[ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... Starting Load/Save RF Kill Switch Status... [ OK ] Started Update UTMP about System Runlevel Changes. [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.72' (ECDSA) to the list of known hosts. 2020/06/17 04:40:32 fuzzer started 2020/06/17 04:40:32 connecting to host at 10.128.0.26:43773 2020/06/17 04:40:32 checking machine... 2020/06/17 04:40:32 checking revisions... 2020/06/17 04:40:32 testing simple program... syzkaller login: [ 61.009965][ T6791] IPVS: ftp: loaded support on port[0] = 21 2020/06/17 04:40:32 building call list... [ 61.321571][ T7] tipc: TX() has been purged, node left! [ 61.803671][ T7] ================================================================== [ 61.811989][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.819963][ T7] Write of size 1 at addr ffff8880953f19e4 by task kworker/u4:0/7 [ 61.827753][ T7] [ 61.830122][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.838265][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.848332][ T7] Workqueue: netns cleanup_net [ 61.853087][ T7] Call Trace: [ 61.856378][ T7] dump_stack+0x18f/0x20d [ 61.860716][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.866260][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.871800][ T7] ? afs_put_call+0xa40/0xa40 [ 61.876476][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.883600][ T7] ? vprintk_func+0x97/0x1a6 [ 61.888193][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.893740][ T7] kasan_report.cold+0x1f/0x37 [ 61.898526][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.904171][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.909720][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 61.915434][ T7] ? afs_close_socket+0x320/0x320 [ 61.920459][ T7] ? afs_put_call+0xa40/0xa40 [ 61.925134][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 61.930247][ T7] ? afs_put_call+0xa40/0xa40 [ 61.934923][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.941343][ T7] rxrpc_call_completed+0xca/0xf0 [ 61.946371][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 61.951743][ T7] ? lock_sock_nested+0x94/0x110 [ 61.956685][ T7] rxrpc_listen+0x147/0x360 [ 61.961190][ T7] afs_close_socket+0x95/0x320 [ 61.965950][ T7] ? afs_purge_servers+0x16d/0x300 [ 61.971063][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 61.976532][ T7] ? init_wait_var_entry+0x200/0x200 [ 61.981845][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.987476][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.993199][ T7] afs_net_exit+0x1bc/0x310 [ 61.997697][ T7] ? afs_net_init+0xe30/0xe30 [ 62.002387][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.007498][ T7] cleanup_net+0x511/0xa50 [ 62.011919][ T7] ? unregister_pernet_device+0x70/0x70 [ 62.017471][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.023461][ T7] process_one_work+0x965/0x1690 [ 62.028406][ T7] ? lock_release+0x800/0x800 [ 62.033085][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.038461][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 62.043409][ T7] worker_thread+0x96/0xe10 [ 62.047926][ T7] ? process_one_work+0x1690/0x1690 [ 62.053126][ T7] kthread+0x3b5/0x4a0 [ 62.057191][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.062998][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.068719][ T7] ret_from_fork+0x1f/0x30 [ 62.073162][ T7] [ 62.075493][ T7] Allocated by task 6791: [ 62.079819][ T7] save_stack+0x1b/0x40 [ 62.083974][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.089601][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.094966][ T7] afs_alloc_call+0x55/0x630 [ 62.099552][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 62.105012][ T7] afs_open_socket+0x292/0x360 [ 62.109770][ T7] afs_net_init+0xa6c/0xe30 [ 62.114271][ T7] ops_init+0xaf/0x420 [ 62.118334][ T7] setup_net+0x2de/0x860 [ 62.122577][ T7] copy_net_ns+0x293/0x590 [ 62.126991][ T7] create_new_namespaces+0x3fb/0xb30 [ 62.132281][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.137910][ T7] ksys_unshare+0x43d/0x8e0 [ 62.142413][ T7] __x64_sys_unshare+0x2d/0x40 [ 62.147173][ T7] do_syscall_64+0x60/0xe0 [ 62.151603][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.157481][ T7] [ 62.159800][ T7] Freed by task 7: [ 62.163515][ T7] save_stack+0x1b/0x40 [ 62.167669][ T7] __kasan_slab_free+0xf7/0x140 [ 62.172516][ T7] kfree+0x109/0x2b0 [ 62.176424][ T7] afs_put_call+0x585/0xa40 [ 62.180925][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 62.186292][ T7] rxrpc_listen+0x147/0x360 [ 62.190809][ T7] afs_close_socket+0x95/0x320 [ 62.195569][ T7] afs_net_exit+0x1bc/0x310 [ 62.200066][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.205192][ T7] cleanup_net+0x511/0xa50 [ 62.209631][ T7] process_one_work+0x965/0x1690 [ 62.214584][ T7] worker_thread+0x96/0xe10 [ 62.219088][ T7] kthread+0x3b5/0x4a0 [ 62.223153][ T7] ret_from_fork+0x1f/0x30 [ 62.227574][ T7] [ 62.229899][ T7] The buggy address belongs to the object at ffff8880953f1800 [ 62.229899][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 62.243974][ T7] The buggy address is located 484 bytes inside of [ 62.243974][ T7] 1024-byte region [ffff8880953f1800, ffff8880953f1c00) [ 62.257326][ T7] The buggy address belongs to the page: [ 62.262957][ T7] page:ffffea000254fc40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.272081][ T7] flags: 0xfffe0000000200(slab) [ 62.276933][ T7] raw: 00fffe0000000200 ffffea0002553808 ffffea0002568a48 ffff8880aa000c40 [ 62.285522][ T7] raw: 0000000000000000 ffff8880953f1000 0000000100000002 0000000000000000 [ 62.294205][ T7] page dumped because: kasan: bad access detected [ 62.300625][ T7] [ 62.302964][ T7] Memory state around the buggy address: [ 62.308616][ T7] ffff8880953f1880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.316675][ T7] ffff8880953f1900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.324744][ T7] >ffff8880953f1980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.332799][ T7] ^ [ 62.340030][ T7] ffff8880953f1a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.348096][ T7] ffff8880953f1a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.356147][ T7] ================================================================== [ 62.364197][ T7] Disabling lock debugging due to kernel taint [ 62.370515][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 62.377106][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.386652][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.396714][ T7] Workqueue: netns cleanup_net [ 62.401468][ T7] Call Trace: [ 62.404758][ T7] dump_stack+0x18f/0x20d [ 62.409090][ T7] ? afs_wake_up_async_call+0x670/0x770 [ 62.414633][ T7] ? afs_put_call+0xa40/0xa40 [ 62.419355][ T7] panic+0x2e3/0x75c [ 62.423424][ T7] ? __warn_printk+0xf3/0xf3 [ 62.428020][ T7] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.434187][ T7] ? trace_hardirqs_on+0x55/0x220 [ 62.439213][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.444757][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.450293][ T7] ? afs_put_call+0xa40/0xa40 [ 62.454965][ T7] end_report+0x4d/0x53 [ 62.459117][ T7] kasan_report.cold+0xd/0x37 [ 62.463794][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.469418][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.474956][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 62.480341][ T7] ? afs_close_socket+0x320/0x320 [ 62.485482][ T7] ? afs_put_call+0xa40/0xa40 [ 62.490173][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 62.495286][ T7] ? afs_put_call+0xa40/0xa40 [ 62.499974][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.506554][ T7] rxrpc_call_completed+0xca/0xf0 [ 62.511580][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 62.516946][ T7] ? lock_sock_nested+0x94/0x110 [ 62.521882][ T7] rxrpc_listen+0x147/0x360 [ 62.526465][ T7] afs_close_socket+0x95/0x320 [ 62.531399][ T7] ? afs_purge_servers+0x16d/0x300 [ 62.536510][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 62.542048][ T7] ? init_wait_var_entry+0x200/0x200 [ 62.547327][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.552951][ T7] ? check_preemption_disabled+0x38/0x220 [ 62.558660][ T7] afs_net_exit+0x1bc/0x310 [ 62.563152][ T7] ? afs_net_init+0xe30/0xe30 [ 62.567831][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.573020][ T7] cleanup_net+0x511/0xa50 [ 62.577431][ T7] ? unregister_pernet_device+0x70/0x70 [ 62.582972][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.588947][ T7] process_one_work+0x965/0x1690 [ 62.593877][ T7] ? lock_release+0x800/0x800 [ 62.598544][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.604002][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 62.608933][ T7] worker_thread+0x96/0xe10 [ 62.613437][ T7] ? process_one_work+0x1690/0x1690 [ 62.618629][ T7] kthread+0x3b5/0x4a0 [ 62.622688][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.628411][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.634145][ T7] ret_from_fork+0x1f/0x30 [ 62.640158][ T7] Kernel Offset: disabled [ 62.644564][ T7] Rebooting in 86400 seconds..