[ OK ] Started OpenBSD Secure Shell server. [ OK ] Started getty on tty2-tty6 if dbus and logind are not available. [ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ 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. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.225' (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 10.128.0.26:34033 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: [ 59.854804][ T6861] IPVS: ftp: loaded support on port[0] = 21 2020/06/17 04:40:32 building call list... [ 60.238110][ T150] tipc: TX() has been purged, node left! [ 60.760372][ T150] ================================================================== [ 60.768626][ T150] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 60.776513][ T150] Write of size 1 at addr ffff88809389f9e4 by task kworker/u4:4/150 [ 60.784496][ T150] [ 60.786862][ T150] CPU: 1 PID: 150 Comm: kworker/u4:4 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.795176][ T150] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.805230][ T150] Workqueue: netns cleanup_net [ 60.809985][ T150] Call Trace: [ 60.813277][ T150] dump_stack+0x18f/0x20d [ 60.817605][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.823177][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.828739][ T150] ? afs_put_call+0xa40/0xa40 [ 60.833415][ T150] print_address_description.constprop.0.cold+0xd3/0x413 [ 60.840441][ T150] ? vprintk_func+0x97/0x1a6 [ 60.845033][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.850575][ T150] kasan_report.cold+0x1f/0x37 [ 60.855341][ T150] ? rcu_read_lock_held_common+0x51/0xa0 [ 60.860967][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.866517][ T150] afs_wake_up_async_call+0x6aa/0x770 [ 60.871884][ T150] ? afs_close_socket+0x320/0x320 [ 60.876907][ T150] ? afs_put_call+0xa40/0xa40 [ 60.881587][ T150] rxrpc_notify_socket+0x1db/0x5d0 [ 60.886711][ T150] ? afs_put_call+0xa40/0xa40 [ 60.891415][ T150] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.897830][ T150] rxrpc_call_completed+0xca/0xf0 [ 60.902855][ T150] rxrpc_discard_prealloc+0x781/0xab0 [ 60.908230][ T150] ? lock_sock_nested+0x94/0x110 [ 60.913170][ T150] rxrpc_listen+0x147/0x360 [ 60.917672][ T150] afs_close_socket+0x95/0x320 [ 60.922430][ T150] ? afs_purge_servers+0x16d/0x300 [ 60.927539][ T150] ? afs_rx_discard_new_call+0x50/0x50 [ 60.932997][ T150] ? init_wait_var_entry+0x200/0x200 [ 60.938286][ T150] ? rcu_read_lock_held_common+0xa0/0xa0 [ 60.943915][ T150] ? check_preemption_disabled+0x38/0x220 [ 60.949639][ T150] afs_net_exit+0x1bc/0x310 [ 60.954154][ T150] ? afs_net_init+0xe30/0xe30 [ 60.958830][ T150] ops_exit_list.isra.0+0xa8/0x150 [ 60.963941][ T150] cleanup_net+0x511/0xa50 [ 60.968362][ T150] ? unregister_pernet_device+0x70/0x70 [ 60.973907][ T150] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.979894][ T150] process_one_work+0x965/0x1690 [ 60.984841][ T150] ? lock_release+0x800/0x800 [ 60.989530][ T150] ? pwq_dec_nr_in_flight+0x310/0x310 [ 60.994917][ T150] ? rwlock_bug.part.0+0x90/0x90 [ 60.999862][ T150] worker_thread+0x96/0xe10 [ 61.004393][ T150] ? process_one_work+0x1690/0x1690 [ 61.009599][ T150] kthread+0x3b5/0x4a0 [ 61.013670][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.019408][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.025129][ T150] ret_from_fork+0x1f/0x30 [ 61.029552][ T150] [ 61.031878][ T150] Allocated by task 6861: [ 61.036205][ T150] save_stack+0x1b/0x40 [ 61.040355][ T150] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.045983][ T150] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.051347][ T150] afs_alloc_call+0x55/0x630 [ 61.055931][ T150] afs_charge_preallocation+0xe9/0x2d0 [ 61.061385][ T150] afs_open_socket+0x292/0x360 [ 61.066140][ T150] afs_net_init+0xa6c/0xe30 [ 61.070635][ T150] ops_init+0xaf/0x420 [ 61.074698][ T150] setup_net+0x2de/0x860 [ 61.078945][ T150] copy_net_ns+0x293/0x590 [ 61.083372][ T150] create_new_namespaces+0x3fb/0xb30 [ 61.088671][ T150] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.094373][ T150] ksys_unshare+0x43d/0x8e0 [ 61.098889][ T150] __x64_sys_unshare+0x2d/0x40 [ 61.103649][ T150] do_syscall_64+0x60/0xe0 [ 61.108060][ T150] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.114195][ T150] [ 61.116517][ T150] Freed by task 150: [ 61.120410][ T150] save_stack+0x1b/0x40 [ 61.124561][ T150] __kasan_slab_free+0xf7/0x140 [ 61.129419][ T150] kfree+0x109/0x2b0 [ 61.133425][ T150] afs_put_call+0x585/0xa40 [ 61.137938][ T150] rxrpc_discard_prealloc+0x764/0xab0 [ 61.143318][ T150] rxrpc_listen+0x147/0x360 [ 61.147814][ T150] afs_close_socket+0x95/0x320 [ 61.152564][ T150] afs_net_exit+0x1bc/0x310 [ 61.157050][ T150] ops_exit_list.isra.0+0xa8/0x150 [ 61.162249][ T150] cleanup_net+0x511/0xa50 [ 61.166656][ T150] process_one_work+0x965/0x1690 [ 61.171590][ T150] worker_thread+0x96/0xe10 [ 61.176091][ T150] kthread+0x3b5/0x4a0 [ 61.180156][ T150] ret_from_fork+0x1f/0x30 [ 61.184557][ T150] [ 61.186883][ T150] The buggy address belongs to the object at ffff88809389f800 [ 61.186883][ T150] which belongs to the cache kmalloc-1k of size 1024 [ 61.200930][ T150] The buggy address is located 484 bytes inside of [ 61.200930][ T150] 1024-byte region [ffff88809389f800, ffff88809389fc00) [ 61.214275][ T150] The buggy address belongs to the page: [ 61.219905][ T150] page:ffffea00024e27c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.229089][ T150] flags: 0xfffe0000000200(slab) [ 61.233939][ T150] raw: 00fffe0000000200 ffffea00027a2988 ffffea00024bd8c8 ffff8880aa000c40 [ 61.242518][ T150] raw: 0000000000000000 ffff88809389f000 0000000100000002 0000000000000000 [ 61.251088][ T150] page dumped because: kasan: bad access detected [ 61.257485][ T150] [ 61.259805][ T150] Memory state around the buggy address: [ 61.265431][ T150] ffff88809389f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.273487][ T150] ffff88809389f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.281549][ T150] >ffff88809389f980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.289601][ T150] ^ [ 61.296793][ T150] ffff88809389fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.304853][ T150] ffff88809389fa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.312997][ T150] ================================================================== [ 61.321052][ T150] Disabling lock debugging due to kernel taint [ 61.327237][ T150] Kernel panic - not syncing: panic_on_warn set ... [ 61.333820][ T150] CPU: 1 PID: 150 Comm: kworker/u4:4 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.343518][ T150] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.353567][ T150] Workqueue: netns cleanup_net [ 61.358318][ T150] Call Trace: [ 61.361604][ T150] dump_stack+0x18f/0x20d [ 61.365926][ T150] ? afs_wake_up_async_call+0x670/0x770 [ 61.371460][ T150] ? afs_put_call+0xa40/0xa40 [ 61.376125][ T150] panic+0x2e3/0x75c [ 61.380013][ T150] ? __warn_printk+0xf3/0xf3 [ 61.384595][ T150] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 61.390743][ T150] ? trace_hardirqs_on+0x55/0x220 [ 61.395774][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.401311][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.406843][ T150] ? afs_put_call+0xa40/0xa40 [ 61.411596][ T150] end_report+0x4d/0x53 [ 61.415744][ T150] kasan_report.cold+0xd/0x37 [ 61.420420][ T150] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.426076][ T150] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.431632][ T150] afs_wake_up_async_call+0x6aa/0x770 [ 61.436999][ T150] ? afs_close_socket+0x320/0x320 [ 61.442017][ T150] ? afs_put_call+0xa40/0xa40 [ 61.446686][ T150] rxrpc_notify_socket+0x1db/0x5d0 [ 61.451789][ T150] ? afs_put_call+0xa40/0xa40 [ 61.456456][ T150] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.462862][ T150] rxrpc_call_completed+0xca/0xf0 [ 61.467898][ T150] rxrpc_discard_prealloc+0x781/0xab0 [ 61.473263][ T150] ? lock_sock_nested+0x94/0x110 [ 61.478287][ T150] rxrpc_listen+0x147/0x360 [ 61.482784][ T150] afs_close_socket+0x95/0x320 [ 61.487536][ T150] ? afs_purge_servers+0x16d/0x300 [ 61.492636][ T150] ? afs_rx_discard_new_call+0x50/0x50 [ 61.498086][ T150] ? init_wait_var_entry+0x200/0x200 [ 61.503367][ T150] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.509000][ T150] ? check_preemption_disabled+0x38/0x220 [ 61.514711][ T150] afs_net_exit+0x1bc/0x310 [ 61.519205][ T150] ? afs_net_init+0xe30/0xe30 [ 61.523868][ T150] ops_exit_list.isra.0+0xa8/0x150 [ 61.528973][ T150] cleanup_net+0x511/0xa50 [ 61.533380][ T150] ? unregister_pernet_device+0x70/0x70 [ 61.538919][ T150] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.544894][ T150] process_one_work+0x965/0x1690 [ 61.549827][ T150] ? lock_release+0x800/0x800 [ 61.554493][ T150] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.559855][ T150] ? rwlock_bug.part.0+0x90/0x90 [ 61.564795][ T150] worker_thread+0x96/0xe10 [ 61.569293][ T150] ? process_one_work+0x1690/0x1690 [ 61.574480][ T150] kthread+0x3b5/0x4a0 [ 61.578542][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.584258][ T150] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.589982][ T150] ret_from_fork+0x1f/0x30 [ 61.595985][ T150] Kernel Offset: disabled [ 61.600297][ T150] Rebooting in 86400 seconds..