[ 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 '10.128.0.148' (ECDSA) to the list of known hosts. 2020/06/25 20:51:42 fuzzer started 2020/06/25 20:51:42 connecting to host at 10.128.0.26:40341 2020/06/25 20:51:42 checking machine... 2020/06/25 20:51:42 checking revisions... 2020/06/25 20:51:42 testing simple program... syzkaller login: [ 60.339772][ T6817] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 20:51:42 building call list... [ 60.629530][ T203] tipc: TX() has been purged, node left! [ 61.151542][ T203] ================================================================== [ 61.159972][ T203] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 61.167859][ T203] Write of size 1 at addr ffff8880a919a9e4 by task kworker/u4:4/203 [ 61.175818][ T203] [ 61.178158][ T203] CPU: 1 PID: 203 Comm: kworker/u4:4 Not tainted 5.8.0-rc2-syzkaller #0 [ 61.186496][ T203] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.196670][ T203] Workqueue: netns cleanup_net [ 61.201423][ T203] Call Trace: [ 61.204714][ T203] dump_stack+0x18f/0x20d [ 61.209138][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.214680][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.220659][ T203] ? afs_put_call+0x440/0x440 [ 61.225336][ T203] print_address_description.constprop.0.cold+0xae/0x436 [ 61.232365][ T203] ? vprintk_func+0x97/0x1a6 [ 61.237007][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.242569][ T203] kasan_report.cold+0x1f/0x37 [ 61.247422][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.252969][ T203] afs_wake_up_async_call+0x430/0x4a0 [ 61.258335][ T203] ? afs_close_socket+0x320/0x320 [ 61.263364][ T203] rxrpc_notify_socket+0x1db/0x5d0 [ 61.268476][ T203] ? afs_put_call+0x440/0x440 [ 61.274368][ T203] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.280788][ T203] rxrpc_call_completed+0xd0/0xf0 [ 61.285832][ T203] rxrpc_discard_prealloc+0x777/0xab0 [ 61.291215][ T203] ? lock_sock_nested+0x94/0x110 [ 61.296463][ T203] rxrpc_listen+0x11c/0x330 [ 61.300967][ T203] afs_close_socket+0x95/0x320 [ 61.305757][ T203] ? afs_purge_servers+0x181/0x330 [ 61.310879][ T203] ? afs_rx_discard_new_call+0x50/0x50 [ 61.316772][ T203] ? init_wait_var_entry+0x200/0x200 [ 61.322066][ T203] afs_net_exit+0x1c4/0x310 [ 61.326740][ T203] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.332370][ T203] ops_exit_list+0xb0/0x160 [ 61.336879][ T203] cleanup_net+0x4ea/0xa00 [ 61.341292][ T203] ? __schedule+0x887/0x1eb0 [ 61.345885][ T203] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.351356][ T203] ? check_preemption_disabled+0x38/0x220 [ 61.357084][ T203] process_one_work+0x94c/0x1670 [ 61.362055][ T203] ? lock_release+0x8d0/0x8d0 [ 61.366747][ T203] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.372127][ T203] ? rwlock_bug.part.0+0x90/0x90 [ 61.377512][ T203] worker_thread+0x64c/0x1120 [ 61.382543][ T203] ? __kthread_parkme+0x13f/0x1e0 [ 61.387567][ T203] ? process_one_work+0x1670/0x1670 [ 61.392764][ T203] kthread+0x3b5/0x4a0 [ 61.396827][ T203] ? __kthread_bind_mask+0xc0/0xc0 [ 61.401952][ T203] ? __kthread_bind_mask+0xc0/0xc0 [ 61.407064][ T203] ret_from_fork+0x1f/0x30 [ 61.411503][ T203] [ 61.413829][ T203] Allocated by task 6817: [ 61.418156][ T203] save_stack+0x1b/0x40 [ 61.422309][ T203] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 61.427936][ T203] kmem_cache_alloc_trace+0x14f/0x2d0 [ 61.433303][ T203] afs_alloc_call+0x4f/0x360 [ 61.437888][ T203] afs_charge_preallocation+0xe9/0x2d0 [ 61.443337][ T203] afs_open_socket+0x294/0x360 [ 61.448094][ T203] afs_net_init+0xab4/0xe90 [ 61.452683][ T203] ops_init+0xaf/0x470 [ 61.456744][ T203] setup_net+0x2d8/0x850 [ 61.460978][ T203] copy_net_ns+0x2cf/0x5e0 [ 61.465415][ T203] create_new_namespaces+0x3f6/0xb10 [ 61.470694][ T203] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.476341][ T203] ksys_unshare+0x36c/0x9a0 [ 61.480855][ T203] __ia32_sys_unshare+0x2c/0x40 [ 61.485703][ T203] do_syscall_32_irqs_on+0x3f/0x60 [ 61.490855][ T203] do_fast_syscall_32+0x7f/0x120 [ 61.495789][ T203] entry_SYSENTER_compat+0x6d/0x7c [ 61.500895][ T203] [ 61.503216][ T203] Freed by task 203: [ 61.507112][ T203] save_stack+0x1b/0x40 [ 61.511263][ T203] __kasan_slab_free+0xf5/0x140 [ 61.516110][ T203] kfree+0x103/0x2c0 [ 61.520001][ T203] afs_put_call+0x345/0x440 [ 61.524591][ T203] rxrpc_discard_prealloc+0x75a/0xab0 [ 61.529956][ T203] rxrpc_listen+0x11c/0x330 [ 61.534473][ T203] afs_close_socket+0x95/0x320 [ 61.539322][ T203] afs_net_exit+0x1c4/0x310 [ 61.543899][ T203] ops_exit_list+0xb0/0x160 [ 61.548406][ T203] cleanup_net+0x4ea/0xa00 [ 61.552816][ T203] process_one_work+0x94c/0x1670 [ 61.557748][ T203] worker_thread+0x64c/0x1120 [ 61.562598][ T203] kthread+0x3b5/0x4a0 [ 61.566689][ T203] ret_from_fork+0x1f/0x30 [ 61.571097][ T203] [ 61.573421][ T203] The buggy address belongs to the object at ffff8880a919a800 [ 61.573421][ T203] which belongs to the cache kmalloc-1k of size 1024 [ 61.587566][ T203] The buggy address is located 484 bytes inside of [ 61.587566][ T203] 1024-byte region [ffff8880a919a800, ffff8880a919ac00) [ 61.600928][ T203] The buggy address belongs to the page: [ 61.606571][ T203] page:ffffea0002a46680 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.615671][ T203] flags: 0xfffe0000000200(slab) [ 61.620521][ T203] raw: 00fffe0000000200 ffffea00029f6308 ffffea00025bec08 ffff8880aa000c40 [ 61.629191][ T203] raw: 0000000000000000 ffff8880a919a000 0000000100000002 0000000000000000 [ 61.637778][ T203] page dumped because: kasan: bad access detected [ 61.644185][ T203] [ 61.646503][ T203] Memory state around the buggy address: [ 61.652131][ T203] ffff8880a919a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.661184][ T203] ffff8880a919a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.669504][ T203] >ffff8880a919a980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.677704][ T203] ^ [ 61.684901][ T203] ffff8880a919aa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.693167][ T203] ffff8880a919aa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.701578][ T203] ================================================================== [ 61.709634][ T203] Disabling lock debugging due to kernel taint [ 61.715872][ T203] Kernel panic - not syncing: panic_on_warn set ... [ 61.722466][ T203] CPU: 1 PID: 203 Comm: kworker/u4:4 Tainted: G B 5.8.0-rc2-syzkaller #0 [ 61.732171][ T203] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.742235][ T203] Workqueue: netns cleanup_net [ 61.747112][ T203] Call Trace: [ 61.750411][ T203] dump_stack+0x18f/0x20d [ 61.754846][ T203] ? afs_wake_up_async_call+0x360/0x4a0 [ 61.760491][ T203] ? afs_put_call+0x440/0x440 [ 61.765866][ T203] panic+0x2e3/0x75c [ 61.769765][ T203] ? __warn_printk+0xf3/0xf3 [ 61.774364][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.779908][ T203] ? trace_hardirqs_on+0x55/0x220 [ 61.785021][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.790581][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.797076][ T203] ? afs_put_call+0x440/0x440 [ 61.801750][ T203] end_report+0x4d/0x53 [ 61.805903][ T203] kasan_report.cold+0xd/0x37 [ 61.810581][ T203] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.816116][ T203] afs_wake_up_async_call+0x430/0x4a0 [ 61.821479][ T203] ? afs_close_socket+0x320/0x320 [ 61.826508][ T203] rxrpc_notify_socket+0x1db/0x5d0 [ 61.831788][ T203] ? afs_put_call+0x440/0x440 [ 61.836462][ T203] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.842868][ T203] rxrpc_call_completed+0xd0/0xf0 [ 61.847884][ T203] rxrpc_discard_prealloc+0x777/0xab0 [ 61.853338][ T203] ? lock_sock_nested+0x94/0x110 [ 61.858791][ T203] rxrpc_listen+0x11c/0x330 [ 61.863290][ T203] afs_close_socket+0x95/0x320 [ 61.868053][ T203] ? afs_purge_servers+0x181/0x330 [ 61.873161][ T203] ? afs_rx_discard_new_call+0x50/0x50 [ 61.878617][ T203] ? init_wait_var_entry+0x200/0x200 [ 61.884086][ T203] afs_net_exit+0x1c4/0x310 [ 61.888584][ T203] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.894384][ T203] ops_exit_list+0xb0/0x160 [ 61.898883][ T203] cleanup_net+0x4ea/0xa00 [ 61.903485][ T203] ? __schedule+0x887/0x1eb0 [ 61.908223][ T203] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.913599][ T203] ? check_preemption_disabled+0x38/0x220 [ 61.919325][ T203] process_one_work+0x94c/0x1670 [ 61.924790][ T203] ? lock_release+0x8d0/0x8d0 [ 61.929481][ T203] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.934965][ T203] ? rwlock_bug.part.0+0x90/0x90 [ 61.939899][ T203] worker_thread+0x64c/0x1120 [ 61.944574][ T203] ? __kthread_parkme+0x13f/0x1e0 [ 61.949591][ T203] ? process_one_work+0x1670/0x1670 [ 61.954790][ T203] kthread+0x3b5/0x4a0 [ 61.958854][ T203] ? __kthread_bind_mask+0xc0/0xc0 [ 61.964051][ T203] ? __kthread_bind_mask+0xc0/0xc0 [ 61.969250][ T203] ret_from_fork+0x1f/0x30 [ 61.975226][ T203] Kernel Offset: disabled [ 61.979566][ T203] Rebooting in 86400 seconds..