[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ OK ] Started Getty on tty1. [ OK ] Started Getty on tty2. [ 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... Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.15.207' (ECDSA) to the list of known hosts. 2020/06/25 22:20:35 fuzzer started 2020/06/25 22:20:36 connecting to host at 10.128.0.26:44885 2020/06/25 22:20:36 checking machine... 2020/06/25 22:20:36 checking revisions... 2020/06/25 22:20:36 testing simple program... syzkaller login: [ 60.103508][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 22:20:36 building call list... [ 60.477151][ T25] tipc: TX() has been purged, node left! [ 60.989518][ T25] ================================================================== [ 60.997748][ T25] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 61.005636][ T25] Write of size 1 at addr ffff88808df351e4 by task kworker/u4:2/25 [ 61.013510][ T25] [ 61.015841][ T25] CPU: 0 PID: 25 Comm: kworker/u4:2 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.024070][ T25] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.034392][ T25] Workqueue: netns cleanup_net [ 61.039175][ T25] Call Trace: [ 61.042464][ T25] dump_stack+0x18f/0x20d [ 61.046796][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.052338][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.057879][ T25] ? afs_put_call+0x440/0x440 [ 61.062558][ T25] print_address_description.constprop.0.cold+0xae/0x436 [ 61.069585][ T25] ? vprintk_func+0x97/0x1a6 [ 61.074179][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.079721][ T25] kasan_report.cold+0x1f/0x37 [ 61.084486][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.090030][ T25] afs_wake_up_async_call+0x430/0x4a0 [ 61.095423][ T25] ? afs_close_socket+0x320/0x320 [ 61.100720][ T25] rxrpc_notify_socket+0x1db/0x5d0 [ 61.105839][ T25] ? afs_put_call+0x440/0x440 [ 61.110517][ T25] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.116932][ T25] rxrpc_call_completed+0xd0/0xf0 [ 61.121956][ T25] rxrpc_discard_prealloc+0x777/0xab0 [ 61.127327][ T25] ? lock_sock_nested+0x94/0x110 [ 61.132268][ T25] rxrpc_listen+0x11c/0x330 [ 61.136770][ T25] afs_close_socket+0x95/0x320 [ 61.141529][ T25] ? afs_purge_servers+0x16d/0x300 [ 61.146750][ T25] ? afs_rx_discard_new_call+0x50/0x50 [ 61.152211][ T25] ? init_wait_var_entry+0x200/0x200 [ 61.157505][ T25] ? check_preemption_disabled+0x38/0x220 [ 61.163226][ T25] afs_net_exit+0x1bc/0x310 [ 61.167730][ T25] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.173373][ T25] ops_exit_list+0xb0/0x160 [ 61.177882][ T25] cleanup_net+0x4ea/0xa00 [ 61.182304][ T25] ? __schedule+0x887/0x1eb0 [ 61.186892][ T25] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.192353][ T25] ? check_preemption_disabled+0x38/0x220 [ 61.198081][ T25] process_one_work+0x94c/0x1670 [ 61.203029][ T25] ? lock_release+0x8d0/0x8d0 [ 61.207713][ T25] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.213093][ T25] ? rwlock_bug.part.0+0x90/0x90 [ 61.218043][ T25] worker_thread+0x64c/0x1120 [ 61.222771][ T25] ? process_one_work+0x1670/0x1670 [ 61.227970][ T25] kthread+0x3b5/0x4a0 [ 61.232034][ T25] ? __kthread_bind_mask+0xc0/0xc0 [ 61.237139][ T25] ? __kthread_bind_mask+0xc0/0xc0 [ 61.242255][ T25] ret_from_fork+0x1f/0x30 [ 61.246693][ T25] [ 61.249015][ T25] Allocated by task 6820: [ 61.253346][ T25] save_stack+0x1b/0x40 [ 61.257500][ T25] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 61.263139][ T25] kmem_cache_alloc_trace+0x14f/0x2d0 [ 61.268517][ T25] afs_alloc_call+0x4f/0x360 [ 61.273111][ T25] afs_charge_preallocation+0xe9/0x2d0 [ 61.278568][ T25] afs_open_socket+0x294/0x360 [ 61.283330][ T25] afs_net_init+0xa6c/0xe30 [ 61.287836][ T25] ops_init+0xaf/0x470 [ 61.291896][ T25] setup_net+0x2d8/0x850 [ 61.296133][ T25] copy_net_ns+0x2cf/0x5e0 [ 61.300545][ T25] create_new_namespaces+0x3f6/0xb10 [ 61.305845][ T25] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.311474][ T25] ksys_unshare+0x36c/0x9a0 [ 61.315971][ T25] __x64_sys_unshare+0x2d/0x40 [ 61.320733][ T25] do_syscall_64+0x60/0xe0 [ 61.325148][ T25] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.331046][ T25] [ 61.333373][ T25] Freed by task 25: [ 61.337180][ T25] save_stack+0x1b/0x40 [ 61.341330][ T25] __kasan_slab_free+0xf5/0x140 [ 61.346177][ T25] kfree+0x103/0x2c0 [ 61.350083][ T25] afs_put_call+0x345/0x440 [ 61.354590][ T25] rxrpc_discard_prealloc+0x75a/0xab0 [ 61.359968][ T25] rxrpc_listen+0x11c/0x330 [ 61.364466][ T25] afs_close_socket+0x95/0x320 [ 61.369224][ T25] afs_net_exit+0x1bc/0x310 [ 61.373722][ T25] ops_exit_list+0xb0/0x160 [ 61.378219][ T25] cleanup_net+0x4ea/0xa00 [ 61.382630][ T25] process_one_work+0x94c/0x1670 [ 61.387560][ T25] worker_thread+0x64c/0x1120 [ 61.392228][ T25] kthread+0x3b5/0x4a0 [ 61.396294][ T25] ret_from_fork+0x1f/0x30 [ 61.400694][ T25] [ 61.403019][ T25] The buggy address belongs to the object at ffff88808df35000 [ 61.403019][ T25] which belongs to the cache kmalloc-1k of size 1024 [ 61.417071][ T25] The buggy address is located 484 bytes inside of [ 61.417071][ T25] 1024-byte region [ffff88808df35000, ffff88808df35400) [ 61.430936][ T25] The buggy address belongs to the page: [ 61.436562][ T25] page:ffffea000237cd40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.445659][ T25] flags: 0xfffe0000000200(slab) [ 61.450514][ T25] raw: 00fffe0000000200 ffffea0002686748 ffffea0002516848 ffff8880aa000c40 [ 61.459096][ T25] raw: 0000000000000000 ffff88808df35000 0000000100000002 0000000000000000 [ 61.467669][ T25] page dumped because: kasan: bad access detected [ 61.474104][ T25] [ 61.476424][ T25] Memory state around the buggy address: [ 61.482055][ T25] ffff88808df35080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.490111][ T25] ffff88808df35100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.498166][ T25] >ffff88808df35180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.506218][ T25] ^ [ 61.513407][ T25] ffff88808df35200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.521464][ T25] ffff88808df35280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.529518][ T25] ================================================================== [ 61.537568][ T25] Disabling lock debugging due to kernel taint [ 61.543752][ T25] Kernel panic - not syncing: panic_on_warn set ... [ 61.550342][ T25] CPU: 0 PID: 25 Comm: kworker/u4:2 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.560994][ T25] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.571055][ T25] Workqueue: netns cleanup_net [ 61.575807][ T25] Call Trace: [ 61.579107][ T25] dump_stack+0x18f/0x20d [ 61.583435][ T25] ? afs_wake_up_async_call+0x400/0x4a0 [ 61.588982][ T25] ? afs_put_call+0x440/0x440 [ 61.593661][ T25] panic+0x2e3/0x75c [ 61.597552][ T25] ? __warn_printk+0xf3/0xf3 [ 61.602144][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.607687][ T25] ? trace_hardirqs_on+0x55/0x220 [ 61.612706][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.618244][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.623778][ T25] ? afs_put_call+0x440/0x440 [ 61.628447][ T25] end_report+0x4d/0x53 [ 61.632595][ T25] kasan_report.cold+0xd/0x37 [ 61.637263][ T25] ? afs_wake_up_async_call+0x430/0x4a0 [ 61.642798][ T25] afs_wake_up_async_call+0x430/0x4a0 [ 61.648163][ T25] ? afs_close_socket+0x320/0x320 [ 61.653184][ T25] rxrpc_notify_socket+0x1db/0x5d0 [ 61.658291][ T25] ? afs_put_call+0x440/0x440 [ 61.662962][ T25] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.669895][ T25] rxrpc_call_completed+0xd0/0xf0 [ 61.674911][ T25] rxrpc_discard_prealloc+0x777/0xab0 [ 61.680276][ T25] ? lock_sock_nested+0x94/0x110 [ 61.685208][ T25] rxrpc_listen+0x11c/0x330 [ 61.689704][ T25] afs_close_socket+0x95/0x320 [ 61.694458][ T25] ? afs_purge_servers+0x16d/0x300 [ 61.699560][ T25] ? afs_rx_discard_new_call+0x50/0x50 [ 61.705009][ T25] ? init_wait_var_entry+0x200/0x200 [ 61.710291][ T25] ? check_preemption_disabled+0x38/0x220 [ 61.716024][ T25] afs_net_exit+0x1bc/0x310 [ 61.720525][ T25] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 61.726233][ T25] ops_exit_list+0xb0/0x160 [ 61.730730][ T25] cleanup_net+0x4ea/0xa00 [ 61.735136][ T25] ? __schedule+0x887/0x1eb0 [ 61.739715][ T25] ? ops_free_list.part.0+0x3d0/0x3d0 [ 61.745080][ T25] ? check_preemption_disabled+0x38/0x220 [ 61.750793][ T25] process_one_work+0x94c/0x1670 [ 61.755724][ T25] ? lock_release+0x8d0/0x8d0 [ 61.760391][ T25] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.765756][ T25] ? rwlock_bug.part.0+0x90/0x90 [ 61.770687][ T25] worker_thread+0x64c/0x1120 [ 61.775361][ T25] ? process_one_work+0x1670/0x1670 [ 61.780549][ T25] kthread+0x3b5/0x4a0 [ 61.784632][ T25] ? __kthread_bind_mask+0xc0/0xc0 [ 61.789734][ T25] ? __kthread_bind_mask+0xc0/0xc0 [ 61.794838][ T25] ret_from_fork+0x1f/0x30 [ 61.800552][ T25] Kernel Offset: disabled [ 61.804866][ T25] Rebooting in 86400 seconds..