[ 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 '10.128.0.66' (ECDSA) to the list of known hosts. 2020/06/19 00:40:15 fuzzer started 2020/06/19 00:40:15 connecting to host at 10.128.0.26:43367 2020/06/19 00:40:15 checking machine... 2020/06/19 00:40:15 checking revisions... 2020/06/19 00:40:15 testing simple program... syzkaller login: [ 61.179727][ T6790] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 00:40:16 building call list... [ 61.494041][ T6749] tipc: TX() has been purged, node left! [ 62.036393][ T6749] ================================================================== [ 62.045372][ T6749] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.054067][ T6749] Write of size 1 at addr ffff88809ea3a9e4 by task kworker/u4:6/6749 [ 62.062314][ T6749] [ 62.064680][ T6749] CPU: 1 PID: 6749 Comm: kworker/u4:6 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.073092][ T6749] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.083253][ T6749] Workqueue: netns cleanup_net [ 62.088373][ T6749] Call Trace: [ 62.091673][ T6749] dump_stack+0x18f/0x20d [ 62.096043][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.101910][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.107862][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.112573][ T6749] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.119987][ T6749] ? vprintk_func+0x97/0x1a6 [ 62.124598][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.130151][ T6749] kasan_report.cold+0x1f/0x37 [ 62.134927][ T6749] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.140580][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.146146][ T6749] afs_wake_up_async_call+0x6aa/0x770 [ 62.151868][ T6749] ? afs_close_socket+0x320/0x320 [ 62.156929][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.161807][ T6749] rxrpc_notify_socket+0x1db/0x5d0 [ 62.167038][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.171921][ T6749] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.178351][ T6749] rxrpc_call_completed+0xca/0xf0 [ 62.183399][ T6749] rxrpc_discard_prealloc+0x781/0xab0 [ 62.188781][ T6749] ? lock_sock_nested+0x94/0x110 [ 62.193814][ T6749] rxrpc_listen+0x147/0x360 [ 62.198329][ T6749] afs_close_socket+0x95/0x320 [ 62.203112][ T6749] ? afs_purge_servers+0x16d/0x300 [ 62.208237][ T6749] ? afs_rx_discard_new_call+0x50/0x50 [ 62.213807][ T6749] ? init_wait_var_entry+0x200/0x200 [ 62.219102][ T6749] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.224832][ T6749] ? check_preemption_disabled+0x38/0x220 [ 62.230759][ T6749] afs_net_exit+0x1bc/0x310 [ 62.235272][ T6749] ? afs_net_init+0xe30/0xe30 [ 62.239958][ T6749] ops_exit_list.isra.0+0xa8/0x150 [ 62.245275][ T6749] cleanup_net+0x511/0xa50 [ 62.249706][ T6749] ? unregister_pernet_device+0x70/0x70 [ 62.255310][ T6749] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.261300][ T6749] process_one_work+0x965/0x1690 [ 62.266253][ T6749] ? lock_release+0x800/0x800 [ 62.270953][ T6749] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.276332][ T6749] ? rwlock_bug.part.0+0x90/0x90 [ 62.281285][ T6749] worker_thread+0x96/0xe10 [ 62.285805][ T6749] ? process_one_work+0x1690/0x1690 [ 62.291013][ T6749] kthread+0x3b5/0x4a0 [ 62.295084][ T6749] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.300821][ T6749] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.306544][ T6749] ret_from_fork+0x1f/0x30 [ 62.310992][ T6749] [ 62.313317][ T6749] Allocated by task 6790: [ 62.317653][ T6749] save_stack+0x1b/0x40 [ 62.321834][ T6749] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.327467][ T6749] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.332839][ T6749] afs_alloc_call+0x55/0x630 [ 62.338229][ T6749] afs_charge_preallocation+0xe9/0x2d0 [ 62.343696][ T6749] afs_open_socket+0x292/0x360 [ 62.348456][ T6749] afs_net_init+0xa6c/0xe30 [ 62.352977][ T6749] ops_init+0xaf/0x420 [ 62.357130][ T6749] setup_net+0x2de/0x860 [ 62.361377][ T6749] copy_net_ns+0x293/0x590 [ 62.365804][ T6749] create_new_namespaces+0x3fb/0xb30 [ 62.371178][ T6749] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.376813][ T6749] ksys_unshare+0x43d/0x8e0 [ 62.381348][ T6749] __x64_sys_unshare+0x2d/0x40 [ 62.386255][ T6749] do_syscall_64+0x60/0xe0 [ 62.390880][ T6749] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.396776][ T6749] [ 62.399103][ T6749] Freed by task 6749: [ 62.403124][ T6749] save_stack+0x1b/0x40 [ 62.407277][ T6749] __kasan_slab_free+0xf7/0x140 [ 62.412132][ T6749] kfree+0x109/0x2b0 [ 62.416021][ T6749] afs_put_call+0x585/0xa40 [ 62.420523][ T6749] rxrpc_discard_prealloc+0x764/0xab0 [ 62.425898][ T6749] rxrpc_listen+0x147/0x360 [ 62.430397][ T6749] afs_close_socket+0x95/0x320 [ 62.435243][ T6749] afs_net_exit+0x1bc/0x310 [ 62.439749][ T6749] ops_exit_list.isra.0+0xa8/0x150 [ 62.444858][ T6749] cleanup_net+0x511/0xa50 [ 62.449376][ T6749] process_one_work+0x965/0x1690 [ 62.454412][ T6749] worker_thread+0x96/0xe10 [ 62.459105][ T6749] kthread+0x3b5/0x4a0 [ 62.463199][ T6749] ret_from_fork+0x1f/0x30 [ 62.467617][ T6749] [ 62.470035][ T6749] The buggy address belongs to the object at ffff88809ea3a800 [ 62.470035][ T6749] which belongs to the cache kmalloc-1k of size 1024 [ 62.485145][ T6749] The buggy address is located 484 bytes inside of [ 62.485145][ T6749] 1024-byte region [ffff88809ea3a800, ffff88809ea3ac00) [ 62.498608][ T6749] The buggy address belongs to the page: [ 62.504272][ T6749] page:ffffea00027a8e80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.513605][ T6749] flags: 0xfffe0000000200(slab) [ 62.518479][ T6749] raw: 00fffe0000000200 ffffea00027efdc8 ffffea00025742c8 ffff8880aa000c40 [ 62.527084][ T6749] raw: 0000000000000000 ffff88809ea3a000 0000000100000002 0000000000000000 [ 62.536040][ T6749] page dumped because: kasan: bad access detected [ 62.542535][ T6749] [ 62.544895][ T6749] Memory state around the buggy address: [ 62.551846][ T6749] ffff88809ea3a880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.560082][ T6749] ffff88809ea3a900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.568513][ T6749] >ffff88809ea3a980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.576922][ T6749] ^ [ 62.584113][ T6749] ffff88809ea3aa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.592271][ T6749] ffff88809ea3aa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.600322][ T6749] ================================================================== [ 62.608417][ T6749] Disabling lock debugging due to kernel taint [ 62.614625][ T6749] Kernel panic - not syncing: panic_on_warn set ... [ 62.621213][ T6749] CPU: 1 PID: 6749 Comm: kworker/u4:6 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.631098][ T6749] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.641249][ T6749] Workqueue: netns cleanup_net [ 62.646097][ T6749] Call Trace: [ 62.649403][ T6749] dump_stack+0x18f/0x20d [ 62.653757][ T6749] ? afs_wake_up_async_call+0x680/0x770 [ 62.659310][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.664025][ T6749] panic+0x2e3/0x75c [ 62.667915][ T6749] ? __warn_printk+0xf3/0xf3 [ 62.672514][ T6749] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.678698][ T6749] ? trace_hardirqs_on+0x55/0x220 [ 62.683733][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.689281][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.694816][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.699497][ T6749] end_report+0x4d/0x53 [ 62.703648][ T6749] kasan_report.cold+0xd/0x37 [ 62.708327][ T6749] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.713988][ T6749] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.721197][ T6749] afs_wake_up_async_call+0x6aa/0x770 [ 62.726747][ T6749] ? afs_close_socket+0x320/0x320 [ 62.731780][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.736449][ T6749] rxrpc_notify_socket+0x1db/0x5d0 [ 62.741560][ T6749] ? afs_put_call+0xa40/0xa40 [ 62.746229][ T6749] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.752644][ T6749] rxrpc_call_completed+0xca/0xf0 [ 62.757840][ T6749] rxrpc_discard_prealloc+0x781/0xab0 [ 62.763208][ T6749] ? lock_sock_nested+0x94/0x110 [ 62.768254][ T6749] rxrpc_listen+0x147/0x360 [ 62.772758][ T6749] afs_close_socket+0x95/0x320 [ 62.777519][ T6749] ? afs_purge_servers+0x16d/0x300 [ 62.782626][ T6749] ? afs_rx_discard_new_call+0x50/0x50 [ 62.788077][ T6749] ? init_wait_var_entry+0x200/0x200 [ 62.793358][ T6749] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.798986][ T6749] ? check_preemption_disabled+0x38/0x220 [ 62.804906][ T6749] afs_net_exit+0x1bc/0x310 [ 62.809403][ T6749] ? afs_net_init+0xe30/0xe30 [ 62.814069][ T6749] ops_exit_list.isra.0+0xa8/0x150 [ 62.819174][ T6749] cleanup_net+0x511/0xa50 [ 62.823616][ T6749] ? unregister_pernet_device+0x70/0x70 [ 62.829157][ T6749] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.835133][ T6749] process_one_work+0x965/0x1690 [ 62.840079][ T6749] ? lock_release+0x800/0x800 [ 62.844751][ T6749] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.850202][ T6749] ? rwlock_bug.part.0+0x90/0x90 [ 62.855140][ T6749] worker_thread+0x96/0xe10 [ 62.859661][ T6749] ? process_one_work+0x1690/0x1690 [ 62.864860][ T6749] kthread+0x3b5/0x4a0 [ 62.868926][ T6749] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.874636][ T6749] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.880534][ T6749] ret_from_fork+0x1f/0x30 [ 62.886423][ T6749] Kernel Offset: disabled [ 62.890741][ T6749] Rebooting in 86400 seconds..