[ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.15.199' (ECDSA) to the list of known hosts. 2020/06/19 04:08:28 fuzzer started 2020/06/19 04:08:29 connecting to host at 10.128.0.26:35093 2020/06/19 04:08:29 checking machine... 2020/06/19 04:08:29 checking revisions... 2020/06/19 04:08:29 testing simple program... syzkaller login: [ 63.942612][ T6825] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 04:08:29 building call list... [ 64.321882][ T94] tipc: TX() has been purged, node left! [ 64.824262][ T94] ================================================================== [ 64.832504][ T94] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 64.840405][ T94] Write of size 1 at addr ffff88809571d9e4 by task kworker/u4:3/94 [ 64.848284][ T94] [ 64.850616][ T94] CPU: 1 PID: 94 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 64.859287][ T94] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.869342][ T94] Workqueue: netns cleanup_net [ 64.874095][ T94] Call Trace: [ 64.877392][ T94] dump_stack+0x18f/0x20d [ 64.881724][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.887265][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.892807][ T94] ? afs_put_call+0xa40/0xa40 [ 64.897482][ T94] print_address_description.constprop.0.cold+0xd3/0x413 [ 64.904765][ T94] ? vprintk_func+0x97/0x1a6 [ 64.909357][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.914922][ T94] kasan_report.cold+0x1f/0x37 [ 64.919687][ T94] ? rcu_read_lock_held_common+0x51/0xa0 [ 64.925313][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.930871][ T94] afs_wake_up_async_call+0x6aa/0x770 [ 64.936244][ T94] ? afs_close_socket+0x320/0x320 [ 64.941263][ T94] ? afs_put_call+0xa40/0xa40 [ 64.945937][ T94] rxrpc_notify_socket+0x1db/0x5d0 [ 64.951051][ T94] ? afs_put_call+0xa40/0xa40 [ 64.955735][ T94] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 64.962149][ T94] rxrpc_call_completed+0xca/0xf0 [ 64.967177][ T94] rxrpc_discard_prealloc+0x781/0xab0 [ 64.972549][ T94] ? lock_sock_nested+0x94/0x110 [ 64.977487][ T94] rxrpc_listen+0x147/0x360 [ 64.981989][ T94] afs_close_socket+0x95/0x320 [ 64.986752][ T94] ? afs_purge_servers+0x16d/0x300 [ 64.991863][ T94] ? afs_rx_discard_new_call+0x50/0x50 [ 64.997321][ T94] ? init_wait_var_entry+0x200/0x200 [ 65.002607][ T94] ? rcu_read_lock_held_common+0xa0/0xa0 [ 65.008235][ T94] ? check_preemption_disabled+0x38/0x220 [ 65.013955][ T94] afs_net_exit+0x1bc/0x310 [ 65.018455][ T94] ? afs_net_init+0xe30/0xe30 [ 65.023128][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 65.028257][ T94] cleanup_net+0x511/0xa50 [ 65.032677][ T94] ? unregister_pernet_device+0x70/0x70 [ 65.038225][ T94] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 65.044208][ T94] process_one_work+0x965/0x1690 [ 65.049151][ T94] ? lock_release+0x800/0x800 [ 65.053829][ T94] ? pwq_dec_nr_in_flight+0x310/0x310 [ 65.059202][ T94] ? rwlock_bug.part.0+0x90/0x90 [ 65.064148][ T94] worker_thread+0x96/0xe10 [ 65.068662][ T94] ? process_one_work+0x1690/0x1690 [ 65.073858][ T94] kthread+0x3b5/0x4a0 [ 65.077925][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.083636][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.089355][ T94] ret_from_fork+0x1f/0x30 [ 65.093895][ T94] [ 65.096218][ T94] Allocated by task 6825: [ 65.100543][ T94] save_stack+0x1b/0x40 [ 65.104695][ T94] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 65.110413][ T94] kmem_cache_alloc_trace+0x153/0x7d0 [ 65.115777][ T94] afs_alloc_call+0x55/0x630 [ 65.120359][ T94] afs_charge_preallocation+0xe9/0x2d0 [ 65.125834][ T94] afs_open_socket+0x292/0x360 [ 65.130591][ T94] afs_net_init+0xa6c/0xe30 [ 65.136999][ T94] ops_init+0xaf/0x420 [ 65.141059][ T94] setup_net+0x2de/0x860 [ 65.145292][ T94] copy_net_ns+0x293/0x590 [ 65.149704][ T94] create_new_namespaces+0x3fb/0xb30 [ 65.154998][ T94] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 65.160625][ T94] ksys_unshare+0x43d/0x8e0 [ 65.165125][ T94] __x64_sys_unshare+0x2d/0x40 [ 65.169884][ T94] do_syscall_64+0x60/0xe0 [ 65.174296][ T94] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 65.180171][ T94] [ 65.182490][ T94] Freed by task 94: [ 65.186293][ T94] save_stack+0x1b/0x40 [ 65.190538][ T94] __kasan_slab_free+0xf7/0x140 [ 65.195393][ T94] kfree+0x109/0x2b0 [ 65.199295][ T94] afs_put_call+0x585/0xa40 [ 65.203806][ T94] rxrpc_discard_prealloc+0x764/0xab0 [ 65.209194][ T94] rxrpc_listen+0x147/0x360 [ 65.213703][ T94] afs_close_socket+0x95/0x320 [ 65.218459][ T94] afs_net_exit+0x1bc/0x310 [ 65.222954][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 65.228055][ T94] cleanup_net+0x511/0xa50 [ 65.232484][ T94] process_one_work+0x965/0x1690 [ 65.237415][ T94] worker_thread+0x96/0xe10 [ 65.241909][ T94] kthread+0x3b5/0x4a0 [ 65.245974][ T94] ret_from_fork+0x1f/0x30 [ 65.250373][ T94] [ 65.252704][ T94] The buggy address belongs to the object at ffff88809571d800 [ 65.252704][ T94] which belongs to the cache kmalloc-1k of size 1024 [ 65.266749][ T94] The buggy address is located 484 bytes inside of [ 65.266749][ T94] 1024-byte region [ffff88809571d800, ffff88809571dc00) [ 65.280266][ T94] The buggy address belongs to the page: [ 65.285892][ T94] page:ffffea000255c740 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 65.294990][ T94] flags: 0xfffe0000000200(slab) [ 65.299928][ T94] raw: 00fffe0000000200 ffffea00027bfa88 ffffea00028be908 ffff8880aa000c40 [ 65.308508][ T94] raw: 0000000000000000 ffff88809571d000 0000000100000002 0000000000000000 [ 65.317078][ T94] page dumped because: kasan: bad access detected [ 65.323736][ T94] [ 65.326055][ T94] Memory state around the buggy address: [ 65.331699][ T94] ffff88809571d880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.339760][ T94] ffff88809571d900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.347812][ T94] >ffff88809571d980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.356320][ T94] ^ [ 65.363544][ T94] ffff88809571da00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.371689][ T94] ffff88809571da80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.379756][ T94] ================================================================== [ 65.387806][ T94] Disabling lock debugging due to kernel taint [ 65.394020][ T94] Kernel panic - not syncing: panic_on_warn set ... [ 65.400610][ T94] CPU: 1 PID: 94 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 65.410236][ T94] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.420321][ T94] Workqueue: netns cleanup_net [ 65.425077][ T94] Call Trace: [ 65.428403][ T94] dump_stack+0x18f/0x20d [ 65.432736][ T94] ? afs_wake_up_async_call+0x670/0x770 [ 65.438287][ T94] ? afs_put_call+0xa40/0xa40 [ 65.442967][ T94] panic+0x2e3/0x75c [ 65.446864][ T94] ? __warn_printk+0xf3/0xf3 [ 65.451454][ T94] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 65.457614][ T94] ? trace_hardirqs_on+0x55/0x220 [ 65.462627][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.468181][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.473720][ T94] ? afs_put_call+0xa40/0xa40 [ 65.478394][ T94] end_report+0x4d/0x53 [ 65.482550][ T94] kasan_report.cold+0xd/0x37 [ 65.487231][ T94] ? rcu_read_lock_held_common+0x51/0xa0 [ 65.492861][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.498400][ T94] afs_wake_up_async_call+0x6aa/0x770 [ 65.503762][ T94] ? afs_close_socket+0x320/0x320 [ 65.508787][ T94] ? afs_put_call+0xa40/0xa40 [ 65.513453][ T94] rxrpc_notify_socket+0x1db/0x5d0 [ 65.518543][ T94] ? afs_put_call+0xa40/0xa40 [ 65.523206][ T94] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 65.529607][ T94] rxrpc_call_completed+0xca/0xf0 [ 65.534617][ T94] rxrpc_discard_prealloc+0x781/0xab0 [ 65.540010][ T94] ? lock_sock_nested+0x94/0x110 [ 65.544939][ T94] rxrpc_listen+0x147/0x360 [ 65.549425][ T94] afs_close_socket+0x95/0x320 [ 65.554178][ T94] ? afs_purge_servers+0x16d/0x300 [ 65.559271][ T94] ? afs_rx_discard_new_call+0x50/0x50 [ 65.564721][ T94] ? init_wait_var_entry+0x200/0x200 [ 65.570074][ T94] ? rcu_read_lock_held_common+0xa0/0xa0 [ 65.575697][ T94] ? check_preemption_disabled+0x38/0x220 [ 65.581408][ T94] afs_net_exit+0x1bc/0x310 [ 65.585895][ T94] ? afs_net_init+0xe30/0xe30 [ 65.590551][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 65.595637][ T94] cleanup_net+0x511/0xa50 [ 65.600033][ T94] ? unregister_pernet_device+0x70/0x70 [ 65.605570][ T94] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 65.611545][ T94] process_one_work+0x965/0x1690 [ 65.616908][ T94] ? lock_release+0x800/0x800 [ 65.621565][ T94] ? pwq_dec_nr_in_flight+0x310/0x310 [ 65.626931][ T94] ? rwlock_bug.part.0+0x90/0x90 [ 65.631867][ T94] worker_thread+0x96/0xe10 [ 65.636359][ T94] ? process_one_work+0x1690/0x1690 [ 65.641537][ T94] kthread+0x3b5/0x4a0 [ 65.646110][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.651802][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.657516][ T94] ret_from_fork+0x1f/0x30 [ 65.663431][ T94] Kernel Offset: disabled [ 65.667757][ T94] Rebooting in 86400 seconds..