[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.21' (ECDSA) to the list of known hosts. 2020/06/18 08:53:08 fuzzer started 2020/06/18 08:53:08 connecting to host at 10.128.0.26:42773 2020/06/18 08:53:08 checking machine... 2020/06/18 08:53:08 checking revisions... 2020/06/18 08:53:08 testing simple program... syzkaller login: [ 61.502299][ T6853] IPVS: ftp: loaded support on port[0] = 21 2020/06/18 08:53:08 building call list... [ 61.845850][ T258] tipc: TX() has been purged, node left! [ 62.379155][ T258] ================================================================== [ 62.387409][ T258] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.395295][ T258] Write of size 1 at addr ffff888081fbb9e4 by task kworker/u4:6/258 [ 62.403258][ T258] [ 62.405587][ T258] CPU: 0 PID: 258 Comm: kworker/u4:6 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.413901][ T258] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.423965][ T258] Workqueue: netns cleanup_net [ 62.428720][ T258] Call Trace: [ 62.432031][ T258] dump_stack+0x18f/0x20d [ 62.436362][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.441908][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.447447][ T258] ? afs_put_call+0xa40/0xa40 [ 62.452133][ T258] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.459163][ T258] ? vprintk_func+0x97/0x1a6 [ 62.463759][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.469303][ T258] kasan_report.cold+0x1f/0x37 [ 62.474072][ T258] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.479698][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.485243][ T258] afs_wake_up_async_call+0x6aa/0x770 [ 62.490611][ T258] ? afs_close_socket+0x320/0x320 [ 62.495635][ T258] ? afs_put_call+0xa40/0xa40 [ 62.500399][ T258] rxrpc_notify_socket+0x1db/0x5d0 [ 62.505511][ T258] ? afs_put_call+0xa40/0xa40 [ 62.510186][ T258] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.516601][ T258] rxrpc_call_completed+0xca/0xf0 [ 62.521629][ T258] rxrpc_discard_prealloc+0x781/0xab0 [ 62.527002][ T258] ? lock_sock_nested+0x94/0x110 [ 62.531942][ T258] rxrpc_listen+0x147/0x360 [ 62.536447][ T258] afs_close_socket+0x95/0x320 [ 62.541209][ T258] ? afs_purge_servers+0x16d/0x300 [ 62.546320][ T258] ? afs_rx_discard_new_call+0x50/0x50 [ 62.551782][ T258] ? init_wait_var_entry+0x200/0x200 [ 62.557081][ T258] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.562797][ T258] ? check_preemption_disabled+0x38/0x220 [ 62.568519][ T258] afs_net_exit+0x1bc/0x310 [ 62.573025][ T258] ? afs_net_init+0xe30/0xe30 [ 62.577701][ T258] ops_exit_list.isra.0+0xa8/0x150 [ 62.582816][ T258] cleanup_net+0x511/0xa50 [ 62.587256][ T258] ? unregister_pernet_device+0x70/0x70 [ 62.592804][ T258] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.598808][ T258] process_one_work+0x965/0x1690 [ 62.603755][ T258] ? lock_release+0x800/0x800 [ 62.608432][ T258] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.613809][ T258] ? rwlock_bug.part.0+0x90/0x90 [ 62.618758][ T258] worker_thread+0x96/0xe10 [ 62.623279][ T258] ? process_one_work+0x1690/0x1690 [ 62.628481][ T258] kthread+0x3b5/0x4a0 [ 62.632564][ T258] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.638282][ T258] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.644001][ T258] ret_from_fork+0x1f/0x30 [ 62.648426][ T258] [ 62.650811][ T258] Allocated by task 6853: [ 62.655139][ T258] save_stack+0x1b/0x40 [ 62.659291][ T258] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.664935][ T258] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.670304][ T258] afs_alloc_call+0x55/0x630 [ 62.674891][ T258] afs_charge_preallocation+0xe9/0x2d0 [ 62.680345][ T258] afs_open_socket+0x292/0x360 [ 62.685116][ T258] afs_net_init+0xa6c/0xe30 [ 62.689610][ T258] ops_init+0xaf/0x420 [ 62.693759][ T258] setup_net+0x2de/0x860 [ 62.697995][ T258] copy_net_ns+0x293/0x590 [ 62.702408][ T258] create_new_namespaces+0x3fb/0xb30 [ 62.707690][ T258] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.713319][ T258] ksys_unshare+0x43d/0x8e0 [ 62.717828][ T258] __x64_sys_unshare+0x2d/0x40 [ 62.722587][ T258] do_syscall_64+0x60/0xe0 [ 62.727000][ T258] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.732877][ T258] [ 62.735198][ T258] Freed by task 258: [ 62.739090][ T258] save_stack+0x1b/0x40 [ 62.743241][ T258] __kasan_slab_free+0xf7/0x140 [ 62.748105][ T258] kfree+0x109/0x2b0 [ 62.752001][ T258] afs_put_call+0x585/0xa40 [ 62.756504][ T258] rxrpc_discard_prealloc+0x764/0xab0 [ 62.761870][ T258] rxrpc_listen+0x147/0x360 [ 62.766371][ T258] afs_close_socket+0x95/0x320 [ 62.771128][ T258] afs_net_exit+0x1bc/0x310 [ 62.775628][ T258] ops_exit_list.isra.0+0xa8/0x150 [ 62.780737][ T258] cleanup_net+0x511/0xa50 [ 62.785154][ T258] process_one_work+0x965/0x1690 [ 62.790086][ T258] worker_thread+0x96/0xe10 [ 62.794610][ T258] kthread+0x3b5/0x4a0 [ 62.798677][ T258] ret_from_fork+0x1f/0x30 [ 62.803079][ T258] [ 62.805405][ T258] The buggy address belongs to the object at ffff888081fbb800 [ 62.805405][ T258] which belongs to the cache kmalloc-1k of size 1024 [ 62.819451][ T258] The buggy address is located 484 bytes inside of [ 62.819451][ T258] 1024-byte region [ffff888081fbb800, ffff888081fbbc00) [ 62.833055][ T258] The buggy address belongs to the page: [ 62.838690][ T258] page:ffffea000207eec0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.847790][ T258] flags: 0xfffe0000000200(slab) [ 62.852646][ T258] raw: 00fffe0000000200 ffffea000207ee48 ffffea000207ef48 ffff8880aa000c40 [ 62.861229][ T258] raw: 0000000000000000 ffff888081fbb000 0000000100000002 0000000000000000 [ 62.869808][ T258] page dumped because: kasan: bad access detected [ 62.876212][ T258] [ 62.878540][ T258] Memory state around the buggy address: [ 62.884188][ T258] ffff888081fbb880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.892257][ T258] ffff888081fbb900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.900318][ T258] >ffff888081fbb980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.908503][ T258] ^ [ 62.915699][ T258] ffff888081fbba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.924284][ T258] ffff888081fbba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.932361][ T258] ================================================================== [ 62.940411][ T258] Disabling lock debugging due to kernel taint [ 62.946620][ T258] Kernel panic - not syncing: panic_on_warn set ... [ 62.953209][ T258] CPU: 0 PID: 258 Comm: kworker/u4:6 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.962913][ T258] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.972991][ T258] Workqueue: netns cleanup_net [ 62.977751][ T258] Call Trace: [ 62.981040][ T258] dump_stack+0x18f/0x20d [ 62.985382][ T258] ? afs_wake_up_async_call+0x680/0x770 [ 62.991273][ T258] ? afs_put_call+0xa40/0xa40 [ 62.995954][ T258] panic+0x2e3/0x75c [ 62.999854][ T258] ? __warn_printk+0xf3/0xf3 [ 63.004450][ T258] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.010632][ T258] ? trace_hardirqs_on+0x55/0x220 [ 63.016609][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.022152][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.027716][ T258] ? afs_put_call+0xa40/0xa40 [ 63.032395][ T258] end_report+0x4d/0x53 [ 63.036543][ T258] kasan_report.cold+0xd/0x37 [ 63.041215][ T258] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.046842][ T258] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.052376][ T258] afs_wake_up_async_call+0x6aa/0x770 [ 63.058318][ T258] ? afs_close_socket+0x320/0x320 [ 63.063429][ T258] ? afs_put_call+0xa40/0xa40 [ 63.068101][ T258] rxrpc_notify_socket+0x1db/0x5d0 [ 63.073273][ T258] ? afs_put_call+0xa40/0xa40 [ 63.077943][ T258] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.084359][ T258] rxrpc_call_completed+0xca/0xf0 [ 63.089465][ T258] rxrpc_discard_prealloc+0x781/0xab0 [ 63.094835][ T258] ? lock_sock_nested+0x94/0x110 [ 63.099756][ T258] rxrpc_listen+0x147/0x360 [ 63.104248][ T258] afs_close_socket+0x95/0x320 [ 63.109003][ T258] ? afs_purge_servers+0x16d/0x300 [ 63.114101][ T258] ? afs_rx_discard_new_call+0x50/0x50 [ 63.119604][ T258] ? init_wait_var_entry+0x200/0x200 [ 63.124971][ T258] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.130604][ T258] ? check_preemption_disabled+0x38/0x220 [ 63.136314][ T258] afs_net_exit+0x1bc/0x310 [ 63.140846][ T258] ? afs_net_init+0xe30/0xe30 [ 63.145511][ T258] ops_exit_list.isra.0+0xa8/0x150 [ 63.150618][ T258] cleanup_net+0x511/0xa50 [ 63.155019][ T258] ? unregister_pernet_device+0x70/0x70 [ 63.160559][ T258] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.166532][ T258] process_one_work+0x965/0x1690 [ 63.171471][ T258] ? lock_release+0x800/0x800 [ 63.176142][ T258] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.181498][ T258] ? rwlock_bug.part.0+0x90/0x90 [ 63.186433][ T258] worker_thread+0x96/0xe10 [ 63.190933][ T258] ? process_one_work+0x1690/0x1690 [ 63.196120][ T258] kthread+0x3b5/0x4a0 [ 63.200172][ T258] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.205890][ T258] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.211601][ T258] ret_from_fork+0x1f/0x30 [ 63.217538][ T258] Kernel Offset: disabled [ 63.221856][ T258] Rebooting in 86400 seconds..