[ 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 '10.128.10.58' (ECDSA) to the list of known hosts. 2020/06/19 08:55:47 fuzzer started 2020/06/19 08:55:48 connecting to host at 10.128.0.26:40211 2020/06/19 08:55:48 checking machine... 2020/06/19 08:55:48 checking revisions... 2020/06/19 08:55:48 testing simple program... syzkaller login: [ 61.464261][ T6813] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 08:55:48 building call list... [ 61.793779][ T21] tipc: TX() has been purged, node left! [ 62.306009][ T21] ================================================================== [ 62.314424][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.322427][ T21] Write of size 1 at addr ffff88809fd171e4 by task kworker/u4:1/21 [ 62.330330][ T21] [ 62.332669][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.340918][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.350976][ T21] Workqueue: netns cleanup_net [ 62.355739][ T21] Call Trace: [ 62.359031][ T21] dump_stack+0x18f/0x20d [ 62.363363][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.368929][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.374477][ T21] ? afs_put_call+0xa40/0xa40 [ 62.379155][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.386191][ T21] ? vprintk_func+0x97/0x1a6 [ 62.390792][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.396601][ T21] kasan_report.cold+0x1f/0x37 [ 62.401371][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.407000][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.412544][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.417913][ T21] ? afs_close_socket+0x320/0x320 [ 62.423030][ T21] ? afs_put_call+0xa40/0xa40 [ 62.427709][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.432831][ T21] ? afs_put_call+0xa40/0xa40 [ 62.437516][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.443953][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.449001][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 62.454379][ T21] ? lock_sock_nested+0x94/0x110 [ 62.459347][ T21] rxrpc_listen+0x147/0x360 [ 62.463856][ T21] afs_close_socket+0x95/0x320 [ 62.468617][ T21] ? afs_purge_servers+0x16d/0x300 [ 62.474255][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.479718][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.485011][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.490678][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.496401][ T21] afs_net_exit+0x1bc/0x310 [ 62.500908][ T21] ? afs_net_init+0xe30/0xe30 [ 62.505581][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.510700][ T21] cleanup_net+0x511/0xa50 [ 62.515132][ T21] ? unregister_pernet_device+0x70/0x70 [ 62.520682][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.526695][ T21] process_one_work+0x965/0x1690 [ 62.531657][ T21] ? lock_release+0x800/0x800 [ 62.536506][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.541880][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.546832][ T21] worker_thread+0x96/0xe10 [ 62.551357][ T21] ? process_one_work+0x1690/0x1690 [ 62.556564][ T21] kthread+0x3b5/0x4a0 [ 62.560648][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.566365][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.572087][ T21] ret_from_fork+0x1f/0x30 [ 62.576541][ T21] [ 62.578892][ T21] Allocated by task 6813: [ 62.583743][ T21] save_stack+0x1b/0x40 [ 62.587900][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.593527][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.598894][ T21] afs_alloc_call+0x55/0x630 [ 62.603482][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 62.608937][ T21] afs_open_socket+0x292/0x360 [ 62.613700][ T21] afs_net_init+0xa6c/0xe30 [ 62.618202][ T21] ops_init+0xaf/0x420 [ 62.622271][ T21] setup_net+0x2de/0x860 [ 62.626509][ T21] copy_net_ns+0x293/0x590 [ 62.630922][ T21] create_new_namespaces+0x3fb/0xb30 [ 62.636207][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.641835][ T21] ksys_unshare+0x43d/0x8e0 [ 62.646332][ T21] __x64_sys_unshare+0x2d/0x40 [ 62.651091][ T21] do_syscall_64+0x60/0xe0 [ 62.655514][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.661393][ T21] [ 62.663719][ T21] Freed by task 21: [ 62.667527][ T21] save_stack+0x1b/0x40 [ 62.671684][ T21] __kasan_slab_free+0xf7/0x140 [ 62.676564][ T21] kfree+0x109/0x2b0 [ 62.680461][ T21] afs_put_call+0x585/0xa40 [ 62.684963][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 62.690329][ T21] rxrpc_listen+0x147/0x360 [ 62.694847][ T21] afs_close_socket+0x95/0x320 [ 62.699623][ T21] afs_net_exit+0x1bc/0x310 [ 62.704123][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.709239][ T21] cleanup_net+0x511/0xa50 [ 62.713678][ T21] process_one_work+0x965/0x1690 [ 62.718639][ T21] worker_thread+0x96/0xe10 [ 62.723146][ T21] kthread+0x3b5/0x4a0 [ 62.727235][ T21] ret_from_fork+0x1f/0x30 [ 62.731679][ T21] [ 62.734195][ T21] The buggy address belongs to the object at ffff88809fd17000 [ 62.734195][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 62.749753][ T21] The buggy address is located 484 bytes inside of [ 62.749753][ T21] 1024-byte region [ffff88809fd17000, ffff88809fd17400) [ 62.763289][ T21] The buggy address belongs to the page: [ 62.768924][ T21] page:ffffea00027f45c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88809fd17800 [ 62.779424][ T21] flags: 0xfffe0000000200(slab) [ 62.784368][ T21] raw: 00fffe0000000200 ffffea00028fe948 ffffea0002984cc8 ffff8880aa000c40 [ 62.792963][ T21] raw: ffff88809fd17800 ffff88809fd17000 0000000100000001 0000000000000000 [ 62.801545][ T21] page dumped because: kasan: bad access detected [ 62.807964][ T21] [ 62.810287][ T21] Memory state around the buggy address: [ 62.815918][ T21] ffff88809fd17080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.823979][ T21] ffff88809fd17100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.832300][ T21] >ffff88809fd17180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.840351][ T21] ^ [ 62.847562][ T21] ffff88809fd17200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.855625][ T21] ffff88809fd17280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.863680][ T21] ================================================================== [ 62.871732][ T21] Disabling lock debugging due to kernel taint [ 62.877951][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 62.884544][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.894154][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.904216][ T21] Workqueue: netns cleanup_net [ 62.908967][ T21] Call Trace: [ 62.912473][ T21] dump_stack+0x18f/0x20d [ 62.916800][ T21] ? afs_wake_up_async_call+0x680/0x770 [ 62.922341][ T21] ? afs_put_call+0xa40/0xa40 [ 62.927008][ T21] panic+0x2e3/0x75c [ 62.930899][ T21] ? __warn_printk+0xf3/0xf3 [ 62.935483][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.941633][ T21] ? trace_hardirqs_on+0x55/0x220 [ 62.946670][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.952233][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.957768][ T21] ? afs_put_call+0xa40/0xa40 [ 62.962437][ T21] end_report+0x4d/0x53 [ 62.966588][ T21] kasan_report.cold+0xd/0x37 [ 62.971801][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.977469][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.983887][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.989251][ T21] ? afs_close_socket+0x320/0x320 [ 62.994272][ T21] ? afs_put_call+0xa40/0xa40 [ 62.999092][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 63.004215][ T21] ? afs_put_call+0xa40/0xa40 [ 63.008900][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.015314][ T21] rxrpc_call_completed+0xca/0xf0 [ 63.020338][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 63.025713][ T21] ? lock_sock_nested+0x94/0x110 [ 63.030645][ T21] rxrpc_listen+0x147/0x360 [ 63.035149][ T21] afs_close_socket+0x95/0x320 [ 63.039906][ T21] ? afs_purge_servers+0x16d/0x300 [ 63.045015][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 63.050481][ T21] ? init_wait_var_entry+0x200/0x200 [ 63.055759][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.061390][ T21] ? check_preemption_disabled+0x38/0x220 [ 63.067108][ T21] afs_net_exit+0x1bc/0x310 [ 63.071604][ T21] ? afs_net_init+0xe30/0xe30 [ 63.076291][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 63.081436][ T21] cleanup_net+0x511/0xa50 [ 63.085866][ T21] ? unregister_pernet_device+0x70/0x70 [ 63.091434][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.097413][ T21] process_one_work+0x965/0x1690 [ 63.102452][ T21] ? lock_release+0x800/0x800 [ 63.107126][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.112493][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 63.117429][ T21] worker_thread+0x96/0xe10 [ 63.121932][ T21] ? process_one_work+0x1690/0x1690 [ 63.127211][ T21] kthread+0x3b5/0x4a0 [ 63.131301][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.137013][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.142727][ T21] ret_from_fork+0x1f/0x30 [ 63.148429][ T21] Kernel Offset: disabled [ 63.152799][ T21] Rebooting in 86400 seconds..