[ OK ] Started Getty on tty4. [ OK ] Started Getty on tty3. [ 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 '10.128.1.59' (ECDSA) to the list of known hosts. 2020/06/19 02:00:43 fuzzer started 2020/06/19 02:00:43 connecting to host at 10.128.0.26:35625 2020/06/19 02:00:43 checking machine... 2020/06/19 02:00:43 checking revisions... 2020/06/19 02:00:43 testing simple program... syzkaller login: [ 59.794609][ T6829] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 02:00:44 building call list... [ 60.115564][ T7] tipc: TX() has been purged, node left! [ 60.637731][ T7] ================================================================== [ 60.646014][ T7] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 60.653908][ T7] Write of size 1 at addr ffff888095a709e4 by task kworker/u4:0/7 [ 60.661785][ T7] [ 60.664117][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.672428][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.682485][ T7] Workqueue: netns cleanup_net [ 60.687262][ T7] Call Trace: [ 60.690554][ T7] dump_stack+0x18f/0x20d [ 60.694892][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.700432][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.705970][ T7] ? afs_put_call+0xa40/0xa40 [ 60.710654][ T7] print_address_description.constprop.0.cold+0xd3/0x413 [ 60.717682][ T7] ? vprintk_func+0x97/0x1a6 [ 60.722316][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.727858][ T7] kasan_report.cold+0x1f/0x37 [ 60.732653][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 60.738308][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 60.743850][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 60.749219][ T7] ? afs_close_socket+0x320/0x320 [ 60.754252][ T7] ? afs_put_call+0xa40/0xa40 [ 60.758927][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 60.764042][ T7] ? afs_put_call+0xa40/0xa40 [ 60.768714][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.775128][ T7] rxrpc_call_completed+0xca/0xf0 [ 60.780157][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 60.785532][ T7] ? lock_sock_nested+0x94/0x110 [ 60.790468][ T7] rxrpc_listen+0x147/0x360 [ 60.794974][ T7] afs_close_socket+0x95/0x320 [ 60.799733][ T7] ? afs_purge_servers+0x16d/0x300 [ 60.804844][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 60.810324][ T7] ? init_wait_var_entry+0x200/0x200 [ 60.815619][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 60.821261][ T7] ? check_preemption_disabled+0x38/0x220 [ 60.827080][ T7] afs_net_exit+0x1bc/0x310 [ 60.831620][ T7] ? afs_net_init+0xe30/0xe30 [ 60.836314][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 60.841463][ T7] cleanup_net+0x511/0xa50 [ 60.845887][ T7] ? unregister_pernet_device+0x70/0x70 [ 60.851436][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 60.857427][ T7] process_one_work+0x965/0x1690 [ 60.862377][ T7] ? lock_release+0x800/0x800 [ 60.867053][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 60.872616][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 60.877578][ T7] worker_thread+0x96/0xe10 [ 60.882117][ T7] ? process_one_work+0x1690/0x1690 [ 60.887399][ T7] kthread+0x3b5/0x4a0 [ 60.891481][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.897210][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 60.902941][ T7] ret_from_fork+0x1f/0x30 [ 60.907366][ T7] [ 60.909702][ T7] Allocated by task 6829: [ 60.914034][ T7] save_stack+0x1b/0x40 [ 60.918195][ T7] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 60.923827][ T7] kmem_cache_alloc_trace+0x153/0x7d0 [ 60.929197][ T7] afs_alloc_call+0x55/0x630 [ 60.933797][ T7] afs_charge_preallocation+0xe9/0x2d0 [ 60.939252][ T7] afs_open_socket+0x292/0x360 [ 60.944143][ T7] afs_net_init+0xa6c/0xe30 [ 60.948646][ T7] ops_init+0xaf/0x420 [ 60.952710][ T7] setup_net+0x2de/0x860 [ 60.958189][ T7] copy_net_ns+0x293/0x590 [ 60.962610][ T7] create_new_namespaces+0x3fb/0xb30 [ 60.967893][ T7] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 60.973525][ T7] ksys_unshare+0x43d/0x8e0 [ 60.978459][ T7] __ia32_sys_unshare+0x2c/0x40 [ 60.983304][ T7] do_syscall_32_irqs_on+0x3f/0x60 [ 60.988429][ T7] do_fast_syscall_32+0x7f/0x120 [ 60.993379][ T7] entry_SYSENTER_compat+0x6d/0x7c [ 60.998478][ T7] [ 61.000802][ T7] Freed by task 7: [ 61.004526][ T7] save_stack+0x1b/0x40 [ 61.008676][ T7] __kasan_slab_free+0xf7/0x140 [ 61.013518][ T7] kfree+0x109/0x2b0 [ 61.017407][ T7] afs_put_call+0x585/0xa40 [ 61.021993][ T7] rxrpc_discard_prealloc+0x764/0xab0 [ 61.027359][ T7] rxrpc_listen+0x147/0x360 [ 61.031951][ T7] afs_close_socket+0x95/0x320 [ 61.036712][ T7] afs_net_exit+0x1bc/0x310 [ 61.041207][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 61.046333][ T7] cleanup_net+0x511/0xa50 [ 61.050751][ T7] process_one_work+0x965/0x1690 [ 61.055842][ T7] worker_thread+0x96/0xe10 [ 61.060350][ T7] kthread+0x3b5/0x4a0 [ 61.064436][ T7] ret_from_fork+0x1f/0x30 [ 61.068855][ T7] [ 61.071200][ T7] The buggy address belongs to the object at ffff888095a70800 [ 61.071200][ T7] which belongs to the cache kmalloc-1k of size 1024 [ 61.085526][ T7] The buggy address is located 484 bytes inside of [ 61.085526][ T7] 1024-byte region [ffff888095a70800, ffff888095a70c00) [ 61.098960][ T7] The buggy address belongs to the page: [ 61.105049][ T7] page:ffffea0002569c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.114368][ T7] flags: 0xfffe0000000200(slab) [ 61.119414][ T7] raw: 00fffe0000000200 ffffea00025698c8 ffffea00024d3148 ffff8880aa000c40 [ 61.128018][ T7] raw: 0000000000000000 ffff888095a70000 0000000100000002 0000000000000000 [ 61.136695][ T7] page dumped because: kasan: bad access detected [ 61.143103][ T7] [ 61.145425][ T7] Memory state around the buggy address: [ 61.151072][ T7] ffff888095a70880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.159144][ T7] ffff888095a70900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.167392][ T7] >ffff888095a70980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.175635][ T7] ^ [ 61.182832][ T7] ffff888095a70a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.190899][ T7] ffff888095a70a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 61.198948][ T7] ================================================================== [ 61.207000][ T7] Disabling lock debugging due to kernel taint [ 61.213203][ T7] Kernel panic - not syncing: panic_on_warn set ... [ 61.219784][ T7] CPU: 0 PID: 7 Comm: kworker/u4:0 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 61.229306][ T7] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.239394][ T7] Workqueue: netns cleanup_net [ 61.244141][ T7] Call Trace: [ 61.247454][ T7] dump_stack+0x18f/0x20d [ 61.251779][ T7] ? afs_wake_up_async_call+0x670/0x770 [ 61.257312][ T7] ? afs_put_call+0xa40/0xa40 [ 61.261983][ T7] panic+0x2e3/0x75c [ 61.266484][ T7] ? __warn_printk+0xf3/0xf3 [ 61.271089][ T7] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 61.277254][ T7] ? trace_hardirqs_on+0x55/0x220 [ 61.282278][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.287821][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.293448][ T7] ? afs_put_call+0xa40/0xa40 [ 61.298132][ T7] end_report+0x4d/0x53 [ 61.302285][ T7] kasan_report.cold+0xd/0x37 [ 61.306962][ T7] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.312599][ T7] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.318162][ T7] afs_wake_up_async_call+0x6aa/0x770 [ 61.323535][ T7] ? afs_close_socket+0x320/0x320 [ 61.328548][ T7] ? afs_put_call+0xa40/0xa40 [ 61.333220][ T7] rxrpc_notify_socket+0x1db/0x5d0 [ 61.338330][ T7] ? afs_put_call+0xa40/0xa40 [ 61.343008][ T7] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.349422][ T7] rxrpc_call_completed+0xca/0xf0 [ 61.354447][ T7] rxrpc_discard_prealloc+0x781/0xab0 [ 61.359811][ T7] ? lock_sock_nested+0x94/0x110 [ 61.364747][ T7] rxrpc_listen+0x147/0x360 [ 61.369248][ T7] afs_close_socket+0x95/0x320 [ 61.374009][ T7] ? afs_purge_servers+0x16d/0x300 [ 61.379117][ T7] ? afs_rx_discard_new_call+0x50/0x50 [ 61.384590][ T7] ? init_wait_var_entry+0x200/0x200 [ 61.389867][ T7] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.395493][ T7] ? check_preemption_disabled+0x38/0x220 [ 61.401229][ T7] afs_net_exit+0x1bc/0x310 [ 61.405725][ T7] ? afs_net_init+0xe30/0xe30 [ 61.410393][ T7] ops_exit_list.isra.0+0xa8/0x150 [ 61.415501][ T7] cleanup_net+0x511/0xa50 [ 61.419908][ T7] ? unregister_pernet_device+0x70/0x70 [ 61.425448][ T7] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.431509][ T7] process_one_work+0x965/0x1690 [ 61.436444][ T7] ? lock_release+0x800/0x800 [ 61.441110][ T7] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.446474][ T7] ? rwlock_bug.part.0+0x90/0x90 [ 61.451426][ T7] worker_thread+0x96/0xe10 [ 61.455926][ T7] ? process_one_work+0x1690/0x1690 [ 61.461117][ T7] kthread+0x3b5/0x4a0 [ 61.465189][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.470900][ T7] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.476698][ T7] ret_from_fork+0x1f/0x30 [ 61.482703][ T7] Kernel Offset: disabled [ 61.487093][ T7] Rebooting in 86400 seconds..