[ 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 '10.128.10.60' (ECDSA) to the list of known hosts. 2020/06/25 14:57:56 fuzzer started 2020/06/25 14:57:57 connecting to host at 10.128.0.26:45009 2020/06/25 14:57:57 checking machine... 2020/06/25 14:57:57 checking revisions... 2020/06/25 14:57:57 testing simple program... syzkaller login: [ 60.061500][ T6829] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 14:57:57 building call list... [ 60.438900][ T7] tipc: TX() has been purged, node left! [ 60.951095][ T7] ================================================================== [ 60.959328][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 60.967225][ T7] Write of size 1 at addr ffff8880a19861e4 by task kworker/u4:0/7 [ 60.975017][ T7] [ 60.977397][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.985537][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.995595][ T7] Workqueue: netns cleanup_net [ 61.000363][ T7] Call Trace: [ 61.003914][ T7] dump_stack+0x18f/0x20d [ 61.008242][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.013797][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.019340][ T7] ? afs_put_call+0x440/0x440 [ 61.024014][ T7] print_address_description.constprop.0.cold+0xae/0x436 [ 61.031058][ T7] ? vprintk_func+0x97/0x1a6 [ 61.035651][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.041191][ T7] kasan_report.cold+0x1f/0x37 [ 61.045956][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.051500][ T7] afs_wake_up_async_call+0x430/0x4a0 [ 61.056867][ T7] ? afs_close_socket+0x320/0x320 [ 61.061892][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 61.067009][ T7] ? afs_put_call+0x440/0x440 [ 61.071682][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.078102][ T7] rxrpc_call_completed+0xd0/0xf0 [ 61.083218][ T7] rxrpc_discard_prealloc+0x777/0xab0 [ 61.088586][ T7] ? lock_sock_nested+0x94/0x110 [ 61.093620][ T7] rxrpc_listen+0x11c/0x330 [ 61.098124][ T7] afs_close_socket+0x95/0x320 [ 61.102891][ T7] ? afs_purge_servers+0x16d/0x300 [ 61.107999][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 61.114067][ T7] ? init_wait_var_entry+0x200/0x200 [ 61.119368][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.125090][ T7] afs_net_exit+0x1bc/0x310 [ 61.129689][ T7] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.135323][ T7] ops_exit_list+0xb0/0x160 [ 61.139827][ T7] cleanup_net+0x4ea/0xa00 [ 61.144328][ T7] ? __schedule+0x887/0x1eb0 [ 61.148915][ T7] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.154288][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.160018][ T7] process_one_work+0x94c/0x1670 [ 61.164973][ T7] ? lock_release+0x8d0/0x8d0 [ 61.169651][ T7] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.175112][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 61.180060][ T7] worker_thread+0x64c/0x1120 [ 61.184753][ T7] ? process_one_work+0x1670/0x1670 [ 61.189958][ T7] kthread+0x3b5/0x4a0 [ 61.194295][ T7] ? __kthread_bind_mask+0xc0/0xc0 [ 61.199411][ T7] ? __kthread_bind_mask+0xc0/0xc0 [ 61.204531][ T7] ret_from_fork+0x1f/0x30 [ 61.209050][ T7] [ 61.211372][ T7] Allocated by task 6829: [ 61.215698][ T7] save_stack+0x1b/0x40 [ 61.219935][ T7] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 61.225562][ T7] kmem_cache_alloc_trace+0x14f/0x2d0 [ 61.231016][ T7] afs_alloc_call+0x4f/0x360 [ 61.235604][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 61.241055][ T7] afs_open_socket+0x294/0x360 [ 61.245809][ T7] afs_net_init+0xa6c/0xe30 [ 61.250339][ T7] ops_init+0xaf/0x470 [ 61.254400][ T7] setup_net+0x2d8/0x850 [ 61.258634][ T7] copy_net_ns+0x2cf/0x5e0 [ 61.263047][ T7] create_new_namespaces+0x3f6/0xb10 [ 61.269029][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.274654][ T7] ksys_unshare+0x36c/0x9a0 [ 61.279967][ T7] __x64_sys_unshare+0x2d/0x40 [ 61.284740][ T7] do_syscall_64+0x60/0xe0 [ 61.289174][ T7] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.295267][ T7] [ 61.297603][ T7] Freed by task 7: [ 61.304307][ T7] save_stack+0x1b/0x40 [ 61.308581][ T7] __kasan_slab_free+0xf5/0x140 [ 61.313437][ T7] kfree+0x103/0x2c0 [ 61.317586][ T7] afs_put_call+0x345/0x440 [ 61.322093][ T7] rxrpc_discard_prealloc+0x75a/0xab0 [ 61.327475][ T7] rxrpc_listen+0x11c/0x330 [ 61.331971][ T7] afs_close_socket+0x95/0x320 [ 61.336729][ T7] afs_net_exit+0x1bc/0x310 [ 61.341235][ T7] ops_exit_list+0xb0/0x160 [ 61.345818][ T7] cleanup_net+0x4ea/0xa00 [ 61.350456][ T7] process_one_work+0x94c/0x1670 [ 61.355386][ T7] worker_thread+0x64c/0x1120 [ 61.360060][ T7] kthread+0x3b5/0x4a0 [ 61.364136][ T7] ret_from_fork+0x1f/0x30 [ 61.369927][ T7] [ 61.372250][ T7] The buggy address belongs to the object at ffff8880a1986000 [ 61.372250][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 61.386569][ T7] The buggy address is located 484 bytes inside of [ 61.386569][ T7] 1024-byte region [ffff8880a1986000, ffff8880a1986400) [ 61.399912][ T7] The buggy address belongs to the page: [ 61.405541][ T7] page:ffffea0002866180 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.414648][ T7] flags: 0xfffe0000000200(slab) [ 61.419504][ T7] raw: 00fffe0000000200 ffffea0002790b08 ffffea00028edf88 ffff8880aa000c40 [ 61.428083][ T7] raw: 0000000000000000 ffff8880a1986000 0000000100000002 0000000000000000 [ 61.436743][ T7] page dumped because: kasan: bad access detected [ 61.443140][ T7] [ 61.445466][ T7] Memory state around the buggy address: [ 61.451093][ T7] ffff8880a1986080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.459155][ T7] ffff8880a1986100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.467210][ T7] >ffff8880a1986180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.475262][ T7] ^ [ 61.482469][ T7] ffff8880a1986200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.490525][ T7] ffff8880a1986280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.498594][ T7] ================================================================== [ 61.506643][ T7] Disabling lock debugging due to kernel taint [ 61.512854][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 61.519456][ T7] CPU: 1 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.528988][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.539051][ T7] Workqueue: netns cleanup_net [ 61.543800][ T7] Call Trace: [ 61.547081][ T7] dump_stack+0x18f/0x20d [ 61.551456][ T7] ? afs_wake_up_async_call+0x370/0x4a0 [ 61.557015][ T7] ? afs_put_call+0x440/0x440 [ 61.561698][ T7] panic+0x2e3/0x75c [ 61.565594][ T7] ? __warn_printk+0xf3/0xf3 [ 61.570194][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.575750][ T7] ? trace_hardirqs_on+0x55/0x220 [ 61.580783][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.586324][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.592554][ T7] ? afs_put_call+0x440/0x440 [ 61.597230][ T7] end_report+0x4d/0x53 [ 61.601381][ T7] kasan_report.cold+0xd/0x37 [ 61.606052][ T7] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.611591][ T7] afs_wake_up_async_call+0x430/0x4a0 [ 61.618062][ T7] ? afs_close_socket+0x320/0x320 [ 61.623212][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 61.628322][ T7] ? afs_put_call+0x440/0x440 [ 61.633320][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.640894][ T7] rxrpc_call_completed+0xd0/0xf0 [ 61.646087][ T7] rxrpc_discard_prealloc+0x777/0xab0 [ 61.651813][ T7] ? lock_sock_nested+0x94/0x110 [ 61.656835][ T7] rxrpc_listen+0x11c/0x330 [ 61.661854][ T7] afs_close_socket+0x95/0x320 [ 61.666788][ T7] ? afs_purge_servers+0x16d/0x300 [ 61.671979][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 61.678474][ T7] ? init_wait_var_entry+0x200/0x200 [ 61.684628][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.690906][ T7] afs_net_exit+0x1bc/0x310 [ 61.695668][ T7] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.702162][ T7] ops_exit_list+0xb0/0x160 [ 61.706768][ T7] cleanup_net+0x4ea/0xa00 [ 61.711628][ T7] ? __schedule+0x887/0x1eb0 [ 61.716390][ T7] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.722296][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.728121][ T7] process_one_work+0x94c/0x1670 [ 61.733143][ T7] ? lock_release+0x8d0/0x8d0 [ 61.737821][ T7] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.743186][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 61.748128][ T7] worker_thread+0x64c/0x1120 [ 61.752808][ T7] ? process_one_work+0x1670/0x1670 [ 61.757995][ T7] kthread+0x3b5/0x4a0 [ 61.762069][ T7] ? __kthread_bind_mask+0xc0/0xc0 [ 61.767177][ T7] ? __kthread_bind_mask+0xc0/0xc0 [ 61.772292][ T7] ret_from_fork+0x1f/0x30 [ 61.778402][ T7] Kernel Offset: disabled [ 61.782721][ T7] Rebooting in 86400 seconds..