[ 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 '10.128.15.192' (ECDSA) to the list of known hosts. 2020/06/19 18:03:17 fuzzer started 2020/06/19 18:03:17 connecting to host at 10.128.0.26:41599 2020/06/19 18:03:17 checking machine... 2020/06/19 18:03:17 checking revisions... 2020/06/19 18:03:17 testing simple program... syzkaller login: [ 56.444489][ T6814] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 18:03:18 building call list... [ 56.760775][ T21] tipc: TX() has been purged, node left! [ 57.252698][ T21] ================================================================== [ 57.260933][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 57.268812][ T21] Write of size 1 at addr ffff8880a02881e4 by task kworker/u4:1/21 [ 57.276680][ T21] [ 57.279021][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 57.287252][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.297297][ T21] Workqueue: netns cleanup_net [ 57.302042][ T21] Call Trace: [ 57.305327][ T21] dump_stack+0x18f/0x20d [ 57.309653][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.315192][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.320728][ T21] ? afs_put_call+0xa40/0xa40 [ 57.325391][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 57.332409][ T21] ? vprintk_func+0x97/0x1a6 [ 57.336999][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.342534][ T21] kasan_report.cold+0x1f/0x37 [ 57.347292][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 57.352906][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.358443][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 57.363810][ T21] ? afs_close_socket+0x320/0x320 [ 57.368825][ T21] ? afs_put_call+0xa40/0xa40 [ 57.373493][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 57.378600][ T21] ? afs_put_call+0xa40/0xa40 [ 57.383273][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 57.389682][ T21] rxrpc_call_completed+0xca/0xf0 [ 57.394706][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 57.400094][ T21] ? lock_sock_nested+0x94/0x110 [ 57.405034][ T21] rxrpc_listen+0x147/0x360 [ 57.409540][ T21] afs_close_socket+0x95/0x320 [ 57.414295][ T21] ? afs_purge_servers+0x16d/0x300 [ 57.419399][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 57.424854][ T21] ? init_wait_var_entry+0x200/0x200 [ 57.430137][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 57.435759][ T21] ? check_preemption_disabled+0x38/0x220 [ 57.441472][ T21] afs_net_exit+0x1bc/0x310 [ 57.445964][ T21] ? afs_net_init+0xe30/0xe30 [ 57.450629][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 57.455733][ T21] cleanup_net+0x511/0xa50 [ 57.460146][ T21] ? unregister_pernet_device+0x70/0x70 [ 57.465693][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 57.471673][ T21] process_one_work+0x965/0x1690 [ 57.476630][ T21] ? lock_release+0x800/0x800 [ 57.481409][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 57.486779][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 57.491717][ T21] worker_thread+0x96/0xe10 [ 57.496218][ T21] ? process_one_work+0x1690/0x1690 [ 57.501410][ T21] kthread+0x3b5/0x4a0 [ 57.505469][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.511178][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 57.516894][ T21] ret_from_fork+0x1f/0x30 [ 57.521316][ T21] [ 57.523647][ T21] Allocated by task 6814: [ 57.527959][ T21] save_stack+0x1b/0x40 [ 57.532121][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 57.537757][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 57.543242][ T21] afs_alloc_call+0x55/0x630 [ 57.547818][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 57.553262][ T21] afs_open_socket+0x292/0x360 [ 57.558010][ T21] afs_net_init+0xa6c/0xe30 [ 57.562504][ T21] ops_init+0xaf/0x420 [ 57.566580][ T21] setup_net+0x2de/0x860 [ 57.570823][ T21] copy_net_ns+0x293/0x590 [ 57.575235][ T21] create_new_namespaces+0x3fb/0xb30 [ 57.580516][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 57.586145][ T21] ksys_unshare+0x43d/0x8e0 [ 57.590649][ T21] __x64_sys_unshare+0x2d/0x40 [ 57.595528][ T21] do_syscall_64+0x60/0xe0 [ 57.599937][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 57.605916][ T21] [ 57.608280][ T21] Freed by task 21: [ 57.612096][ T21] save_stack+0x1b/0x40 [ 57.616250][ T21] __kasan_slab_free+0xf7/0x140 [ 57.621084][ T21] kfree+0x109/0x2b0 [ 57.624965][ T21] afs_put_call+0x585/0xa40 [ 57.629467][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 57.634828][ T21] rxrpc_listen+0x147/0x360 [ 57.639314][ T21] afs_close_socket+0x95/0x320 [ 57.644062][ T21] afs_net_exit+0x1bc/0x310 [ 57.648558][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 57.653675][ T21] cleanup_net+0x511/0xa50 [ 57.658200][ T21] process_one_work+0x965/0x1690 [ 57.663124][ T21] worker_thread+0x96/0xe10 [ 57.667615][ T21] kthread+0x3b5/0x4a0 [ 57.671663][ T21] ret_from_fork+0x1f/0x30 [ 57.676046][ T21] [ 57.678356][ T21] The buggy address belongs to the object at ffff8880a0288000 [ 57.678356][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 57.692503][ T21] The buggy address is located 484 bytes inside of [ 57.692503][ T21] 1024-byte region [ffff8880a0288000, ffff8880a0288400) [ 57.705840][ T21] The buggy address belongs to the page: [ 57.711483][ T21] page:ffffea000280a200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 57.720587][ T21] flags: 0xfffe0000000200(slab) [ 57.725543][ T21] raw: 00fffe0000000200 ffffea00027a6988 ffffea00027be948 ffff8880aa000c40 [ 57.734116][ T21] raw: 0000000000000000 ffff8880a0288000 0000000100000002 0000000000000000 [ 57.742719][ T21] page dumped because: kasan: bad access detected [ 57.749113][ T21] [ 57.751425][ T21] Memory state around the buggy address: [ 57.757044][ T21] ffff8880a0288080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.765099][ T21] ffff8880a0288100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.773162][ T21] >ffff8880a0288180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.781727][ T21] ^ [ 57.789024][ T21] ffff8880a0288200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.797078][ T21] ffff8880a0288280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 57.805127][ T21] ================================================================== [ 57.813414][ T21] Disabling lock debugging due to kernel taint [ 57.819588][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 57.826179][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 57.835784][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 57.845852][ T21] Workqueue: netns cleanup_net [ 57.850615][ T21] Call Trace: [ 57.853894][ T21] dump_stack+0x18f/0x20d [ 57.858210][ T21] ? afs_wake_up_async_call+0x670/0x770 [ 57.863748][ T21] ? afs_put_call+0xa40/0xa40 [ 57.868416][ T21] panic+0x2e3/0x75c [ 57.872305][ T21] ? __warn_printk+0xf3/0xf3 [ 57.876888][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 57.883031][ T21] ? trace_hardirqs_on+0x55/0x220 [ 57.888041][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.893576][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.899105][ T21] ? afs_put_call+0xa40/0xa40 [ 57.903764][ T21] end_report+0x4d/0x53 [ 57.907908][ T21] kasan_report.cold+0xd/0x37 [ 57.912574][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 57.918194][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 57.923725][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 57.929083][ T21] ? afs_close_socket+0x320/0x320 [ 57.934098][ T21] ? afs_put_call+0xa40/0xa40 [ 57.938764][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 57.943886][ T21] ? afs_put_call+0xa40/0xa40 [ 57.948554][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 57.954958][ T21] rxrpc_call_completed+0xca/0xf0 [ 57.959973][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 57.965338][ T21] ? lock_sock_nested+0x94/0x110 [ 57.970296][ T21] rxrpc_listen+0x147/0x360 [ 57.974813][ T21] afs_close_socket+0x95/0x320 [ 57.979563][ T21] ? afs_purge_servers+0x16d/0x300 [ 57.984662][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 57.990112][ T21] ? init_wait_var_entry+0x200/0x200 [ 57.995390][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 58.001014][ T21] ? check_preemption_disabled+0x38/0x220 [ 58.006720][ T21] afs_net_exit+0x1bc/0x310 [ 58.011208][ T21] ? afs_net_init+0xe30/0xe30 [ 58.015903][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 58.021004][ T21] cleanup_net+0x511/0xa50 [ 58.025405][ T21] ? unregister_pernet_device+0x70/0x70 [ 58.030941][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 58.036910][ T21] process_one_work+0x965/0x1690 [ 58.041838][ T21] ? lock_release+0x800/0x800 [ 58.046502][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 58.051860][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 58.056917][ T21] worker_thread+0x96/0xe10 [ 58.061409][ T21] ? process_one_work+0x1690/0x1690 [ 58.066591][ T21] kthread+0x3b5/0x4a0 [ 58.070649][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 58.076351][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 58.082054][ T21] ret_from_fork+0x1f/0x30 [ 58.087644][ T21] Kernel Offset: disabled [ 58.091975][ T21] Rebooting in 86400 seconds..