Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.51' (ECDSA) to the list of known hosts. 2020/06/16 02:51:56 fuzzer started 2020/06/16 02:51:56 connecting to host at 10.128.0.26:43829 2020/06/16 02:51:56 checking machine... 2020/06/16 02:51:56 checking revisions... 2020/06/16 02:51:56 testing simple program... 2020/06/16 02:51:57 building call list... syzkaller login: [ 62.879544][ T6832] IPVS: ftp: loaded support on port[0] = 21 [ 63.232196][ T43] tipc: TX() has been purged, node left! [ 63.733943][ T43] ================================================================== [ 63.742217][ T43] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 63.750138][ T43] Write of size 1 at addr ffff88809fec51e4 by task kworker/u4:3/43 [ 63.758031][ T43] [ 63.760362][ T43] CPU: 0 PID: 43 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-next-20200615-syzkaller #0 [ 63.769803][ T43] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.779872][ T43] Workqueue: netns cleanup_net [ 63.784638][ T43] Call Trace: [ 63.787938][ T43] dump_stack+0x18f/0x20d [ 63.792275][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.797816][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.803364][ T43] ? afs_put_call+0xa40/0xa40 [ 63.808045][ T43] print_address_description.constprop.0.cold+0xd3/0x413 [ 63.815076][ T43] ? vprintk_func+0x97/0x1a6 [ 63.819670][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.825216][ T43] kasan_report.cold+0x1f/0x37 [ 63.829985][ T43] ? rcu_read_lock_held_common+0x71/0xa0 [ 63.835613][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.841160][ T43] afs_wake_up_async_call+0x6aa/0x770 [ 63.846535][ T43] ? afs_close_socket+0x320/0x320 [ 63.851559][ T43] ? afs_put_call+0xa40/0xa40 [ 63.856231][ T43] rxrpc_notify_socket+0x1db/0x5d0 [ 63.861577][ T43] ? afs_put_call+0xa40/0xa40 [ 63.866270][ T43] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.872711][ T43] rxrpc_call_completed+0xca/0xf0 [ 63.877769][ T43] rxrpc_discard_prealloc+0x781/0xab0 [ 63.883164][ T43] ? lock_sock_nested+0x94/0x110 [ 63.888115][ T43] rxrpc_listen+0x147/0x360 [ 63.892636][ T43] afs_close_socket+0x95/0x320 [ 63.897405][ T43] ? afs_purge_servers+0x16d/0x300 [ 63.902517][ T43] ? afs_rx_discard_new_call+0x50/0x50 [ 63.907980][ T43] ? init_wait_var_entry+0x200/0x200 [ 63.913267][ T43] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.919036][ T43] ? check_preemption_disabled+0x38/0x220 [ 63.924911][ T43] afs_net_exit+0x1bc/0x310 [ 63.929426][ T43] ? afs_net_init+0xe30/0xe30 [ 63.934110][ T43] ops_exit_list.isra.0+0xa8/0x150 [ 63.939228][ T43] cleanup_net+0x511/0xa50 [ 63.943669][ T43] ? unregister_pernet_device+0x70/0x70 [ 63.949226][ T43] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.955228][ T43] process_one_work+0x965/0x1690 [ 63.960182][ T43] ? lock_release+0x800/0x800 [ 63.964859][ T43] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.970236][ T43] ? rwlock_bug.part.0+0x90/0x90 [ 63.975192][ T43] worker_thread+0x96/0xe10 [ 63.979710][ T43] ? process_one_work+0x1690/0x1690 [ 63.984911][ T43] kthread+0x3b5/0x4a0 [ 63.988978][ T43] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.994693][ T43] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.000416][ T43] ret_from_fork+0x1f/0x30 [ 64.004845][ T43] [ 64.007172][ T43] Allocated by task 6832: [ 64.011501][ T43] save_stack+0x1b/0x40 [ 64.015653][ T43] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 64.021280][ T43] kmem_cache_alloc_trace+0x153/0x7d0 [ 64.026650][ T43] afs_alloc_call+0x55/0x630 [ 64.031236][ T43] afs_charge_preallocation+0xe9/0x2d0 [ 64.036688][ T43] afs_open_socket+0x292/0x360 [ 64.041478][ T43] afs_net_init+0xa6c/0xe30 [ 64.045974][ T43] ops_init+0xaf/0x420 [ 64.050059][ T43] setup_net+0x2de/0x860 [ 64.054301][ T43] copy_net_ns+0x293/0x590 [ 64.058719][ T43] create_new_namespaces+0x3fb/0xb30 [ 64.064009][ T43] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 64.069637][ T43] ksys_unshare+0x43d/0x8e0 [ 64.074225][ T43] __x64_sys_unshare+0x2d/0x40 [ 64.078986][ T43] do_syscall_64+0x60/0xe0 [ 64.083400][ T43] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 64.089279][ T43] [ 64.091610][ T43] Freed by task 43: [ 64.095431][ T43] save_stack+0x1b/0x40 [ 64.099596][ T43] __kasan_slab_free+0xf7/0x140 [ 64.104448][ T43] kfree+0x109/0x2b0 [ 64.108342][ T43] afs_put_call+0x585/0xa40 [ 64.112844][ T43] rxrpc_discard_prealloc+0x764/0xab0 [ 64.118209][ T43] rxrpc_listen+0x147/0x360 [ 64.122718][ T43] afs_close_socket+0x95/0x320 [ 64.128016][ T43] afs_net_exit+0x1bc/0x310 [ 64.132518][ T43] ops_exit_list.isra.0+0xa8/0x150 [ 64.137622][ T43] cleanup_net+0x511/0xa50 [ 64.142039][ T43] process_one_work+0x965/0x1690 [ 64.146972][ T43] worker_thread+0x96/0xe10 [ 64.151483][ T43] kthread+0x3b5/0x4a0 [ 64.155548][ T43] ret_from_fork+0x1f/0x30 [ 64.159961][ T43] [ 64.162296][ T43] The buggy address belongs to the object at ffff88809fec5000 [ 64.162296][ T43] which belongs to the cache kmalloc-1k of size 1024 [ 64.176357][ T43] The buggy address is located 484 bytes inside of [ 64.176357][ T43] 1024-byte region [ffff88809fec5000, ffff88809fec5400) [ 64.189832][ T43] The buggy address belongs to the page: [ 64.195505][ T43] page:ffffea00027fb140 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 64.204635][ T43] flags: 0xfffe0000000200(slab) [ 64.209497][ T43] raw: 00fffe0000000200 ffffea00028df088 ffffea00028b6e08 ffff8880aa000c40 [ 64.218101][ T43] raw: 0000000000000000 ffff88809fec5000 0000000100000002 0000000000000000 [ 64.226720][ T43] page dumped because: kasan: bad access detected [ 64.233145][ T43] [ 64.235498][ T43] Memory state around the buggy address: [ 64.241309][ T43] ffff88809fec5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.249404][ T43] ffff88809fec5100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.257481][ T43] >ffff88809fec5180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.265582][ T43] ^ [ 64.272804][ T43] ffff88809fec5200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.280899][ T43] ffff88809fec5280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 64.289110][ T43] ================================================================== [ 64.297177][ T43] Disabling lock debugging due to kernel taint [ 64.303368][ T43] Kernel panic - not syncing: panic_on_warn set ... [ 64.309959][ T43] CPU: 0 PID: 43 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-next-20200615-syzkaller #0 [ 64.320838][ T43] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.330911][ T43] Workqueue: netns cleanup_net [ 64.335669][ T43] Call Trace: [ 64.338958][ T43] dump_stack+0x18f/0x20d [ 64.343293][ T43] ? afs_wake_up_async_call+0x660/0x770 [ 64.348832][ T43] ? afs_put_call+0xa40/0xa40 [ 64.353505][ T43] panic+0x2e3/0x75c [ 64.357399][ T43] ? __warn_printk+0xf3/0xf3 [ 64.361990][ T43] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 64.368144][ T43] ? trace_hardirqs_on+0x55/0x220 [ 64.373172][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.378799][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.384336][ T43] ? afs_put_call+0xa40/0xa40 [ 64.389005][ T43] end_report+0x4d/0x53 [ 64.393156][ T43] kasan_report.cold+0xd/0x37 [ 64.397828][ T43] ? rcu_read_lock_held_common+0x71/0xa0 [ 64.403450][ T43] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.408995][ T43] afs_wake_up_async_call+0x6aa/0x770 [ 64.414357][ T43] ? afs_close_socket+0x320/0x320 [ 64.419633][ T43] ? afs_put_call+0xa40/0xa40 [ 64.424301][ T43] rxrpc_notify_socket+0x1db/0x5d0 [ 64.429411][ T43] ? afs_put_call+0xa40/0xa40 [ 64.434080][ T43] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 64.440489][ T43] rxrpc_call_completed+0xca/0xf0 [ 64.445515][ T43] rxrpc_discard_prealloc+0x781/0xab0 [ 64.450886][ T43] ? lock_sock_nested+0x94/0x110 [ 64.455818][ T43] rxrpc_listen+0x147/0x360 [ 64.460315][ T43] afs_close_socket+0x95/0x320 [ 64.465197][ T43] ? afs_purge_servers+0x16d/0x300 [ 64.470321][ T43] ? afs_rx_discard_new_call+0x50/0x50 [ 64.475788][ T43] ? init_wait_var_entry+0x200/0x200 [ 64.481071][ T43] ? rcu_read_lock_held_common+0xa0/0xa0 [ 64.486705][ T43] ? check_preemption_disabled+0x38/0x220 [ 64.492419][ T43] afs_net_exit+0x1bc/0x310 [ 64.496916][ T43] ? afs_net_init+0xe30/0xe30 [ 64.501593][ T43] ops_exit_list.isra.0+0xa8/0x150 [ 64.506699][ T43] cleanup_net+0x511/0xa50 [ 64.511112][ T43] ? unregister_pernet_device+0x70/0x70 [ 64.516657][ T43] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 64.522641][ T43] process_one_work+0x965/0x1690 [ 64.527590][ T43] ? lock_release+0x800/0x800 [ 64.532278][ T43] ? pwq_dec_nr_in_flight+0x310/0x310 [ 64.537652][ T43] ? rwlock_bug.part.0+0x90/0x90 [ 64.542594][ T43] worker_thread+0x96/0xe10 [ 64.547101][ T43] ? process_one_work+0x1690/0x1690 [ 64.552294][ T43] kthread+0x3b5/0x4a0 [ 64.556385][ T43] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.562096][ T43] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.568678][ T43] ret_from_fork+0x1f/0x30 [ 64.574432][ T43] Kernel Offset: disabled [ 64.578998][ T43] Rebooting in 86400 seconds..