[ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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 '10.128.15.194' (ECDSA) to the list of known hosts. 2020/06/19 18:03:12 fuzzer started 2020/06/19 18:03:13 connecting to host at 10.128.0.26:38435 2020/06/19 18:03:13 checking machine... 2020/06/19 18:03:13 checking revisions... 2020/06/19 18:03:13 testing simple program... syzkaller login: [ 61.305045][ T6821] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 18:03:13 building call list... [ 61.668937][ T94] tipc: TX() has been purged, node left! [ 62.190966][ T94] ================================================================== [ 62.199479][ T94] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.207749][ T94] Write of size 1 at addr ffff88809394b1e4 by task kworker/u4:3/94 [ 62.215765][ T94] [ 62.218120][ T94] CPU: 1 PID: 94 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.226375][ T94] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.236557][ T94] Workqueue: netns cleanup_net [ 62.241417][ T94] Call Trace: [ 62.244729][ T94] dump_stack+0x18f/0x20d [ 62.249082][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.254784][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.261410][ T94] ? afs_put_call+0xa40/0xa40 [ 62.266117][ T94] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.273170][ T94] ? vprintk_func+0x97/0x1a6 [ 62.277784][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.283349][ T94] kasan_report.cold+0x1f/0x37 [ 62.288148][ T94] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.293831][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.299405][ T94] afs_wake_up_async_call+0x6aa/0x770 [ 62.306793][ T94] ? afs_close_socket+0x320/0x320 [ 62.311834][ T94] ? afs_put_call+0xa40/0xa40 [ 62.316525][ T94] rxrpc_notify_socket+0x1db/0x5d0 [ 62.321671][ T94] ? afs_put_call+0xa40/0xa40 [ 62.326521][ T94] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.333045][ T94] rxrpc_call_completed+0xca/0xf0 [ 62.338181][ T94] rxrpc_discard_prealloc+0x781/0xab0 [ 62.343663][ T94] ? lock_sock_nested+0x94/0x110 [ 62.348712][ T94] rxrpc_listen+0x147/0x360 [ 62.353243][ T94] afs_close_socket+0x95/0x320 [ 62.358058][ T94] ? afs_purge_servers+0x16d/0x300 [ 62.363252][ T94] ? afs_rx_discard_new_call+0x50/0x50 [ 62.368734][ T94] ? init_wait_var_entry+0x200/0x200 [ 62.374036][ T94] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.379686][ T94] ? check_preemption_disabled+0x38/0x220 [ 62.385426][ T94] afs_net_exit+0x1bc/0x310 [ 62.389942][ T94] ? afs_net_init+0xe30/0xe30 [ 62.394632][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 62.399759][ T94] cleanup_net+0x511/0xa50 [ 62.404280][ T94] ? unregister_pernet_device+0x70/0x70 [ 62.410118][ T94] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.416186][ T94] process_one_work+0x965/0x1690 [ 62.421152][ T94] ? lock_release+0x800/0x800 [ 62.425914][ T94] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.431396][ T94] ? rwlock_bug.part.0+0x90/0x90 [ 62.436386][ T94] worker_thread+0x96/0xe10 [ 62.441004][ T94] ? process_one_work+0x1690/0x1690 [ 62.446222][ T94] kthread+0x3b5/0x4a0 [ 62.450307][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.456044][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.461849][ T94] ret_from_fork+0x1f/0x30 [ 62.466502][ T94] [ 62.468989][ T94] Allocated by task 6821: [ 62.473328][ T94] save_stack+0x1b/0x40 [ 62.477494][ T94] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.483319][ T94] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.488853][ T94] afs_alloc_call+0x55/0x630 [ 62.493452][ T94] afs_charge_preallocation+0xe9/0x2d0 [ 62.499010][ T94] afs_open_socket+0x292/0x360 [ 62.503815][ T94] afs_net_init+0xa6c/0xe30 [ 62.508328][ T94] ops_init+0xaf/0x420 [ 62.512404][ T94] setup_net+0x2de/0x860 [ 62.516741][ T94] copy_net_ns+0x293/0x590 [ 62.521174][ T94] create_new_namespaces+0x3fb/0xb30 [ 62.526471][ T94] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.532120][ T94] ksys_unshare+0x43d/0x8e0 [ 62.536637][ T94] __x64_sys_unshare+0x2d/0x40 [ 62.541410][ T94] do_syscall_64+0x60/0xe0 [ 62.546016][ T94] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.552086][ T94] [ 62.554427][ T94] Freed by task 94: [ 62.558255][ T94] save_stack+0x1b/0x40 [ 62.562436][ T94] __kasan_slab_free+0xf7/0x140 [ 62.567307][ T94] kfree+0x109/0x2b0 [ 62.571219][ T94] afs_put_call+0x585/0xa40 [ 62.575737][ T94] rxrpc_discard_prealloc+0x764/0xab0 [ 62.581118][ T94] rxrpc_listen+0x147/0x360 [ 62.585634][ T94] afs_close_socket+0x95/0x320 [ 62.590474][ T94] afs_net_exit+0x1bc/0x310 [ 62.594987][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 62.600109][ T94] cleanup_net+0x511/0xa50 [ 62.604542][ T94] process_one_work+0x965/0x1690 [ 62.609617][ T94] worker_thread+0x96/0xe10 [ 62.614134][ T94] kthread+0x3b5/0x4a0 [ 62.618213][ T94] ret_from_fork+0x1f/0x30 [ 62.622718][ T94] [ 62.625059][ T94] The buggy address belongs to the object at ffff88809394b000 [ 62.625059][ T94] which belongs to the cache kmalloc-1k of size 1024 [ 62.639302][ T94] The buggy address is located 484 bytes inside of [ 62.639302][ T94] 1024-byte region [ffff88809394b000, ffff88809394b400) [ 62.652921][ T94] The buggy address belongs to the page: [ 62.658667][ T94] page:ffffea00024e52c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.667782][ T94] flags: 0xfffe0000000200(slab) [ 62.672652][ T94] raw: 00fffe0000000200 ffffea0002888388 ffffea0002580148 ffff8880aa000c40 [ 62.681517][ T94] raw: 0000000000000000 ffff88809394b000 0000000100000002 0000000000000000 [ 62.690109][ T94] page dumped because: kasan: bad access detected [ 62.696947][ T94] [ 62.699282][ T94] Memory state around the buggy address: [ 62.704923][ T94] ffff88809394b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.712998][ T94] ffff88809394b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.721216][ T94] >ffff88809394b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.729386][ T94] ^ [ 62.736681][ T94] ffff88809394b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.744892][ T94] ffff88809394b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.753053][ T94] ================================================================== [ 62.761121][ T94] Disabling lock debugging due to kernel taint [ 62.767749][ T94] Kernel panic - not syncing: panic_on_warn set ... [ 62.774747][ T94] CPU: 1 PID: 94 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.784556][ T94] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.794887][ T94] Workqueue: netns cleanup_net [ 62.799656][ T94] Call Trace: [ 62.803051][ T94] dump_stack+0x18f/0x20d [ 62.807401][ T94] ? afs_wake_up_async_call+0x670/0x770 [ 62.813116][ T94] ? afs_put_call+0xa40/0xa40 [ 62.817897][ T94] panic+0x2e3/0x75c [ 62.821906][ T94] ? __warn_printk+0xf3/0xf3 [ 62.826600][ T94] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.832773][ T94] ? trace_hardirqs_on+0x55/0x220 [ 62.838172][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.843819][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.849761][ T94] ? afs_put_call+0xa40/0xa40 [ 62.854443][ T94] end_report+0x4d/0x53 [ 62.858726][ T94] kasan_report.cold+0xd/0x37 [ 62.863608][ T94] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.869255][ T94] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.874994][ T94] afs_wake_up_async_call+0x6aa/0x770 [ 62.880474][ T94] ? afs_close_socket+0x320/0x320 [ 62.885639][ T94] ? afs_put_call+0xa40/0xa40 [ 62.890331][ T94] rxrpc_notify_socket+0x1db/0x5d0 [ 62.895461][ T94] ? afs_put_call+0xa40/0xa40 [ 62.900141][ T94] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.907030][ T94] rxrpc_call_completed+0xca/0xf0 [ 62.915544][ T94] rxrpc_discard_prealloc+0x781/0xab0 [ 62.920932][ T94] ? lock_sock_nested+0x94/0x110 [ 62.926019][ T94] rxrpc_listen+0x147/0x360 [ 62.930534][ T94] afs_close_socket+0x95/0x320 [ 62.935310][ T94] ? afs_purge_servers+0x16d/0x300 [ 62.940431][ T94] ? afs_rx_discard_new_call+0x50/0x50 [ 62.946061][ T94] ? init_wait_var_entry+0x200/0x200 [ 62.951908][ T94] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.957554][ T94] ? check_preemption_disabled+0x38/0x220 [ 62.963289][ T94] afs_net_exit+0x1bc/0x310 [ 62.967984][ T94] ? afs_net_init+0xe30/0xe30 [ 62.972834][ T94] ops_exit_list.isra.0+0xa8/0x150 [ 62.977957][ T94] cleanup_net+0x511/0xa50 [ 62.982379][ T94] ? unregister_pernet_device+0x70/0x70 [ 62.987940][ T94] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.993928][ T94] process_one_work+0x965/0x1690 [ 62.999018][ T94] ? lock_release+0x800/0x800 [ 63.003699][ T94] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.009078][ T94] ? rwlock_bug.part.0+0x90/0x90 [ 63.014106][ T94] worker_thread+0x96/0xe10 [ 63.018973][ T94] ? process_one_work+0x1690/0x1690 [ 63.024405][ T94] kthread+0x3b5/0x4a0 [ 63.028632][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.034529][ T94] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.040269][ T94] ret_from_fork+0x1f/0x30 [ 63.046325][ T94] Kernel Offset: disabled [ 63.050718][ T94] Rebooting in 86400 seconds..