[ 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 '10.128.15.200' (ECDSA) to the list of known hosts. 2020/06/25 14:58:18 fuzzer started 2020/06/25 14:58:19 connecting to host at 10.128.0.26:34535 2020/06/25 14:58:19 checking machine... 2020/06/25 14:58:19 checking revisions... 2020/06/25 14:58:19 testing simple program... syzkaller login: [ 65.935215][ T6866] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 14:58:19 building call list... [ 66.259760][ T21] tipc: TX() has been purged, node left! [ 66.792019][ T21] ================================================================== [ 66.804084][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 66.812953][ T21] Write of size 1 at addr ffff8880a8e2b1e4 by task kworker/u4:1/21 [ 66.823197][ T21] [ 66.825627][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 66.838948][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 66.850154][ T21] Workqueue: netns cleanup_net [ 66.855226][ T21] Call Trace: [ 66.858774][ T21] dump_stack+0x18f/0x20d [ 66.863420][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 66.870286][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 66.877508][ T21] ? afs_put_call+0x440/0x440 [ 66.883799][ T21] print_address_description.constprop.0.cold+0xae/0x436 [ 66.894062][ T21] ? vprintk_func+0x97/0x1a6 [ 66.899283][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 66.905765][ T21] kasan_report.cold+0x1f/0x37 [ 66.911234][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 66.917672][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 66.923695][ T21] ? afs_close_socket+0x320/0x320 [ 66.929101][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 66.934258][ T21] ? afs_put_call+0x440/0x440 [ 66.939370][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 66.945890][ T21] rxrpc_call_completed+0xd0/0xf0 [ 66.950930][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 66.956313][ T21] ? lock_sock_nested+0x94/0x110 [ 66.966378][ T21] rxrpc_listen+0x11c/0x330 [ 66.972257][ T21] afs_close_socket+0x95/0x320 [ 66.978199][ T21] ? afs_purge_servers+0x16d/0x300 [ 66.985019][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 66.992398][ T21] ? init_wait_var_entry+0x200/0x200 [ 66.998345][ T21] ? check_preemption_disabled+0x38/0x220 [ 67.006029][ T21] afs_net_exit+0x1bc/0x310 [ 67.012403][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 67.019451][ T21] ops_exit_list+0xb0/0x160 [ 67.024237][ T21] cleanup_net+0x4ea/0xa00 [ 67.029106][ T21] ? __schedule+0x887/0x1eb0 [ 67.034436][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 67.041465][ T21] ? check_preemption_disabled+0x38/0x220 [ 67.047203][ T21] process_one_work+0x94c/0x1670 [ 67.052251][ T21] ? lock_release+0x8d0/0x8d0 [ 67.057610][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 67.064133][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 67.071126][ T21] worker_thread+0x64c/0x1120 [ 67.075975][ T21] ? process_one_work+0x1670/0x1670 [ 67.081382][ T21] kthread+0x3b5/0x4a0 [ 67.085581][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 67.090733][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 67.095954][ T21] ret_from_fork+0x1f/0x30 [ 67.100758][ T21] [ 67.103624][ T21] Allocated by task 6866: [ 67.112622][ T21] save_stack+0x1b/0x40 [ 67.117765][ T21] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 67.123969][ T21] kmem_cache_alloc_trace+0x14f/0x2d0 [ 67.130215][ T21] afs_alloc_call+0x4f/0x360 [ 67.134819][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 67.140637][ T21] afs_open_socket+0x294/0x360 [ 67.145674][ T21] afs_net_init+0xa6c/0xe30 [ 67.150178][ T21] ops_init+0xaf/0x470 [ 67.154375][ T21] setup_net+0x2d8/0x850 [ 67.159361][ T21] copy_net_ns+0x2cf/0x5e0 [ 67.164372][ T21] create_new_namespaces+0x3f6/0xb10 [ 67.171588][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 67.177924][ T21] ksys_unshare+0x36c/0x9a0 [ 67.182529][ T21] __x64_sys_unshare+0x2d/0x40 [ 67.188825][ T21] do_syscall_64+0x60/0xe0 [ 67.196016][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 67.203015][ T21] [ 67.205614][ T21] Freed by task 21: [ 67.209613][ T21] save_stack+0x1b/0x40 [ 67.213897][ T21] __kasan_slab_free+0xf5/0x140 [ 67.219580][ T21] kfree+0x103/0x2c0 [ 67.224214][ T21] afs_put_call+0x345/0x440 [ 67.229132][ T21] rxrpc_discard_prealloc+0x75a/0xab0 [ 67.235465][ T21] rxrpc_listen+0x11c/0x330 [ 67.239972][ T21] afs_close_socket+0x95/0x320 [ 67.244943][ T21] afs_net_exit+0x1bc/0x310 [ 67.249987][ T21] ops_exit_list+0xb0/0x160 [ 67.255199][ T21] cleanup_net+0x4ea/0xa00 [ 67.260414][ T21] process_one_work+0x94c/0x1670 [ 67.265661][ T21] worker_thread+0x64c/0x1120 [ 67.270719][ T21] kthread+0x3b5/0x4a0 [ 67.274910][ T21] ret_from_fork+0x1f/0x30 [ 67.279739][ T21] [ 67.282243][ T21] The buggy address belongs to the object at ffff8880a8e2b000 [ 67.282243][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 67.297707][ T21] The buggy address is located 484 bytes inside of [ 67.297707][ T21] 1024-byte region [ffff8880a8e2b000, ffff8880a8e2b400) [ 67.312285][ T21] The buggy address belongs to the page: [ 67.318107][ T21] page:ffffea0002a38ac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 67.334026][ T21] flags: 0xfffe0000000200(slab) [ 67.340235][ T21] raw: 00fffe0000000200 ffffea00029de208 ffffea00029af3c8 ffff8880aa000c40 [ 67.349361][ T21] raw: 0000000000000000 ffff8880a8e2b000 0000000100000002 0000000000000000 [ 67.358194][ T21] page dumped because: kasan: bad access detected [ 67.364949][ T21] [ 67.367317][ T21] Memory state around the buggy address: [ 67.372976][ T21] ffff8880a8e2b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 67.382155][ T21] ffff8880a8e2b100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 67.391086][ T21] >ffff8880a8e2b180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 67.399678][ T21] ^ [ 67.407743][ T21] ffff8880a8e2b200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 67.422067][ T21] ffff8880a8e2b280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 67.430476][ T21] ================================================================== [ 67.438741][ T21] Disabling lock debugging due to kernel taint [ 67.445698][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 67.452408][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 67.462387][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 67.473121][ T21] Workqueue: netns cleanup_net [ 67.478984][ T21] Call Trace: [ 67.482330][ T21] dump_stack+0x18f/0x20d [ 67.487024][ T21] ? afs_wake_up_async_call+0x370/0x4a0 [ 67.495659][ T21] ? afs_put_call+0x440/0x440 [ 67.502207][ T21] panic+0x2e3/0x75c [ 67.506725][ T21] ? __warn_printk+0xf3/0xf3 [ 67.512248][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 67.518344][ T21] ? trace_hardirqs_on+0x55/0x220 [ 67.525500][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 67.532082][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 67.538407][ T21] ? afs_put_call+0x440/0x440 [ 67.543209][ T21] end_report+0x4d/0x53 [ 67.547656][ T21] kasan_report.cold+0xd/0x37 [ 67.552710][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 67.560353][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 67.567983][ T21] ? afs_close_socket+0x320/0x320 [ 67.573146][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 67.579000][ T21] ? afs_put_call+0x440/0x440 [ 67.584914][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 67.593131][ T21] rxrpc_call_completed+0xd0/0xf0 [ 67.599618][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 67.606452][ T21] ? lock_sock_nested+0x94/0x110 [ 67.612809][ T21] rxrpc_listen+0x11c/0x330 [ 67.618940][ T21] afs_close_socket+0x95/0x320 [ 67.627007][ T21] ? afs_purge_servers+0x16d/0x300 [ 67.634499][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 67.641444][ T21] ? init_wait_var_entry+0x200/0x200 [ 67.647930][ T21] ? check_preemption_disabled+0x38/0x220 [ 67.654887][ T21] afs_net_exit+0x1bc/0x310 [ 67.660771][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 67.667305][ T21] ops_exit_list+0xb0/0x160 [ 67.672540][ T21] cleanup_net+0x4ea/0xa00 [ 67.677109][ T21] ? __schedule+0x887/0x1eb0 [ 67.681913][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 67.687850][ T21] ? check_preemption_disabled+0x38/0x220 [ 67.693704][ T21] process_one_work+0x94c/0x1670 [ 67.698886][ T21] ? lock_release+0x8d0/0x8d0 [ 67.703917][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 67.714584][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 67.720758][ T21] worker_thread+0x64c/0x1120 [ 67.725461][ T21] ? process_one_work+0x1670/0x1670 [ 67.731267][ T21] kthread+0x3b5/0x4a0 [ 67.737377][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 67.742657][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 67.748464][ T21] ret_from_fork+0x1f/0x30 [ 67.754595][ T21] Kernel Offset: disabled [ 67.760335][ T21] Rebooting in 86400 seconds..