[ 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 '10.128.0.212' (ECDSA) to the list of known hosts. 2020/06/16 03:51:59 fuzzer started 2020/06/16 03:51:59 connecting to host at 10.128.0.26:39597 2020/06/16 03:51:59 checking machine... 2020/06/16 03:51:59 checking revisions... 2020/06/16 03:51:59 testing simple program... syzkaller login: [ 61.464009][ T6811] IPVS: ftp: loaded support on port[0] = 21 2020/06/16 03:51:59 building call list... [ 61.784037][ T21] tipc: TX() has been purged, node left! [ 62.286278][ T21] ================================================================== [ 62.294532][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.302415][ T21] Write of size 1 at addr ffff8880a90ed1e4 by task kworker/u4:1/21 [ 62.310308][ T21] [ 62.312636][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-next-20200615-syzkaller #0 [ 62.322077][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.332135][ T21] Workqueue: netns cleanup_net [ 62.336885][ T21] Call Trace: [ 62.340179][ T21] dump_stack+0x18f/0x20d [ 62.344511][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.350051][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.355594][ T21] ? afs_put_call+0xa40/0xa40 [ 62.360278][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.367327][ T21] ? vprintk_func+0x97/0x1a6 [ 62.371919][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.377460][ T21] kasan_report.cold+0x1f/0x37 [ 62.382227][ T21] ? rcu_read_lock_held_common+0x71/0xa0 [ 62.387852][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.393397][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.398782][ T21] ? afs_close_socket+0x320/0x320 [ 62.403810][ T21] ? afs_put_call+0xa40/0xa40 [ 62.408484][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.413615][ T21] ? afs_put_call+0xa40/0xa40 [ 62.418291][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.424708][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.429822][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 62.435195][ T21] ? lock_sock_nested+0x94/0x110 [ 62.440132][ T21] rxrpc_listen+0x147/0x360 [ 62.444638][ T21] afs_close_socket+0x95/0x320 [ 62.449400][ T21] ? afs_purge_servers+0x16d/0x300 [ 62.454510][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.459970][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.465257][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.470890][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.476644][ T21] afs_net_exit+0x1bc/0x310 [ 62.481144][ T21] ? afs_net_init+0xe30/0xe30 [ 62.485834][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.490948][ T21] cleanup_net+0x511/0xa50 [ 62.495367][ T21] ? unregister_pernet_device+0x70/0x70 [ 62.500919][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.506916][ T21] process_one_work+0x965/0x1690 [ 62.511863][ T21] ? lock_release+0x800/0x800 [ 62.516546][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.521919][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.526871][ T21] worker_thread+0x96/0xe10 [ 62.531386][ T21] ? process_one_work+0x1690/0x1690 [ 62.536627][ T21] kthread+0x3b5/0x4a0 [ 62.540739][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.546460][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.552183][ T21] ret_from_fork+0x1f/0x30 [ 62.556606][ T21] [ 62.558928][ T21] Allocated by task 6811: [ 62.563255][ T21] save_stack+0x1b/0x40 [ 62.567419][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.573053][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.578422][ T21] afs_alloc_call+0x55/0x630 [ 62.583005][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 62.588455][ T21] afs_open_socket+0x292/0x360 [ 62.593210][ T21] afs_net_init+0xa6c/0xe30 [ 62.597705][ T21] ops_init+0xaf/0x420 [ 62.601764][ T21] setup_net+0x2de/0x860 [ 62.605999][ T21] copy_net_ns+0x293/0x590 [ 62.610409][ T21] create_new_namespaces+0x3fb/0xb30 [ 62.615687][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.621315][ T21] ksys_unshare+0x43d/0x8e0 [ 62.625814][ T21] __x64_sys_unshare+0x2d/0x40 [ 62.630575][ T21] do_syscall_64+0x60/0xe0 [ 62.634985][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.640859][ T21] [ 62.643176][ T21] Freed by task 21: [ 62.646977][ T21] save_stack+0x1b/0x40 [ 62.651128][ T21] __kasan_slab_free+0xf7/0x140 [ 62.655973][ T21] kfree+0x109/0x2b0 [ 62.659864][ T21] afs_put_call+0x585/0xa40 [ 62.664384][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 62.669748][ T21] rxrpc_listen+0x147/0x360 [ 62.674255][ T21] afs_close_socket+0x95/0x320 [ 62.679022][ T21] afs_net_exit+0x1bc/0x310 [ 62.683547][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.688657][ T21] cleanup_net+0x511/0xa50 [ 62.693075][ T21] process_one_work+0x965/0x1690 [ 62.698008][ T21] worker_thread+0x96/0xe10 [ 62.702513][ T21] kthread+0x3b5/0x4a0 [ 62.706585][ T21] ret_from_fork+0x1f/0x30 [ 62.711003][ T21] [ 62.713334][ T21] The buggy address belongs to the object at ffff8880a90ed000 [ 62.713334][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 62.727396][ T21] The buggy address is located 484 bytes inside of [ 62.727396][ T21] 1024-byte region [ffff8880a90ed000, ffff8880a90ed400) [ 62.740743][ T21] The buggy address belongs to the page: [ 62.746371][ T21] page:ffffea0002a43b40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.755469][ T21] flags: 0xfffe0000000200(slab) [ 62.760327][ T21] raw: 00fffe0000000200 ffffea0002a458c8 ffffea00023fe448 ffff8880aa000c40 [ 62.768925][ T21] raw: 0000000000000000 ffff8880a90ed000 0000000100000002 0000000000000000 [ 62.777509][ T21] page dumped because: kasan: bad access detected [ 62.783912][ T21] [ 62.786236][ T21] Memory state around the buggy address: [ 62.791861][ T21] ffff8880a90ed080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.799916][ T21] ffff8880a90ed100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.807988][ T21] >ffff8880a90ed180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.816044][ T21] ^ [ 62.823233][ T21] ffff8880a90ed200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.831289][ T21] ffff8880a90ed280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.839514][ T21] ================================================================== [ 62.847561][ T21] Disabling lock debugging due to kernel taint [ 62.853763][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 62.860348][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-next-20200615-syzkaller #0 [ 62.871178][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.881240][ T21] Workqueue: netns cleanup_net [ 62.886000][ T21] Call Trace: [ 62.889286][ T21] dump_stack+0x18f/0x20d [ 62.893616][ T21] ? afs_wake_up_async_call+0x660/0x770 [ 62.899165][ T21] ? afs_put_call+0xa40/0xa40 [ 62.903835][ T21] panic+0x2e3/0x75c [ 62.907733][ T21] ? __warn_printk+0xf3/0xf3 [ 62.912325][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.918507][ T21] ? trace_hardirqs_on+0x55/0x220 [ 62.923528][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.929079][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.934646][ T21] ? afs_put_call+0xa40/0xa40 [ 62.939321][ T21] end_report+0x4d/0x53 [ 62.943468][ T21] kasan_report.cold+0xd/0x37 [ 62.948140][ T21] ? rcu_read_lock_held_common+0x71/0xa0 [ 62.953763][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.959322][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.964695][ T21] ? afs_close_socket+0x320/0x320 [ 62.969710][ T21] ? afs_put_call+0xa40/0xa40 [ 62.974377][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.979484][ T21] ? afs_put_call+0xa40/0xa40 [ 62.984163][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.990582][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.995613][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 63.000980][ T21] ? lock_sock_nested+0x94/0x110 [ 63.005910][ T21] rxrpc_listen+0x147/0x360 [ 63.010418][ T21] afs_close_socket+0x95/0x320 [ 63.015175][ T21] ? afs_purge_servers+0x16d/0x300 [ 63.020279][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 63.025740][ T21] ? init_wait_var_entry+0x200/0x200 [ 63.031021][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.036643][ T21] ? check_preemption_disabled+0x38/0x220 [ 63.042356][ T21] afs_net_exit+0x1bc/0x310 [ 63.046851][ T21] ? afs_net_init+0xe30/0xe30 [ 63.051525][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 63.056632][ T21] cleanup_net+0x511/0xa50 [ 63.061039][ T21] ? unregister_pernet_device+0x70/0x70 [ 63.066598][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.072572][ T21] process_one_work+0x965/0x1690 [ 63.077504][ T21] ? lock_release+0x800/0x800 [ 63.082171][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.087533][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 63.092467][ T21] worker_thread+0x96/0xe10 [ 63.096968][ T21] ? process_one_work+0x1690/0x1690 [ 63.102157][ T21] kthread+0x3b5/0x4a0 [ 63.106216][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.112183][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.117893][ T21] ret_from_fork+0x1f/0x30 [ 63.123710][ T21] Kernel Offset: disabled [ 63.128141][ T21] Rebooting in 86400 seconds..