[ 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 '10.128.1.13' (ECDSA) to the list of known hosts. 2020/06/25 16:28:36 fuzzer started 2020/06/25 16:28:37 connecting to host at 10.128.0.26:45095 2020/06/25 16:28:37 checking machine... 2020/06/25 16:28:37 checking revisions... 2020/06/25 16:28:37 testing simple program... syzkaller login: [ 61.198164][ T6878] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 16:28:37 building call list... [ 61.557774][ T21] tipc: TX() has been purged, node left! [ 62.070282][ T21] ================================================================== [ 62.078623][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 62.086957][ T21] Write of size 1 at addr ffff8880a794f9e4 by task kworker/u4:1/21 [ 62.095054][ T21] [ 62.098009][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc2-syzkaller #0 [ 62.107279][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.120115][ T21] Workqueue: netns cleanup_net [ 62.125912][ T21] Call Trace: [ 62.129293][ T21] dump_stack+0x18f/0x20d [ 62.134301][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.140777][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.146699][ T21] ? afs_put_call+0x440/0x440 [ 62.151462][ T21] print_address_description.constprop.0.cold+0xae/0x436 [ 62.158676][ T21] ? vprintk_func+0x97/0x1a6 [ 62.163539][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.169517][ T21] kasan_report.cold+0x1f/0x37 [ 62.174455][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.180176][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 62.185555][ T21] ? afs_close_socket+0x320/0x320 [ 62.190977][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.197961][ T21] ? afs_put_call+0x440/0x440 [ 62.204596][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.211626][ T21] rxrpc_call_completed+0xd0/0xf0 [ 62.217583][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 62.227253][ T21] ? lock_sock_nested+0x94/0x110 [ 62.232567][ T21] rxrpc_listen+0x11c/0x330 [ 62.237154][ T21] afs_close_socket+0x95/0x320 [ 62.242029][ T21] ? afs_purge_servers+0x181/0x330 [ 62.247594][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.254085][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.259410][ T21] afs_net_exit+0x1c4/0x310 [ 62.263997][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 62.269660][ T21] ops_exit_list+0xb0/0x160 [ 62.274197][ T21] cleanup_net+0x4ea/0xa00 [ 62.278716][ T21] ? __schedule+0x887/0x1eb0 [ 62.283391][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 62.289308][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.295122][ T21] process_one_work+0x94c/0x1670 [ 62.300391][ T21] ? lock_release+0x8d0/0x8d0 [ 62.309451][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 62.315612][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.321166][ T21] worker_thread+0x64c/0x1120 [ 62.326045][ T21] ? process_one_work+0x1670/0x1670 [ 62.331351][ T21] kthread+0x3b5/0x4a0 [ 62.335415][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 62.340616][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 62.346180][ T21] ret_from_fork+0x1f/0x30 [ 62.350782][ T21] [ 62.353103][ T21] Allocated by task 6878: [ 62.357546][ T21] save_stack+0x1b/0x40 [ 62.361816][ T21] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 62.367442][ T21] kmem_cache_alloc_trace+0x14f/0x2d0 [ 62.372831][ T21] afs_alloc_call+0x4f/0x360 [ 62.377416][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 62.382965][ T21] afs_open_socket+0x294/0x360 [ 62.387807][ T21] afs_net_init+0xab4/0xe90 [ 62.392316][ T21] ops_init+0xaf/0x470 [ 62.396377][ T21] setup_net+0x2d8/0x850 [ 62.400627][ T21] copy_net_ns+0x2cf/0x5e0 [ 62.405214][ T21] create_new_namespaces+0x3f6/0xb10 [ 62.410514][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.417133][ T21] ksys_unshare+0x36c/0x9a0 [ 62.421976][ T21] __x64_sys_unshare+0x2d/0x40 [ 62.427005][ T21] do_syscall_64+0x60/0xe0 [ 62.431430][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.437309][ T21] [ 62.439634][ T21] Freed by task 21: [ 62.443448][ T21] save_stack+0x1b/0x40 [ 62.448040][ T21] __kasan_slab_free+0xf5/0x140 [ 62.453148][ T21] kfree+0x103/0x2c0 [ 62.457219][ T21] afs_put_call+0x345/0x440 [ 62.461904][ T21] rxrpc_discard_prealloc+0x75a/0xab0 [ 62.467275][ T21] rxrpc_listen+0x11c/0x330 [ 62.471777][ T21] afs_close_socket+0x95/0x320 [ 62.476537][ T21] afs_net_exit+0x1c4/0x310 [ 62.481237][ T21] ops_exit_list+0xb0/0x160 [ 62.485743][ T21] cleanup_net+0x4ea/0xa00 [ 62.490154][ T21] process_one_work+0x94c/0x1670 [ 62.495201][ T21] worker_thread+0x64c/0x1120 [ 62.499883][ T21] kthread+0x3b5/0x4a0 [ 62.503960][ T21] ret_from_fork+0x1f/0x30 [ 62.508365][ T21] [ 62.510693][ T21] The buggy address belongs to the object at ffff8880a794f800 [ 62.510693][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 62.524745][ T21] The buggy address is located 484 bytes inside of [ 62.524745][ T21] 1024-byte region [ffff8880a794f800, ffff8880a794fc00) [ 62.538106][ T21] The buggy address belongs to the page: [ 62.543776][ T21] page:ffffea00029e53c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.552877][ T21] flags: 0xfffe0000000200(slab) [ 62.558082][ T21] raw: 00fffe0000000200 ffffea00024f6cc8 ffffea00027f7d88 ffff8880aa000c40 [ 62.566845][ T21] raw: 0000000000000000 ffff8880a794f000 0000000100000002 0000000000000000 [ 62.575419][ T21] page dumped because: kasan: bad access detected [ 62.581825][ T21] [ 62.584149][ T21] Memory state around the buggy address: [ 62.589786][ T21] ffff8880a794f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.597845][ T21] ffff8880a794f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.606248][ T21] >ffff8880a794f980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.614299][ T21] ^ [ 62.621579][ T21] ffff8880a794fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.629728][ T21] ffff8880a794fa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.637782][ T21] ================================================================== [ 62.645832][ T21] Disabling lock debugging due to kernel taint [ 62.652025][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 62.658610][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc2-syzkaller #0 [ 62.668222][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.678446][ T21] Workqueue: netns cleanup_net [ 62.683195][ T21] Call Trace: [ 62.686476][ T21] dump_stack+0x18f/0x20d [ 62.690804][ T21] ? afs_wake_up_async_call+0x340/0x4a0 [ 62.696338][ T21] ? afs_put_call+0x440/0x440 [ 62.701120][ T21] panic+0x2e3/0x75c [ 62.705125][ T21] ? __warn_printk+0xf3/0xf3 [ 62.709718][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.715262][ T21] ? trace_hardirqs_on+0x55/0x220 [ 62.720496][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.726302][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.733838][ T21] ? afs_put_call+0x440/0x440 [ 62.738942][ T21] end_report+0x4d/0x53 [ 62.743476][ T21] kasan_report.cold+0xd/0x37 [ 62.748151][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 62.753833][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 62.759199][ T21] ? afs_close_socket+0x320/0x320 [ 62.764218][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.769322][ T21] ? afs_put_call+0x440/0x440 [ 62.773992][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.780667][ T21] rxrpc_call_completed+0xd0/0xf0 [ 62.785770][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 62.791139][ T21] ? lock_sock_nested+0x94/0x110 [ 62.796069][ T21] rxrpc_listen+0x11c/0x330 [ 62.800573][ T21] afs_close_socket+0x95/0x320 [ 62.805453][ T21] ? afs_purge_servers+0x181/0x330 [ 62.810572][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.816028][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.821337][ T21] afs_net_exit+0x1c4/0x310 [ 62.825855][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 62.831570][ T21] ops_exit_list+0xb0/0x160 [ 62.836068][ T21] cleanup_net+0x4ea/0xa00 [ 62.840660][ T21] ? __schedule+0x887/0x1eb0 [ 62.845243][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 62.850819][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.856625][ T21] process_one_work+0x94c/0x1670 [ 62.861653][ T21] ? lock_release+0x8d0/0x8d0 [ 62.866510][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 62.871883][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.876829][ T21] worker_thread+0x64c/0x1120 [ 62.881594][ T21] ? process_one_work+0x1670/0x1670 [ 62.886878][ T21] kthread+0x3b5/0x4a0 [ 62.893293][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 62.900480][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 62.905694][ T21] ret_from_fork+0x1f/0x30 [ 62.911675][ T21] Kernel Offset: disabled [ 62.916194][ T21] Rebooting in 86400 seconds..