[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ 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 '10.128.10.53' (ECDSA) to the list of known hosts. 2020/06/19 08:21:05 fuzzer started 2020/06/19 08:21:05 connecting to host at 10.128.0.26:37961 2020/06/19 08:21:05 checking machine... 2020/06/19 08:21:05 checking revisions... 2020/06/19 08:21:05 testing simple program... syzkaller login: [ 60.571711][ T6818] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 08:21:06 building call list... [ 60.919205][ T21] tipc: TX() has been purged, node left! [ 61.421584][ T21] ================================================================== [ 61.429864][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.437751][ T21] Write of size 1 at addr ffff88809f34d1e4 by task kworker/u4:1/21 [ 61.445717][ T21] [ 61.448063][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.456325][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.466382][ T21] Workqueue: netns cleanup_net [ 61.471167][ T21] Call Trace: [ 61.474470][ T21] dump_stack+0x18f/0x20d [ 61.478812][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.484814][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.490359][ T21] ? afs_put_call+0xa40/0xa40 [ 61.495040][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.502507][ T21] ? vprintk_func+0x97/0x1a6 [ 61.507100][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.512643][ T21] kasan_report.cold+0x1f/0x37 [ 61.517434][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.523239][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.528964][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 61.534334][ T21] ? afs_close_socket+0x320/0x320 [ 61.539358][ T21] ? afs_put_call+0xa40/0xa40 [ 61.544033][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 61.549155][ T21] ? afs_put_call+0xa40/0xa40 [ 61.554017][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.560532][ T21] rxrpc_call_completed+0xca/0xf0 [ 61.565569][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 61.571039][ T21] ? lock_sock_nested+0x94/0x110 [ 61.575984][ T21] rxrpc_listen+0x147/0x360 [ 61.580492][ T21] afs_close_socket+0x95/0x320 [ 61.585256][ T21] ? afs_purge_servers+0x16d/0x300 [ 61.590394][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 61.595917][ T21] ? init_wait_var_entry+0x200/0x200 [ 61.601217][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.607070][ T21] ? check_preemption_disabled+0x38/0x220 [ 61.612807][ T21] afs_net_exit+0x1bc/0x310 [ 61.617332][ T21] ? afs_net_init+0xe30/0xe30 [ 61.622008][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.627124][ T21] cleanup_net+0x511/0xa50 [ 61.631541][ T21] ? unregister_pernet_device+0x70/0x70 [ 61.637100][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.643278][ T21] process_one_work+0x965/0x1690 [ 61.648228][ T21] ? lock_release+0x800/0x800 [ 61.652906][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.658359][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 61.663309][ T21] worker_thread+0x96/0xe10 [ 61.667830][ T21] ? process_one_work+0x1690/0x1690 [ 61.673032][ T21] kthread+0x3b5/0x4a0 [ 61.677100][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.682816][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.688555][ T21] ret_from_fork+0x1f/0x30 [ 61.693005][ T21] [ 61.695416][ T21] Allocated by task 6818: [ 61.699744][ T21] save_stack+0x1b/0x40 [ 61.703999][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.709733][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.715110][ T21] afs_alloc_call+0x55/0x630 [ 61.719699][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 61.725157][ T21] afs_open_socket+0x292/0x360 [ 61.729937][ T21] afs_net_init+0xa6c/0xe30 [ 61.734436][ T21] ops_init+0xaf/0x420 [ 61.738499][ T21] setup_net+0x2de/0x860 [ 61.742756][ T21] copy_net_ns+0x293/0x590 [ 61.747172][ T21] create_new_namespaces+0x3fb/0xb30 [ 61.752587][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.758684][ T21] ksys_unshare+0x43d/0x8e0 [ 61.763222][ T21] __x64_sys_unshare+0x2d/0x40 [ 61.768028][ T21] do_syscall_64+0x60/0xe0 [ 61.772568][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.778468][ T21] [ 61.780813][ T21] Freed by task 21: [ 61.784715][ T21] save_stack+0x1b/0x40 [ 61.788879][ T21] __kasan_slab_free+0xf7/0x140 [ 61.793746][ T21] kfree+0x109/0x2b0 [ 61.797726][ T21] afs_put_call+0x585/0xa40 [ 61.802229][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 61.807686][ T21] rxrpc_listen+0x147/0x360 [ 61.812199][ T21] afs_close_socket+0x95/0x320 [ 61.816956][ T21] afs_net_exit+0x1bc/0x310 [ 61.821629][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.826733][ T21] cleanup_net+0x511/0xa50 [ 61.831179][ T21] process_one_work+0x965/0x1690 [ 61.836135][ T21] worker_thread+0x96/0xe10 [ 61.840637][ T21] kthread+0x3b5/0x4a0 [ 61.844704][ T21] ret_from_fork+0x1f/0x30 [ 61.849114][ T21] [ 61.851443][ T21] The buggy address belongs to the object at ffff88809f34d000 [ 61.851443][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 61.865589][ T21] The buggy address is located 484 bytes inside of [ 61.865589][ T21] 1024-byte region [ffff88809f34d000, ffff88809f34d400) [ 61.879028][ T21] The buggy address belongs to the page: [ 61.884663][ T21] page:ffffea00027cd340 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.893861][ T21] flags: 0xfffe0000000200(slab) [ 61.898750][ T21] raw: 00fffe0000000200 ffffea00029efc08 ffffea000280a808 ffff8880aa000c40 [ 61.907606][ T21] raw: 0000000000000000 ffff88809f34d000 0000000100000002 0000000000000000 [ 61.916186][ T21] page dumped because: kasan: bad access detected [ 61.924154][ T21] [ 61.926477][ T21] Memory state around the buggy address: [ 61.932304][ T21] ffff88809f34d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.940450][ T21] ffff88809f34d100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.948615][ T21] >ffff88809f34d180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.957632][ T21] ^ [ 61.964837][ T21] ffff88809f34d200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.973524][ T21] ffff88809f34d280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.981587][ T21] ================================================================== [ 61.989736][ T21] Disabling lock debugging due to kernel taint [ 61.995960][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 62.002561][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.012274][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.022539][ T21] Workqueue: netns cleanup_net [ 62.027327][ T21] Call Trace: [ 62.030623][ T21] dump_stack+0x18f/0x20d [ 62.034961][ T21] ? afs_wake_up_async_call+0x670/0x770 [ 62.040509][ T21] ? afs_put_call+0xa40/0xa40 [ 62.045186][ T21] panic+0x2e3/0x75c [ 62.049964][ T21] ? __warn_printk+0xf3/0xf3 [ 62.054671][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.060818][ T21] ? trace_hardirqs_on+0x55/0x220 [ 62.065845][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.071385][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.076918][ T21] ? afs_put_call+0xa40/0xa40 [ 62.081588][ T21] end_report+0x4d/0x53 [ 62.085809][ T21] kasan_report.cold+0xd/0x37 [ 62.090659][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.096429][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.102201][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.107572][ T21] ? afs_close_socket+0x320/0x320 [ 62.112708][ T21] ? afs_put_call+0xa40/0xa40 [ 62.117375][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.122477][ T21] ? afs_put_call+0xa40/0xa40 [ 62.127171][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.133623][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.138635][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 62.144038][ T21] ? lock_sock_nested+0x94/0x110 [ 62.148973][ T21] rxrpc_listen+0x147/0x360 [ 62.153550][ T21] afs_close_socket+0x95/0x320 [ 62.158298][ T21] ? afs_purge_servers+0x16d/0x300 [ 62.163425][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.168876][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.174158][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.179788][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.185516][ T21] afs_net_exit+0x1bc/0x310 [ 62.190009][ T21] ? afs_net_init+0xe30/0xe30 [ 62.194832][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.199940][ T21] cleanup_net+0x511/0xa50 [ 62.205016][ T21] ? unregister_pernet_device+0x70/0x70 [ 62.211305][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.217756][ T21] process_one_work+0x965/0x1690 [ 62.222715][ T21] ? lock_release+0x800/0x800 [ 62.227383][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.232837][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.237796][ T21] worker_thread+0x96/0xe10 [ 62.242302][ T21] ? process_one_work+0x1690/0x1690 [ 62.247535][ T21] kthread+0x3b5/0x4a0 [ 62.251611][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.257436][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.263325][ T21] ret_from_fork+0x1f/0x30 [ 62.269248][ T21] Kernel Offset: disabled [ 62.273584][ T21] Rebooting in 86400 seconds..