[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty2. [ OK ] Started Getty on tty1. [ OK ] Started Serial Getty on ttyS0. [ 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. Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.26' (ECDSA) to the list of known hosts. 2020/06/16 07:13:43 fuzzer started 2020/06/16 07:13:43 connecting to host at 10.128.0.26:44577 2020/06/16 07:13:43 checking machine... 2020/06/16 07:13:43 checking revisions... 2020/06/16 07:13:43 testing simple program... syzkaller login: [ 60.822883][ T6855] IPVS: ftp: loaded support on port[0] = 21 2020/06/16 07:13:44 building call list... [ 61.184123][ T7] tipc: TX() has been purged, node left! [ 61.716329][ T7] ================================================================== [ 61.724567][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.732450][ T7] Write of size 1 at addr ffff8880a966e9e4 by task kworker/u4:0/7 [ 61.740233][ T7] [ 61.742559][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-next-20200616-syzkaller #0 [ 61.751912][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.761973][ T7] Workqueue: netns cleanup_net [ 61.766726][ T7] Call Trace: [ 61.770018][ T7] dump_stack+0x18f/0x20d [ 61.774349][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.779907][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.785447][ T7] ? afs_put_call+0xa40/0xa40 [ 61.790124][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.797235][ T7] ? vprintk_func+0x97/0x1a6 [ 61.801826][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.807364][ T7] kasan_report.cold+0x1f/0x37 [ 61.812129][ T7] ? rcu_read_lock_held_common+0x71/0xa0 [ 61.817753][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.823317][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 61.828685][ T7] ? afs_close_socket+0x320/0x320 [ 61.833718][ T7] ? afs_put_call+0xa40/0xa40 [ 61.838393][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 61.843505][ T7] ? afs_put_call+0xa40/0xa40 [ 61.848191][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.854615][ T7] rxrpc_call_completed+0xca/0xf0 [ 61.859671][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 61.865045][ T7] ? lock_sock_nested+0x94/0x110 [ 61.869983][ T7] rxrpc_listen+0x147/0x360 [ 61.874486][ T7] afs_close_socket+0x95/0x320 [ 61.879245][ T7] ? afs_purge_servers+0x16d/0x300 [ 61.884360][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 61.889840][ T7] ? init_wait_var_entry+0x200/0x200 [ 61.895128][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.900755][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.906494][ T7] afs_net_exit+0x1bc/0x310 [ 61.910999][ T7] ? afs_net_init+0xe30/0xe30 [ 61.915694][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 61.920807][ T7] cleanup_net+0x511/0xa50 [ 61.925226][ T7] ? unregister_pernet_device+0x70/0x70 [ 61.930810][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.936802][ T7] process_one_work+0x965/0x1690 [ 61.941946][ T7] ? lock_release+0x800/0x800 [ 61.946632][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.952013][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 61.956969][ T7] worker_thread+0x96/0xe10 [ 61.961523][ T7] ? process_one_work+0x1690/0x1690 [ 61.966722][ T7] kthread+0x3b5/0x4a0 [ 61.970790][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.976667][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.982413][ T7] ret_from_fork+0x1f/0x30 [ 61.986841][ T7] [ 61.989181][ T7] Allocated by task 6855: [ 61.993507][ T7] save_stack+0x1b/0x40 [ 61.997662][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.003289][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.008659][ T7] afs_alloc_call+0x55/0x630 [ 62.013243][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 62.018696][ T7] afs_open_socket+0x292/0x360 [ 62.023608][ T7] afs_net_init+0xa6c/0xe30 [ 62.028216][ T7] ops_init+0xaf/0x420 [ 62.032543][ T7] setup_net+0x2de/0x860 [ 62.036792][ T7] copy_net_ns+0x293/0x590 [ 62.041204][ T7] create_new_namespaces+0x3fb/0xb30 [ 62.046483][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.052236][ T7] ksys_unshare+0x43d/0x8e0 [ 62.056733][ T7] __x64_sys_unshare+0x2d/0x40 [ 62.061502][ T7] do_syscall_64+0x60/0xe0 [ 62.065937][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.071831][ T7] [ 62.074168][ T7] Freed by task 7: [ 62.077951][ T7] save_stack+0x1b/0x40 [ 62.082121][ T7] __kasan_slab_free+0xf7/0x140 [ 62.087097][ T7] kfree+0x109/0x2b0 [ 62.091009][ T7] afs_put_call+0x585/0xa40 [ 62.095506][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 62.100870][ T7] rxrpc_listen+0x147/0x360 [ 62.105387][ T7] afs_close_socket+0x95/0x320 [ 62.110165][ T7] afs_net_exit+0x1bc/0x310 [ 62.114662][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.119767][ T7] cleanup_net+0x511/0xa50 [ 62.124179][ T7] process_one_work+0x965/0x1690 [ 62.129109][ T7] worker_thread+0x96/0xe10 [ 62.133611][ T7] kthread+0x3b5/0x4a0 [ 62.137673][ T7] ret_from_fork+0x1f/0x30 [ 62.142079][ T7] [ 62.144401][ T7] The buggy address belongs to the object at ffff8880a966e800 [ 62.144401][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 62.158987][ T7] The buggy address is located 484 bytes inside of [ 62.158987][ T7] 1024-byte region [ffff8880a966e800, ffff8880a966ec00) [ 62.172419][ T7] The buggy address belongs to the page: [ 62.178048][ T7] page:ffffea0002a59b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.187147][ T7] flags: 0xfffe0000000200(slab) [ 62.192107][ T7] raw: 00fffe0000000200 ffffea00025ee088 ffffea000280a408 ffff8880aa000c40 [ 62.200694][ T7] raw: 0000000000000000 ffff8880a966e000 0000000100000002 0000000000000000 [ 62.209264][ T7] page dumped because: kasan: bad access detected [ 62.215665][ T7] [ 62.217979][ T7] Memory state around the buggy address: [ 62.223602][ T7] ffff8880a966e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.231656][ T7] ffff8880a966e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.239711][ T7] >ffff8880a966e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.248715][ T7] ^ [ 62.255920][ T7] ffff8880a966ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.264512][ T7] ffff8880a966ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.272563][ T7] ================================================================== [ 62.280697][ T7] Disabling lock debugging due to kernel taint [ 62.286908][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 62.293511][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-next-20200616-syzkaller #0 [ 62.304364][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.314425][ T7] Workqueue: netns cleanup_net [ 62.319191][ T7] Call Trace: [ 62.322471][ T7] dump_stack+0x18f/0x20d [ 62.326801][ T7] ? afs_wake_up_async_call+0x600/0x770 [ 62.332350][ T7] ? afs_put_call+0xa40/0xa40 [ 62.337030][ T7] panic+0x2e3/0x75c [ 62.340958][ T7] ? __warn_printk+0xf3/0xf3 [ 62.345579][ T7] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.351855][ T7] ? trace_hardirqs_on+0x55/0x220 [ 62.356879][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.362432][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.367964][ T7] ? afs_put_call+0xa40/0xa40 [ 62.372632][ T7] end_report+0x4d/0x53 [ 62.376779][ T7] kasan_report.cold+0xd/0x37 [ 62.381434][ T7] ? rcu_read_lock_held_common+0x71/0xa0 [ 62.387052][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.392589][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 62.397947][ T7] ? afs_close_socket+0x320/0x320 [ 62.402945][ T7] ? afs_put_call+0xa40/0xa40 [ 62.407612][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 62.412710][ T7] ? afs_put_call+0xa40/0xa40 [ 62.417371][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.423798][ T7] rxrpc_call_completed+0xca/0xf0 [ 62.428815][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 62.434247][ T7] ? lock_sock_nested+0x94/0x110 [ 62.439189][ T7] rxrpc_listen+0x147/0x360 [ 62.443693][ T7] afs_close_socket+0x95/0x320 [ 62.448443][ T7] ? afs_purge_servers+0x16d/0x300 [ 62.453571][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 62.459373][ T7] ? init_wait_var_entry+0x200/0x200 [ 62.464645][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.470260][ T7] ? check_preemption_disabled+0x38/0x220 [ 62.475973][ T7] afs_net_exit+0x1bc/0x310 [ 62.480583][ T7] ? afs_net_init+0xe30/0xe30 [ 62.485258][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 62.490354][ T7] cleanup_net+0x511/0xa50 [ 62.494781][ T7] ? unregister_pernet_device+0x70/0x70 [ 62.500318][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.506301][ T7] process_one_work+0x965/0x1690 [ 62.511248][ T7] ? lock_release+0x800/0x800 [ 62.515921][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.521288][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 62.526303][ T7] worker_thread+0x96/0xe10 [ 62.530799][ T7] ? process_one_work+0x1690/0x1690 [ 62.535982][ T7] kthread+0x3b5/0x4a0 [ 62.540095][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.545804][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.551540][ T7] ret_from_fork+0x1f/0x30 [ 62.557428][ T7] Kernel Offset: disabled [ 62.561907][ T7] Rebooting in 86400 seconds..