[ 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 '10.128.10.53' (ECDSA) to the list of known hosts. 2020/06/25 15:06:41 fuzzer started 2020/06/25 15:06:41 connecting to host at 10.128.0.26:39311 2020/06/25 15:06:41 checking machine... 2020/06/25 15:06:41 checking revisions... 2020/06/25 15:06:41 testing simple program... syzkaller login: [ 60.061506][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 15:06:42 building call list... [ 60.387563][ T126] tipc: TX() has been purged, node left! [ 60.889545][ T126] ================================================================== [ 60.897797][ T126] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 60.905680][ T126] Write of size 1 at addr ffff8880a8ffb9e4 by task kworker/u4:3/126 [ 60.913647][ T126] [ 60.916063][ T126] CPU: 1 PID: 126 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.924461][ T126] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.934517][ T126] Workqueue: netns cleanup_net [ 60.939270][ T126] Call Trace: [ 60.942559][ T126] dump_stack+0x18f/0x20d [ 60.946889][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.952697][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.958238][ T126] ? afs_put_call+0x440/0x440 [ 60.962939][ T126] print_address_description.constprop.0.cold+0xae/0x436 [ 60.969966][ T126] ? vprintk_func+0x97/0x1a6 [ 60.974569][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.980197][ T126] kasan_report.cold+0x1f/0x37 [ 60.984975][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.990520][ T126] afs_wake_up_async_call+0x430/0x4a0 [ 60.995885][ T126] ? afs_close_socket+0x320/0x320 [ 61.001002][ T126] rxrpc_notify_socket+0x1db/0x5d0 [ 61.006117][ T126] ? afs_put_call+0x440/0x440 [ 61.010794][ T126] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.017206][ T126] rxrpc_call_completed+0xd0/0xf0 [ 61.022231][ T126] rxrpc_discard_prealloc+0x777/0xab0 [ 61.027603][ T126] ? lock_sock_nested+0x94/0x110 [ 61.032539][ T126] rxrpc_listen+0x11c/0x330 [ 61.037130][ T126] afs_close_socket+0x95/0x320 [ 61.041891][ T126] ? afs_purge_servers+0x16d/0x300 [ 61.046999][ T126] ? afs_rx_discard_new_call+0x50/0x50 [ 61.052460][ T126] ? init_wait_var_entry+0x200/0x200 [ 61.057751][ T126] ? check_preemption_disabled+0x38/0x220 [ 61.063469][ T126] afs_net_exit+0x1bc/0x310 [ 61.067967][ T126] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.073593][ T126] ops_exit_list+0xb0/0x160 [ 61.078097][ T126] cleanup_net+0x4ea/0xa00 [ 61.082552][ T126] ? __schedule+0x887/0x1eb0 [ 61.087139][ T126] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.092522][ T126] ? check_preemption_disabled+0x38/0x220 [ 61.098253][ T126] process_one_work+0x94c/0x1670 [ 61.103376][ T126] ? lock_release+0x8d0/0x8d0 [ 61.108050][ T126] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.113423][ T126] ? rwlock_bug.part.0+0x90/0x90 [ 61.118487][ T126] worker_thread+0x64c/0x1120 [ 61.123171][ T126] ? __kthread_parkme+0x13f/0x1e0 [ 61.128539][ T126] ? process_one_work+0x1670/0x1670 [ 61.133741][ T126] kthread+0x3b5/0x4a0 [ 61.137803][ T126] ? __kthread_bind_mask+0xc0/0xc0 [ 61.142906][ T126] ? __kthread_bind_mask+0xc0/0xc0 [ 61.148016][ T126] ret_from_fork+0x1f/0x30 [ 61.152437][ T126] [ 61.154767][ T126] Allocated by task 6820: [ 61.159091][ T126] save_stack+0x1b/0x40 [ 61.163248][ T126] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 61.169132][ T126] kmem_cache_alloc_trace+0x14f/0x2d0 [ 61.174518][ T126] afs_alloc_call+0x4f/0x360 [ 61.179109][ T126] afs_charge_preallocation+0xe9/0x2d0 [ 61.184560][ T126] afs_open_socket+0x294/0x360 [ 61.189318][ T126] afs_net_init+0xa6c/0xe30 [ 61.193812][ T126] ops_init+0xaf/0x470 [ 61.197876][ T126] setup_net+0x2d8/0x850 [ 61.202111][ T126] copy_net_ns+0x2cf/0x5e0 [ 61.206520][ T126] create_new_namespaces+0x3f6/0xb10 [ 61.211806][ T126] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.217429][ T126] ksys_unshare+0x36c/0x9a0 [ 61.221923][ T126] __x64_sys_unshare+0x2d/0x40 [ 61.226677][ T126] do_syscall_64+0x60/0xe0 [ 61.231089][ T126] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.236966][ T126] [ 61.239288][ T126] Freed by task 126: [ 61.243178][ T126] save_stack+0x1b/0x40 [ 61.247340][ T126] __kasan_slab_free+0xf5/0x140 [ 61.252183][ T126] kfree+0x103/0x2c0 [ 61.256072][ T126] afs_put_call+0x345/0x440 [ 61.260571][ T126] rxrpc_discard_prealloc+0x75a/0xab0 [ 61.265937][ T126] rxrpc_listen+0x11c/0x330 [ 61.270432][ T126] afs_close_socket+0x95/0x320 [ 61.275188][ T126] afs_net_exit+0x1bc/0x310 [ 61.279702][ T126] ops_exit_list+0xb0/0x160 [ 61.284200][ T126] cleanup_net+0x4ea/0xa00 [ 61.288620][ T126] process_one_work+0x94c/0x1670 [ 61.293556][ T126] worker_thread+0x64c/0x1120 [ 61.298229][ T126] kthread+0x3b5/0x4a0 [ 61.302303][ T126] ret_from_fork+0x1f/0x30 [ 61.306705][ T126] [ 61.309034][ T126] The buggy address belongs to the object at ffff8880a8ffb800 [ 61.309034][ T126] which belongs to the cache kmalloc-1k of size 1024 [ 61.324381][ T126] The buggy address is located 484 bytes inside of [ 61.324381][ T126] 1024-byte region [ffff8880a8ffb800, ffff8880a8ffbc00) [ 61.337726][ T126] The buggy address belongs to the page: [ 61.343354][ T126] page:ffffea0002a3fec0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.352453][ T126] flags: 0xfffe0000000200(slab) [ 61.357305][ T126] raw: 00fffe0000000200 ffffea00028a94c8 ffffea00025f8c88 ffff8880aa000c40 [ 61.365897][ T126] raw: 0000000000000000 ffff8880a8ffb000 0000000100000002 0000000000000000 [ 61.374466][ T126] page dumped because: kasan: bad access detected [ 61.381038][ T126] [ 61.383357][ T126] Memory state around the buggy address: [ 61.388980][ T126] ffff8880a8ffb880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.397648][ T126] ffff8880a8ffb900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.405701][ T126] >ffff8880a8ffb980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.413749][ T126] ^ [ 61.421064][ T126] ffff8880a8ffba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.429134][ T126] ffff8880a8ffba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.437196][ T126] ================================================================== [ 61.445492][ T126] Disabling lock debugging due to kernel taint [ 61.451718][ T126] Kernel panic - not syncing: panic_on_warn set ... [ 61.458314][ T126] CPU: 1 PID: 126 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.468186][ T126] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.478252][ T126] Workqueue: netns cleanup_net [ 61.483014][ T126] Call Trace: [ 61.486289][ T126] dump_stack+0x18f/0x20d [ 61.490716][ T126] ? afs_wake_up_async_call+0x3d0/0x4a0 [ 61.496300][ T126] ? afs_put_call+0x440/0x440 [ 61.501011][ T126] panic+0x2e3/0x75c [ 61.504919][ T126] ? __warn_printk+0xf3/0xf3 [ 61.509500][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.515107][ T126] ? trace_hardirqs_on+0x55/0x220 [ 61.520115][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.525721][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.531253][ T126] ? afs_put_call+0x440/0x440 [ 61.535904][ T126] end_report+0x4d/0x53 [ 61.540033][ T126] kasan_report.cold+0xd/0x37 [ 61.544701][ T126] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.550258][ T126] afs_wake_up_async_call+0x430/0x4a0 [ 61.555630][ T126] ? afs_close_socket+0x320/0x320 [ 61.560667][ T126] rxrpc_notify_socket+0x1db/0x5d0 [ 61.565781][ T126] ? afs_put_call+0x440/0x440 [ 61.570476][ T126] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.576897][ T126] rxrpc_call_completed+0xd0/0xf0 [ 61.581919][ T126] rxrpc_discard_prealloc+0x777/0xab0 [ 61.587372][ T126] ? lock_sock_nested+0x94/0x110 [ 61.592302][ T126] rxrpc_listen+0x11c/0x330 [ 61.596795][ T126] afs_close_socket+0x95/0x320 [ 61.601547][ T126] ? afs_purge_servers+0x16d/0x300 [ 61.606649][ T126] ? afs_rx_discard_new_call+0x50/0x50 [ 61.612362][ T126] ? init_wait_var_entry+0x200/0x200 [ 61.617640][ T126] ? check_preemption_disabled+0x38/0x220 [ 61.623348][ T126] afs_net_exit+0x1bc/0x310 [ 61.627843][ T126] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.633462][ T126] ops_exit_list+0xb0/0x160 [ 61.637959][ T126] cleanup_net+0x4ea/0xa00 [ 61.642365][ T126] ? __schedule+0x887/0x1eb0 [ 61.647031][ T126] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.652391][ T126] ? check_preemption_disabled+0x38/0x220 [ 61.658104][ T126] process_one_work+0x94c/0x1670 [ 61.663036][ T126] ? lock_release+0x8d0/0x8d0 [ 61.667706][ T126] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.673075][ T126] ? rwlock_bug.part.0+0x90/0x90 [ 61.678013][ T126] worker_thread+0x64c/0x1120 [ 61.682687][ T126] ? __kthread_parkme+0x13f/0x1e0 [ 61.687709][ T126] ? process_one_work+0x1670/0x1670 [ 61.692898][ T126] kthread+0x3b5/0x4a0 [ 61.696954][ T126] ? __kthread_bind_mask+0xc0/0xc0 [ 61.702052][ T126] ? __kthread_bind_mask+0xc0/0xc0 [ 61.707158][ T126] ret_from_fork+0x1f/0x30 [ 61.713110][ T126] Kernel Offset: disabled [ 61.717438][ T126] Rebooting in 86400 seconds..