[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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 '10.128.10.61' (ECDSA) to the list of known hosts. 2020/06/19 03:48:49 fuzzer started 2020/06/19 03:48:49 connecting to host at 10.128.0.26:37047 2020/06/19 03:48:49 checking machine... 2020/06/19 03:48:49 checking revisions... 2020/06/19 03:48:49 testing simple program... syzkaller login: [ 61.662852][ T6851] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 03:48:50 building call list... [ 62.036308][ T148] tipc: TX() has been purged, node left! [ 62.548646][ T148] ================================================================== [ 62.556985][ T148] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.564905][ T148] Write of size 1 at addr ffff8880a00001e4 by task kworker/u4:3/148 [ 62.572867][ T148] [ 62.575202][ T148] CPU: 0 PID: 148 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.583513][ T148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.593568][ T148] Workqueue: netns cleanup_net [ 62.598323][ T148] Call Trace: [ 62.601616][ T148] dump_stack+0x18f/0x20d [ 62.605948][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.611487][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.617044][ T148] ? afs_put_call+0xa40/0xa40 [ 62.621726][ T148] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.628852][ T148] ? vprintk_func+0x97/0x1a6 [ 62.633450][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.639026][ T148] kasan_report.cold+0x1f/0x37 [ 62.643789][ T148] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.649416][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.655075][ T148] afs_wake_up_async_call+0x6aa/0x770 [ 62.660439][ T148] ? afs_close_socket+0x320/0x320 [ 62.665477][ T148] ? afs_put_call+0xa40/0xa40 [ 62.670151][ T148] rxrpc_notify_socket+0x1db/0x5d0 [ 62.675266][ T148] ? afs_put_call+0xa40/0xa40 [ 62.679941][ T148] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.686364][ T148] rxrpc_call_completed+0xca/0xf0 [ 62.691406][ T148] rxrpc_discard_prealloc+0x781/0xab0 [ 62.696956][ T148] ? lock_sock_nested+0x94/0x110 [ 62.701894][ T148] rxrpc_listen+0x147/0x360 [ 62.706450][ T148] afs_close_socket+0x95/0x320 [ 62.711208][ T148] ? afs_purge_servers+0x16d/0x300 [ 62.716332][ T148] ? afs_rx_discard_new_call+0x50/0x50 [ 62.721800][ T148] ? init_wait_var_entry+0x200/0x200 [ 62.727176][ T148] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.732895][ T148] ? check_preemption_disabled+0x38/0x220 [ 62.738626][ T148] afs_net_exit+0x1bc/0x310 [ 62.743132][ T148] ? afs_net_init+0xe30/0xe30 [ 62.747820][ T148] ops_exit_list.isra.0+0xa8/0x150 [ 62.752947][ T148] cleanup_net+0x511/0xa50 [ 62.757403][ T148] ? unregister_pernet_device+0x70/0x70 [ 62.762955][ T148] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.768940][ T148] process_one_work+0x965/0x1690 [ 62.773888][ T148] ? lock_release+0x800/0x800 [ 62.778571][ T148] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.783943][ T148] ? rwlock_bug.part.0+0x90/0x90 [ 62.788890][ T148] worker_thread+0x96/0xe10 [ 62.793410][ T148] ? process_one_work+0x1690/0x1690 [ 62.798611][ T148] kthread+0x3b5/0x4a0 [ 62.802684][ T148] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.808419][ T148] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.814146][ T148] ret_from_fork+0x1f/0x30 [ 62.818570][ T148] [ 62.820892][ T148] Allocated by task 6851: [ 62.825217][ T148] save_stack+0x1b/0x40 [ 62.829372][ T148] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.835016][ T148] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.840509][ T148] afs_alloc_call+0x55/0x630 [ 62.845353][ T148] afs_charge_preallocation+0xe9/0x2d0 [ 62.850803][ T148] afs_open_socket+0x292/0x360 [ 62.855563][ T148] afs_net_init+0xa6c/0xe30 [ 62.860057][ T148] ops_init+0xaf/0x420 [ 62.864117][ T148] setup_net+0x2de/0x860 [ 62.868354][ T148] copy_net_ns+0x293/0x590 [ 62.872773][ T148] create_new_namespaces+0x3fb/0xb30 [ 62.878052][ T148] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.883678][ T148] ksys_unshare+0x43d/0x8e0 [ 62.888175][ T148] __x64_sys_unshare+0x2d/0x40 [ 62.892932][ T148] do_syscall_64+0x60/0xe0 [ 62.897433][ T148] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.903311][ T148] [ 62.905641][ T148] Freed by task 148: [ 62.909545][ T148] save_stack+0x1b/0x40 [ 62.913703][ T148] __kasan_slab_free+0xf7/0x140 [ 62.918552][ T148] kfree+0x109/0x2b0 [ 62.922442][ T148] afs_put_call+0x585/0xa40 [ 62.927035][ T148] rxrpc_discard_prealloc+0x764/0xab0 [ 62.932427][ T148] rxrpc_listen+0x147/0x360 [ 62.936958][ T148] afs_close_socket+0x95/0x320 [ 62.941758][ T148] afs_net_exit+0x1bc/0x310 [ 62.946292][ T148] ops_exit_list.isra.0+0xa8/0x150 [ 62.951419][ T148] cleanup_net+0x511/0xa50 [ 62.955831][ T148] process_one_work+0x965/0x1690 [ 62.960773][ T148] worker_thread+0x96/0xe10 [ 62.965275][ T148] kthread+0x3b5/0x4a0 [ 62.969605][ T148] ret_from_fork+0x1f/0x30 [ 62.974008][ T148] [ 62.976429][ T148] The buggy address belongs to the object at ffff8880a0000000 [ 62.976429][ T148] which belongs to the cache kmalloc-1k of size 1024 [ 62.990575][ T148] The buggy address is located 484 bytes inside of [ 62.990575][ T148] 1024-byte region [ffff8880a0000000, ffff8880a0000400) [ 63.003929][ T148] The buggy address belongs to the page: [ 63.009566][ T148] page:ffffea0002800000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 63.018673][ T148] flags: 0xfffe0000000200(slab) [ 63.023529][ T148] raw: 00fffe0000000200 ffffea000281fb08 ffffea000281fbc8 ffff8880aa000c40 [ 63.032141][ T148] raw: 0000000000000000 ffff8880a0000000 0000000100000002 0000000000000000 [ 63.040733][ T148] page dumped because: kasan: bad access detected [ 63.047134][ T148] [ 63.049478][ T148] Memory state around the buggy address: [ 63.055109][ T148] ffff8880a0000080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.063173][ T148] ffff8880a0000100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.071251][ T148] >ffff8880a0000180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.079408][ T148] ^ [ 63.086685][ T148] ffff8880a0000200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.094949][ T148] ffff8880a0000280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 63.103000][ T148] ================================================================== [ 63.111052][ T148] Disabling lock debugging due to kernel taint [ 63.117256][ T148] Kernel panic - not syncing: panic_on_warn set ... [ 63.123865][ T148] CPU: 0 PID: 148 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 63.133621][ T148] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 63.143688][ T148] Workqueue: netns cleanup_net [ 63.148455][ T148] Call Trace: [ 63.151754][ T148] dump_stack+0x18f/0x20d [ 63.156102][ T148] ? afs_wake_up_async_call+0x670/0x770 [ 63.161661][ T148] ? afs_put_call+0xa40/0xa40 [ 63.166341][ T148] panic+0x2e3/0x75c [ 63.170236][ T148] ? __warn_printk+0xf3/0xf3 [ 63.174820][ T148] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 63.181216][ T148] ? trace_hardirqs_on+0x55/0x220 [ 63.186592][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.192116][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.197648][ T148] ? afs_put_call+0xa40/0xa40 [ 63.202322][ T148] end_report+0x4d/0x53 [ 63.206465][ T148] kasan_report.cold+0xd/0x37 [ 63.211139][ T148] ? rcu_read_lock_held_common+0x51/0xa0 [ 63.216762][ T148] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.222325][ T148] afs_wake_up_async_call+0x6aa/0x770 [ 63.227701][ T148] ? afs_close_socket+0x320/0x320 [ 63.232796][ T148] ? afs_put_call+0xa40/0xa40 [ 63.237460][ T148] rxrpc_notify_socket+0x1db/0x5d0 [ 63.242578][ T148] ? afs_put_call+0xa40/0xa40 [ 63.247271][ T148] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.253676][ T148] rxrpc_call_completed+0xca/0xf0 [ 63.258826][ T148] rxrpc_discard_prealloc+0x781/0xab0 [ 63.264290][ T148] ? lock_sock_nested+0x94/0x110 [ 63.269313][ T148] rxrpc_listen+0x147/0x360 [ 63.274104][ T148] afs_close_socket+0x95/0x320 [ 63.278872][ T148] ? afs_purge_servers+0x16d/0x300 [ 63.283974][ T148] ? afs_rx_discard_new_call+0x50/0x50 [ 63.289431][ T148] ? init_wait_var_entry+0x200/0x200 [ 63.294792][ T148] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.300424][ T148] ? check_preemption_disabled+0x38/0x220 [ 63.306328][ T148] afs_net_exit+0x1bc/0x310 [ 63.311073][ T148] ? afs_net_init+0xe30/0xe30 [ 63.316133][ T148] ops_exit_list.isra.0+0xa8/0x150 [ 63.321260][ T148] cleanup_net+0x511/0xa50 [ 63.325674][ T148] ? unregister_pernet_device+0x70/0x70 [ 63.331225][ T148] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.337218][ T148] process_one_work+0x965/0x1690 [ 63.342172][ T148] ? lock_release+0x800/0x800 [ 63.346845][ T148] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.352216][ T148] ? rwlock_bug.part.0+0x90/0x90 [ 63.357161][ T148] worker_thread+0x96/0xe10 [ 63.361679][ T148] ? process_one_work+0x1690/0x1690 [ 63.367222][ T148] kthread+0x3b5/0x4a0 [ 63.371285][ T148] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.377116][ T148] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.382967][ T148] ret_from_fork+0x1f/0x30 [ 63.389126][ T148] Kernel Offset: disabled [ 63.393487][ T148] Rebooting in 86400 seconds..