[ OK ] Started Getty on tty6. [ OK ] Started Getty on tty5. [ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ 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 '10.128.0.151' (ECDSA) to the list of known hosts. 2020/06/19 00:46:31 fuzzer started 2020/06/19 00:46:32 connecting to host at 10.128.0.26:34707 2020/06/19 00:46:32 checking machine... 2020/06/19 00:46:32 checking revisions... 2020/06/19 00:46:32 testing simple program... syzkaller login: [ 59.997936][ T6822] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 00:46:32 building call list... [ 60.319896][ T21] tipc: TX() has been purged, node left! [ 60.832042][ T21] ================================================================== [ 60.840321][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 60.848220][ T21] Write of size 1 at addr ffff8880a6e5e1e4 by task kworker/u4:1/21 [ 60.856092][ T21] [ 60.858423][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.866664][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.876720][ T21] Workqueue: netns cleanup_net [ 60.881491][ T21] Call Trace: [ 60.884783][ T21] dump_stack+0x18f/0x20d [ 60.889132][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.894670][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.900208][ T21] ? afs_put_call+0xa40/0xa40 [ 60.904888][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 60.911913][ T21] ? vprintk_func+0x97/0x1a6 [ 60.916505][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.922047][ T21] kasan_report.cold+0x1f/0x37 [ 60.926819][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 60.932445][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.937997][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 60.943363][ T21] ? afs_close_socket+0x320/0x320 [ 60.948469][ T21] ? afs_put_call+0xa40/0xa40 [ 60.953340][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 60.958464][ T21] ? afs_put_call+0xa40/0xa40 [ 60.963158][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.969587][ T21] rxrpc_call_completed+0xca/0xf0 [ 60.974623][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 60.979998][ T21] ? lock_sock_nested+0x94/0x110 [ 60.984935][ T21] rxrpc_listen+0x147/0x360 [ 60.989438][ T21] afs_close_socket+0x95/0x320 [ 60.994200][ T21] ? afs_purge_servers+0x16d/0x300 [ 60.999325][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 61.004793][ T21] ? init_wait_var_entry+0x200/0x200 [ 61.010081][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.015710][ T21] ? check_preemption_disabled+0x38/0x220 [ 61.021431][ T21] afs_net_exit+0x1bc/0x310 [ 61.025940][ T21] ? afs_net_init+0xe30/0xe30 [ 61.030615][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.035730][ T21] cleanup_net+0x511/0xa50 [ 61.040410][ T21] ? unregister_pernet_device+0x70/0x70 [ 61.045958][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.051943][ T21] process_one_work+0x965/0x1690 [ 61.056888][ T21] ? lock_release+0x800/0x800 [ 61.061566][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.066964][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 61.071917][ T21] worker_thread+0x96/0xe10 [ 61.076437][ T21] ? process_one_work+0x1690/0x1690 [ 61.081638][ T21] kthread+0x3b5/0x4a0 [ 61.085706][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.091424][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.097152][ T21] ret_from_fork+0x1f/0x30 [ 61.101577][ T21] [ 61.103899][ T21] Allocated by task 6822: [ 61.108227][ T21] save_stack+0x1b/0x40 [ 61.112380][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.118093][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.123479][ T21] afs_alloc_call+0x55/0x630 [ 61.128071][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 61.133528][ T21] afs_open_socket+0x292/0x360 [ 61.138287][ T21] afs_net_init+0xa6c/0xe30 [ 61.142793][ T21] ops_init+0xaf/0x420 [ 61.146854][ T21] setup_net+0x2de/0x860 [ 61.151089][ T21] copy_net_ns+0x293/0x590 [ 61.155505][ T21] create_new_namespaces+0x3fb/0xb30 [ 61.160829][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.166457][ T21] ksys_unshare+0x43d/0x8e0 [ 61.170958][ T21] __x64_sys_unshare+0x2d/0x40 [ 61.175718][ T21] do_syscall_64+0x60/0xe0 [ 61.180136][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.186021][ T21] [ 61.188343][ T21] Freed by task 21: [ 61.192149][ T21] save_stack+0x1b/0x40 [ 61.196299][ T21] __kasan_slab_free+0xf7/0x140 [ 61.201144][ T21] kfree+0x109/0x2b0 [ 61.205041][ T21] afs_put_call+0x585/0xa40 [ 61.209551][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 61.214921][ T21] rxrpc_listen+0x147/0x360 [ 61.219422][ T21] afs_close_socket+0x95/0x320 [ 61.224184][ T21] afs_net_exit+0x1bc/0x310 [ 61.228680][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.233782][ T21] cleanup_net+0x511/0xa50 [ 61.238192][ T21] process_one_work+0x965/0x1690 [ 61.243127][ T21] worker_thread+0x96/0xe10 [ 61.247623][ T21] kthread+0x3b5/0x4a0 [ 61.251686][ T21] ret_from_fork+0x1f/0x30 [ 61.256093][ T21] [ 61.258423][ T21] The buggy address belongs to the object at ffff8880a6e5e000 [ 61.258423][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 61.272469][ T21] The buggy address is located 484 bytes inside of [ 61.272469][ T21] 1024-byte region [ffff8880a6e5e000, ffff8880a6e5e400) [ 61.286249][ T21] The buggy address belongs to the page: [ 61.291883][ T21] page:ffffea00029b9780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.300988][ T21] flags: 0xfffe0000000200(slab) [ 61.306020][ T21] raw: 00fffe0000000200 ffffea0002623d88 ffffea00024fa588 ffff8880aa000c40 [ 61.314601][ T21] raw: 0000000000000000 ffff8880a6e5e000 0000000100000002 0000000000000000 [ 61.323171][ T21] page dumped because: kasan: bad access detected [ 61.329569][ T21] [ 61.331888][ T21] Memory state around the buggy address: [ 61.337512][ T21] ffff8880a6e5e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.345568][ T21] ffff8880a6e5e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.353625][ T21] >ffff8880a6e5e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.361679][ T21] ^ [ 61.368873][ T21] ffff8880a6e5e200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.377019][ T21] ffff8880a6e5e280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.385095][ T21] ================================================================== [ 61.393250][ T21] Disabling lock debugging due to kernel taint [ 61.399530][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 61.406118][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.415735][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.425828][ T21] Workqueue: netns cleanup_net [ 61.430714][ T21] Call Trace: [ 61.434132][ T21] dump_stack+0x18f/0x20d [ 61.438490][ T21] ? afs_wake_up_async_call+0x670/0x770 [ 61.444593][ T21] ? afs_put_call+0xa40/0xa40 [ 61.449274][ T21] panic+0x2e3/0x75c [ 61.453179][ T21] ? __warn_printk+0xf3/0xf3 [ 61.457770][ T21] ? asm_common_interrupt+0x1e/0x40 [ 61.462974][ T21] ? trace_hardirqs_on+0x55/0x220 [ 61.467997][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.473543][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.479094][ T21] ? afs_put_call+0xa40/0xa40 [ 61.483767][ T21] end_report+0x4d/0x53 [ 61.487923][ T21] kasan_report.cold+0xd/0x37 [ 61.492598][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.498227][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.503916][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 61.509282][ T21] ? afs_close_socket+0x320/0x320 [ 61.514299][ T21] ? afs_put_call+0xa40/0xa40 [ 61.518993][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 61.524104][ T21] ? afs_put_call+0xa40/0xa40 [ 61.528772][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.535181][ T21] rxrpc_call_completed+0xca/0xf0 [ 61.540205][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 61.545575][ T21] ? lock_sock_nested+0x94/0x110 [ 61.550594][ T21] rxrpc_listen+0x147/0x360 [ 61.555092][ T21] afs_close_socket+0x95/0x320 [ 61.559847][ T21] ? afs_purge_servers+0x16d/0x300 [ 61.564953][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 61.570408][ T21] ? init_wait_var_entry+0x200/0x200 [ 61.575727][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.581354][ T21] ? check_preemption_disabled+0x38/0x220 [ 61.587151][ T21] afs_net_exit+0x1bc/0x310 [ 61.591648][ T21] ? afs_net_init+0xe30/0xe30 [ 61.596597][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 61.601846][ T21] cleanup_net+0x511/0xa50 [ 61.606258][ T21] ? unregister_pernet_device+0x70/0x70 [ 61.613883][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.619861][ T21] process_one_work+0x965/0x1690 [ 61.624795][ T21] ? lock_release+0x800/0x800 [ 61.629462][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.634824][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 61.639756][ T21] worker_thread+0x96/0xe10 [ 61.644254][ T21] ? process_one_work+0x1690/0x1690 [ 61.649440][ T21] kthread+0x3b5/0x4a0 [ 61.653500][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.659208][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.665016][ T21] ret_from_fork+0x1f/0x30 [ 61.670736][ T21] Kernel Offset: disabled [ 61.675057][ T21] Rebooting in 86400 seconds..