe30 [ 59.524971][ T42] ops_init+0xaf/0x470 [ 59.529032][ T42] setup_net+0x2d8/0x850 [ 59.533265][ T42] copy_net_ns+0x2cf/0x5e0 [ 59.537671][ T42] create_new_namespaces+0x3f6/0xb10 [ 59.542946][ T42] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 59.548571][ T42] ksys_unshare+0x36c/0x9a0 [ 59.553069][ T42] __x64_sys_unshare+0x2d/0x40 [ 59.557833][ T42] do_syscall_64+0x60/0xe0 [ 59.562255][ T42] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 59.568132][ T42] [ 59.570449][ T42] Freed by task 42: [ 59.574255][ T42] save_stack+0x1b/0x40 [ 59.578402][ T42] __kasan_slab_free+0xf5/0x140 [ 59.583251][ T42] kfree+0x103/0x2c0 [ 59.587137][ T42] afs_put_call+0x345/0x440 [ 59.591631][ T42] rxrpc_discard_prealloc+0x75a/0xab0 [ 59.596996][ T42] rxrpc_listen+0x11c/0x330 [ 59.601492][ T42] afs_close_socket+0x95/0x320 [ 59.606249][ T42] afs_net_exit+0x1bc/0x310 [ 59.610741][ T42] ops_exit_list+0xb0/0x160 [ 59.615242][ T42] cleanup_net+0x4ea/0xa00 [ 59.619653][ T42] process_one_work+0x94c/0x1670 [ 59.624586][ T42] worker_thread+0x64c/0x1120 [ 59.629252][ T42] kthread+0x3b5/0x4a0 [ 59.633321][ T42] ret_from_fork+0x1f/0x30 [ 59.637718][ T42] [ 59.640043][ T42] The buggy address belongs to the object at ffff888081ec1800 [ 59.640043][ T42] which belongs to the cache kmalloc-1k of size 1024 [ 59.654092][ T42] The buggy address is located 484 bytes inside of [ 59.654092][ T42] 1024-byte region [ffff888081ec1800, ffff888081ec1c00) [ 59.667434][ T42] The buggy address belongs to the page: [ 59.673063][ T42] page:ffffea000207b040 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 59.682156][ T42] flags: 0xfffe0000000200(slab) [ 59.687003][ T42] raw: 00fffe0000000200 ffffea000207b008 ffffea000207b088 ffff8880aa000c40 [ 59.695583][ T42] raw: 0000000000000000 ffff888081ec1000 0000000100000002 0000000000000000 [ 59.704156][ T42] page dumped because: kasan: bad access detected [ 59.710563][ T42] [ 59.712892][ T42] Memory state around the buggy address: [ 59.718522][ T42] ffff888081ec1880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.726578][ T42] ffff888081ec1900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.734632][ T42] >ffff888081ec1980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.742678][ T42] ^ [ 59.749862][ T42] ffff888081ec1a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.757913][ T42] ffff888081ec1a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.765968][ T42] ================================================================== [ 59.774032][ T42] Disabling lock debugging due to kernel taint [ 59.780221][ T42] Kernel panic - not syncing: panic_on_warn set ... [ 59.786802][ T42] CPU: 0 PID: 42 Comm: kworker/u4:2 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 59.796411][ T42] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.806474][ T42] Workqueue: netns cleanup_net [ 59.811228][ T42] Call Trace: [ 59.814515][ T42] dump_stack+0x18f/0x20d [ 59.818843][ T42] ? afs_wake_up_async_call+0x400/0x4a0 [ 59.824382][ T42] ? afs_put_call+0x440/0x440 [ 59.829046][ T42] panic+0x2e3/0x75c [ 59.832923][ T42] ? __warn_printk+0xf3/0xf3 [ 59.837503][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.843041][ T42] ? trace_hardirqs_on+0x55/0x220 [ 59.848056][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.853582][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.859223][ T42] ? afs_put_call+0x440/0x440 [ 59.863890][ T42] end_report+0x4d/0x53 [ 59.868038][ T42] kasan_report.cold+0xd/0x37 [ 59.872707][ T42] ? afs_wake_up_async_call+0x430/0x4a0 [ 59.878242][ T42] afs_wake_up_async_call+0x430/0x4a0 [ 59.883602][ T42] ? afs_close_socket+0x320/0x320 [ 59.888620][ T42] rxrpc_notify_socket+0x1db/0x5d0 [ 59.893727][ T42] ? afs_put_call+0x440/0x440 [ 59.898395][ T42] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 59.904801][ T42] rxrpc_call_completed+0xd0/0xf0 [ 59.909814][ T42] rxrpc_discard_prealloc+0x777/0xab0 [ 59.915172][ T42] ? lock_sock_nested+0x94/0x110 [ 59.920102][ T42] rxrpc_listen+0x11c/0x330 [ 59.924593][ T42] afs_close_socket+0x95/0x320 [ 59.929343][ T42] ? afs_purge_servers+0x16d/0x300 [ 59.934446][ T42] ? afs_rx_discard_new_call+0x50/0x50 [ 59.939897][ T42] ? init_wait_var_entry+0x200/0x200 [ 59.945176][ T42] ? check_preemption_disabled+0x38/0x220 [ 59.950885][ T42] afs_net_exit+0x1bc/0x310 [ 59.955384][ T42] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 59.961005][ T42] ops_exit_list+0xb0/0x160 [ 59.965501][ T42] cleanup_net+0x4ea/0xa00 [ 59.969907][ T42] ? __schedule+0x887/0x1eb0 [ 59.974486][ T42] ? ops_free_list.part.0+0x3d0/0x3d0 [ 59.979851][ T42] ? check_preemption_disabled+0x38/0x220 [ 59.985564][ T42] process_one_work+0x94c/0x1670 [ 59.990495][ T42] ? lock_release+0x8d0/0x8d0 [ 59.995162][ T42] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 60.000530][ T42] ? rwlock_bug.part.0+0x90/0x90 [ 60.005459][ T42] worker_thread+0x64c/0x1120 [ 60.010148][ T42] ? __kthread_parkme+0x13f/0x1e0 [ 60.015164][ T42] ? process_one_work+0x1670/0x1670 [ 60.020355][ T42] kthread+0x3b5/0x4a0 [ 60.024412][ T42] ? __kthread_bind_mask+0xc0/0xc0 [ 60.029510][ T42] ? __kthread_bind_mask+0xc0/0xc0 [ 60.034614][ T42] ret_from_fork+0x1f/0x30 [ 60.040168][ T42] Kernel Offset: disabled [ 60.044498][ T42] Rebooting in 86400 seconds..