[ 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 '10.128.1.5' (ECDSA) to the list of known hosts. 2020/06/19 02:07:18 fuzzer started 2020/06/19 02:07:18 connecting to host at 10.128.0.26:37341 2020/06/19 02:07:18 checking machine... 2020/06/19 02:07:18 checking revisions... 2020/06/19 02:07:18 testing simple program... syzkaller login: [ 64.739507][ T6803] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 02:07:19 building call list... [ 65.078207][ T127] tipc: TX() has been purged, node left! [ 65.630681][ T127] ================================================================== [ 65.640084][ T127] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 65.648258][ T127] Write of size 1 at addr ffff8880a62d31e4 by task kworker/u4:4/127 [ 65.656252][ T127] [ 65.658762][ T127] CPU: 0 PID: 127 Comm: kworker/u4:4 Not tainted 5.8.0-rc1-syzkaller #0 [ 65.668564][ T127] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.680304][ T127] Workqueue: netns cleanup_net [ 65.685147][ T127] Call Trace: [ 65.688443][ T127] dump_stack+0x18f/0x20d [ 65.692956][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.698696][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.704256][ T127] ? afs_put_call+0xa40/0xa40 [ 65.708938][ T127] print_address_description.constprop.0.cold+0xd3/0x413 [ 65.716159][ T127] ? vprintk_func+0x97/0x1a6 [ 65.720772][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.726315][ T127] kasan_report.cold+0x1f/0x37 [ 65.731086][ T127] ? rcu_read_lock_held_common+0x51/0xa0 [ 65.736725][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.742294][ T127] afs_wake_up_async_call+0x6aa/0x770 [ 65.747688][ T127] ? afs_close_socket+0x320/0x320 [ 65.752769][ T127] ? afs_put_call+0xa40/0xa40 [ 65.757579][ T127] rxrpc_notify_socket+0x1db/0x5d0 [ 65.764732][ T127] ? afs_put_call+0xa40/0xa40 [ 65.769733][ T127] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 65.776756][ T127] rxrpc_call_completed+0xca/0xf0 [ 65.782457][ T127] rxrpc_discard_prealloc+0x781/0xab0 [ 65.788225][ T127] ? lock_sock_nested+0x94/0x110 [ 65.793192][ T127] rxrpc_listen+0x147/0x360 [ 65.797872][ T127] afs_close_socket+0x95/0x320 [ 65.802658][ T127] ? afs_purge_servers+0x16d/0x300 [ 65.807770][ T127] ? afs_rx_discard_new_call+0x50/0x50 [ 65.813233][ T127] ? init_wait_var_entry+0x200/0x200 [ 65.818521][ T127] ? rcu_read_lock_held_common+0xa0/0xa0 [ 65.824154][ T127] ? check_preemption_disabled+0x38/0x220 [ 65.829880][ T127] afs_net_exit+0x1bc/0x310 [ 65.834469][ T127] ? afs_net_init+0xe30/0xe30 [ 65.839158][ T127] ops_exit_list.isra.0+0xa8/0x150 [ 65.844388][ T127] cleanup_net+0x511/0xa50 [ 65.848812][ T127] ? unregister_pernet_device+0x70/0x70 [ 65.854714][ T127] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 65.860702][ T127] process_one_work+0x965/0x1690 [ 65.865834][ T127] ? lock_release+0x800/0x800 [ 65.870517][ T127] ? pwq_dec_nr_in_flight+0x310/0x310 [ 65.876575][ T127] ? rwlock_bug.part.0+0x90/0x90 [ 65.883028][ T127] worker_thread+0x96/0xe10 [ 65.889339][ T127] ? process_one_work+0x1690/0x1690 [ 65.894804][ T127] kthread+0x3b5/0x4a0 [ 65.898878][ T127] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.904604][ T127] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.910416][ T127] ret_from_fork+0x1f/0x30 [ 65.914847][ T127] [ 65.917171][ T127] Allocated by task 6803: [ 65.921497][ T127] save_stack+0x1b/0x40 [ 65.925761][ T127] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 65.931489][ T127] kmem_cache_alloc_trace+0x153/0x7d0 [ 65.936862][ T127] afs_alloc_call+0x55/0x630 [ 65.941457][ T127] afs_charge_preallocation+0xe9/0x2d0 [ 65.947844][ T127] afs_open_socket+0x292/0x360 [ 65.952622][ T127] afs_net_init+0xa6c/0xe30 [ 65.957210][ T127] ops_init+0xaf/0x420 [ 65.961276][ T127] setup_net+0x2de/0x860 [ 65.965535][ T127] copy_net_ns+0x293/0x590 [ 65.970058][ T127] create_new_namespaces+0x3fb/0xb30 [ 65.975622][ T127] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 65.981263][ T127] ksys_unshare+0x43d/0x8e0 [ 65.985960][ T127] __x64_sys_unshare+0x2d/0x40 [ 65.990811][ T127] do_syscall_64+0x60/0xe0 [ 65.995248][ T127] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 66.001129][ T127] [ 66.003460][ T127] Freed by task 127: [ 66.007358][ T127] save_stack+0x1b/0x40 [ 66.011510][ T127] __kasan_slab_free+0xf7/0x140 [ 66.016354][ T127] kfree+0x109/0x2b0 [ 66.020259][ T127] afs_put_call+0x585/0xa40 [ 66.024776][ T127] rxrpc_discard_prealloc+0x764/0xab0 [ 66.030351][ T127] rxrpc_listen+0x147/0x360 [ 66.034892][ T127] afs_close_socket+0x95/0x320 [ 66.039681][ T127] afs_net_exit+0x1bc/0x310 [ 66.044798][ T127] ops_exit_list.isra.0+0xa8/0x150 [ 66.049997][ T127] cleanup_net+0x511/0xa50 [ 66.054411][ T127] process_one_work+0x965/0x1690 [ 66.059365][ T127] worker_thread+0x96/0xe10 [ 66.063866][ T127] kthread+0x3b5/0x4a0 [ 66.068030][ T127] ret_from_fork+0x1f/0x30 [ 66.072439][ T127] [ 66.074768][ T127] The buggy address belongs to the object at ffff8880a62d3000 [ 66.074768][ T127] which belongs to the cache kmalloc-1k of size 1024 [ 66.092481][ T127] The buggy address is located 484 bytes inside of [ 66.092481][ T127] 1024-byte region [ffff8880a62d3000, ffff8880a62d3400) [ 66.107067][ T127] The buggy address belongs to the page: [ 66.112820][ T127] page:ffffea000298b4c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 66.122455][ T127] flags: 0xfffe0000000200(slab) [ 66.127429][ T127] raw: 00fffe0000000200 ffffea0002981808 ffffea00029f8848 ffff8880aa000c40 [ 66.136030][ T127] raw: 0000000000000000 ffff8880a62d3000 0000000100000002 0000000000000000 [ 66.144700][ T127] page dumped because: kasan: bad access detected [ 66.151107][ T127] [ 66.153435][ T127] Memory state around the buggy address: [ 66.159065][ T127] ffff8880a62d3080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 66.167154][ T127] ffff8880a62d3100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 66.175245][ T127] >ffff8880a62d3180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 66.184881][ T127] ^ [ 66.192097][ T127] ffff8880a62d3200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 66.200200][ T127] ffff8880a62d3280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 66.208255][ T127] ================================================================== [ 66.216309][ T127] Disabling lock debugging due to kernel taint [ 66.222505][ T127] Kernel panic - not syncing: panic_on_warn set ... [ 66.229794][ T127] CPU: 0 PID: 127 Comm: kworker/u4:4 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 66.239498][ T127] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 66.249639][ T127] Workqueue: netns cleanup_net [ 66.254394][ T127] Call Trace: [ 66.257709][ T127] dump_stack+0x18f/0x20d [ 66.262144][ T127] ? afs_wake_up_async_call+0x680/0x770 [ 66.267708][ T127] ? afs_put_call+0xa40/0xa40 [ 66.272387][ T127] panic+0x2e3/0x75c [ 66.276306][ T127] ? __warn_printk+0xf3/0xf3 [ 66.280921][ T127] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 66.287695][ T127] ? trace_hardirqs_on+0x55/0x220 [ 66.292729][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 66.298364][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 66.303965][ T127] ? afs_put_call+0xa40/0xa40 [ 66.308674][ T127] end_report+0x4d/0x53 [ 66.312839][ T127] kasan_report.cold+0xd/0x37 [ 66.317614][ T127] ? rcu_read_lock_held_common+0x51/0xa0 [ 66.323287][ T127] ? afs_wake_up_async_call+0x6aa/0x770 [ 66.329278][ T127] afs_wake_up_async_call+0x6aa/0x770 [ 66.334655][ T127] ? afs_close_socket+0x320/0x320 [ 66.339682][ T127] ? afs_put_call+0xa40/0xa40 [ 66.344357][ T127] rxrpc_notify_socket+0x1db/0x5d0 [ 66.350178][ T127] ? afs_put_call+0xa40/0xa40 [ 66.355829][ T127] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 66.362613][ T127] rxrpc_call_completed+0xca/0xf0 [ 66.367821][ T127] rxrpc_discard_prealloc+0x781/0xab0 [ 66.373364][ T127] ? lock_sock_nested+0x94/0x110 [ 66.378666][ T127] rxrpc_listen+0x147/0x360 [ 66.384896][ T127] afs_close_socket+0x95/0x320 [ 66.390546][ T127] ? afs_purge_servers+0x16d/0x300 [ 66.395780][ T127] ? afs_rx_discard_new_call+0x50/0x50 [ 66.401240][ T127] ? init_wait_var_entry+0x200/0x200 [ 66.406538][ T127] ? rcu_read_lock_held_common+0xa0/0xa0 [ 66.412343][ T127] ? check_preemption_disabled+0x38/0x220 [ 66.418060][ T127] afs_net_exit+0x1bc/0x310 [ 66.423070][ T127] ? afs_net_init+0xe30/0xe30 [ 66.428137][ T127] ops_exit_list.isra.0+0xa8/0x150 [ 66.434910][ T127] cleanup_net+0x511/0xa50 [ 66.439424][ T127] ? unregister_pernet_device+0x70/0x70 [ 66.445095][ T127] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 66.452382][ T127] process_one_work+0x965/0x1690 [ 66.457721][ T127] ? lock_release+0x800/0x800 [ 66.463177][ T127] ? pwq_dec_nr_in_flight+0x310/0x310 [ 66.470277][ T127] ? rwlock_bug.part.0+0x90/0x90 [ 66.475323][ T127] worker_thread+0x96/0xe10 [ 66.480062][ T127] ? process_one_work+0x1690/0x1690 [ 66.485351][ T127] kthread+0x3b5/0x4a0 [ 66.489449][ T127] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 66.495182][ T127] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 66.500932][ T127] ret_from_fork+0x1f/0x30 [ 66.506842][ T127] Kernel Offset: disabled [ 66.511167][ T127] Rebooting in 86400 seconds..