[ OK ] Started Getty on tty2. [ OK ] Started Serial Getty on ttyS0. [ OK ] Started Getty on tty1. [ 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 '10.128.10.27' (ECDSA) to the list of known hosts. 2020/07/01 12:09:50 fuzzer started 2020/07/01 12:09:51 connecting to host at 10.128.0.26:45745 2020/07/01 12:09:51 checking machine... 2020/07/01 12:09:51 checking revisions... 2020/07/01 12:09:51 testing simple program... syzkaller login: [ 59.666124][ T6824] IPVS: ftp: loaded support on port[0] = 21 2020/07/01 12:09:51 building call list... [ 60.018152][ T31] tipc: TX() has been purged, node left! [ 60.520406][ T31] ================================================================== [ 60.528643][ T31] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 60.536529][ T31] Write of size 1 at addr ffff8880978c59e4 by task kworker/u4:3/31 [ 60.544405][ T31] [ 60.546736][ T31] CPU: 1 PID: 31 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.555322][ T31] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.566158][ T31] Workqueue: netns cleanup_net [ 60.570911][ T31] Call Trace: [ 60.574201][ T31] dump_stack+0x18f/0x20d [ 60.578534][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.584074][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.589614][ T31] ? afs_put_call+0x440/0x440 [ 60.596027][ T31] print_address_description.constprop.0.cold+0xae/0x436 [ 60.603059][ T31] ? vprintk_func+0x97/0x1a6 [ 60.607666][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.613211][ T31] kasan_report.cold+0x1f/0x37 [ 60.617987][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.623532][ T31] afs_wake_up_async_call+0x430/0x4a0 [ 60.628906][ T31] ? afs_close_socket+0x320/0x320 [ 60.633958][ T31] rxrpc_notify_socket+0x1db/0x5d0 [ 60.639072][ T31] ? afs_put_call+0x440/0x440 [ 60.643877][ T31] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.650292][ T31] rxrpc_call_completed+0xd0/0xf0 [ 60.655317][ T31] rxrpc_discard_prealloc+0x777/0xab0 [ 60.660691][ T31] ? lock_sock_nested+0x94/0x110 [ 60.665737][ T31] rxrpc_listen+0x11c/0x330 [ 60.670242][ T31] afs_close_socket+0x95/0x320 [ 60.675013][ T31] ? afs_purge_servers+0x16d/0x300 [ 60.680126][ T31] ? afs_rx_discard_new_call+0x50/0x50 [ 60.685686][ T31] ? init_wait_var_entry+0x200/0x200 [ 60.690975][ T31] ? check_preemption_disabled+0x38/0x220 [ 60.697349][ T31] afs_net_exit+0x1bc/0x310 [ 60.701849][ T31] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 60.707481][ T31] ops_exit_list+0xb0/0x160 [ 60.711984][ T31] cleanup_net+0x4ea/0xa00 [ 60.716402][ T31] ? __schedule+0x887/0x1eb0 [ 60.720998][ T31] ? ops_free_list.part.0+0x3d0/0x3d0 [ 60.726376][ T31] ? check_preemption_disabled+0x38/0x220 [ 60.732107][ T31] process_one_work+0x94c/0x1670 [ 60.737138][ T31] ? lock_release+0x8d0/0x8d0 [ 60.741814][ T31] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 60.747194][ T31] ? rwlock_bug.part.0+0x90/0x90 [ 60.752149][ T31] worker_thread+0x64c/0x1120 [ 60.756868][ T31] ? __kthread_parkme+0x13f/0x1e0 [ 60.761909][ T31] ? process_one_work+0x1670/0x1670 [ 60.767109][ T31] kthread+0x3b5/0x4a0 [ 60.771272][ T31] ? __kthread_bind_mask+0xc0/0xc0 [ 60.776376][ T31] ? __kthread_bind_mask+0xc0/0xc0 [ 60.781491][ T31] ret_from_fork+0x1f/0x30 [ 60.785913][ T31] [ 60.788583][ T31] Allocated by task 6824: [ 60.792910][ T31] save_stack+0x1b/0x40 [ 60.797061][ T31] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 60.802691][ T31] kmem_cache_alloc_trace+0x14f/0x2d0 [ 60.808057][ T31] afs_alloc_call+0x4f/0x360 [ 60.812665][ T31] afs_charge_preallocation+0xe9/0x2d0 [ 60.818118][ T31] afs_open_socket+0x294/0x360 [ 60.822874][ T31] afs_net_init+0xa6c/0xe30 [ 60.827371][ T31] ops_init+0xaf/0x470 [ 60.831437][ T31] setup_net+0x2d8/0x850 [ 60.835684][ T31] copy_net_ns+0x2cf/0x5e0 [ 60.840124][ T31] create_new_namespaces+0x3f6/0xb10 [ 60.845449][ T31] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 60.851120][ T31] ksys_unshare+0x36c/0x9a0 [ 60.855635][ T31] __x64_sys_unshare+0x2d/0x40 [ 60.860409][ T31] do_syscall_64+0x60/0xe0 [ 60.864825][ T31] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 60.870707][ T31] [ 60.873030][ T31] Freed by task 31: [ 60.876838][ T31] save_stack+0x1b/0x40 [ 60.880991][ T31] __kasan_slab_free+0xf5/0x140 [ 60.886524][ T31] kfree+0x103/0x2c0 [ 60.890408][ T31] afs_put_call+0x345/0x440 [ 60.894918][ T31] rxrpc_discard_prealloc+0x75a/0xab0 [ 60.900290][ T31] rxrpc_listen+0x11c/0x330 [ 60.904777][ T31] afs_close_socket+0x95/0x320 [ 60.909527][ T31] afs_net_exit+0x1bc/0x310 [ 60.914228][ T31] ops_exit_list+0xb0/0x160 [ 60.918730][ T31] cleanup_net+0x4ea/0xa00 [ 60.923140][ T31] process_one_work+0x94c/0x1670 [ 60.928088][ T31] worker_thread+0x64c/0x1120 [ 60.932757][ T31] kthread+0x3b5/0x4a0 [ 60.936820][ T31] ret_from_fork+0x1f/0x30 [ 60.941216][ T31] [ 60.943532][ T31] The buggy address belongs to the object at ffff8880978c5800 [ 60.943532][ T31] which belongs to the cache kmalloc-1k of size 1024 [ 60.957575][ T31] The buggy address is located 484 bytes inside of [ 60.957575][ T31] 1024-byte region [ffff8880978c5800, ffff8880978c5c00) [ 60.970921][ T31] The buggy address belongs to the page: [ 60.976553][ T31] page:ffffea00025e3140 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 60.985787][ T31] flags: 0xfffe0000000200(slab) [ 60.990677][ T31] raw: 00fffe0000000200 ffffea000254f988 ffffea0002a32088 ffff8880aa000c40 [ 61.000095][ T31] raw: 0000000000000000 ffff8880978c5000 0000000100000002 0000000000000000 [ 61.008750][ T31] page dumped because: kasan: bad access detected [ 61.015160][ T31] [ 61.017483][ T31] Memory state around the buggy address: [ 61.023212][ T31] ffff8880978c5880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.031271][ T31] ffff8880978c5900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.039322][ T31] >ffff8880978c5980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.047376][ T31] ^ [ 61.054663][ T31] ffff8880978c5a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.062726][ T31] ffff8880978c5a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.070782][ T31] ================================================================== [ 61.078836][ T31] Disabling lock debugging due to kernel taint [ 61.085054][ T31] Kernel panic - not syncing: panic_on_warn set ... [ 61.091678][ T31] CPU: 1 PID: 31 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.101396][ T31] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.111455][ T31] Workqueue: netns cleanup_net [ 61.116210][ T31] Call Trace: [ 61.119497][ T31] dump_stack+0x18f/0x20d [ 61.123823][ T31] ? afs_wake_up_async_call+0x400/0x4a0 [ 61.129358][ T31] ? afs_put_call+0x440/0x440 [ 61.134032][ T31] panic+0x2e3/0x75c [ 61.137926][ T31] ? __warn_printk+0xf3/0xf3 [ 61.142511][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.148056][ T31] ? trace_hardirqs_on+0x55/0x220 [ 61.153076][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.158611][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.164153][ T31] ? afs_put_call+0x440/0x440 [ 61.168822][ T31] end_report+0x4d/0x53 [ 61.172981][ T31] kasan_report.cold+0xd/0x37 [ 61.177653][ T31] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.183227][ T31] afs_wake_up_async_call+0x430/0x4a0 [ 61.188590][ T31] ? afs_close_socket+0x320/0x320 [ 61.193696][ T31] rxrpc_notify_socket+0x1db/0x5d0 [ 61.198803][ T31] ? afs_put_call+0x440/0x440 [ 61.203476][ T31] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.209885][ T31] rxrpc_call_completed+0xd0/0xf0 [ 61.214906][ T31] rxrpc_discard_prealloc+0x777/0xab0 [ 61.220285][ T31] ? lock_sock_nested+0x94/0x110 [ 61.225219][ T31] rxrpc_listen+0x11c/0x330 [ 61.229727][ T31] afs_close_socket+0x95/0x320 [ 61.234482][ T31] ? afs_purge_servers+0x16d/0x300 [ 61.239586][ T31] ? afs_rx_discard_new_call+0x50/0x50 [ 61.245146][ T31] ? init_wait_var_entry+0x200/0x200 [ 61.250451][ T31] ? check_preemption_disabled+0x38/0x220 [ 61.256167][ T31] afs_net_exit+0x1bc/0x310 [ 61.260679][ T31] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.266354][ T31] ops_exit_list+0xb0/0x160 [ 61.270854][ T31] cleanup_net+0x4ea/0xa00 [ 61.275282][ T31] ? __schedule+0x887/0x1eb0 [ 61.279869][ T31] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.285236][ T31] ? check_preemption_disabled+0x38/0x220 [ 61.290953][ T31] process_one_work+0x94c/0x1670 [ 61.295907][ T31] ? lock_release+0x8d0/0x8d0 [ 61.300584][ T31] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.305949][ T31] ? rwlock_bug.part.0+0x90/0x90 [ 61.310894][ T31] worker_thread+0x64c/0x1120 [ 61.315567][ T31] ? __kthread_parkme+0x13f/0x1e0 [ 61.320609][ T31] ? process_one_work+0x1670/0x1670 [ 61.325797][ T31] kthread+0x3b5/0x4a0 [ 61.329867][ T31] ? __kthread_bind_mask+0xc0/0xc0 [ 61.334970][ T31] ? __kthread_bind_mask+0xc0/0xc0 [ 61.340074][ T31] ret_from_fork+0x1f/0x30 [ 61.345852][ T31] Kernel Offset: disabled [ 61.350183][ T31] Rebooting in 86400 seconds..