[ 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. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.50' (ECDSA) to the list of known hosts. 2020/06/17 22:29:29 fuzzer started 2020/06/17 22:29:29 connecting to host at 10.128.0.26:46805 2020/06/17 22:29:29 checking machine... 2020/06/17 22:29:29 checking revisions... 2020/06/17 22:29:29 testing simple program... syzkaller login: [ 60.600073][ T6822] IPVS: ftp: loaded support on port[0] = 21 2020/06/17 22:29:30 building call list... [ 60.997930][ T6763] tipc: TX() has been purged, node left! [ 61.520412][ T6763] ================================================================== [ 61.528629][ T6763] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.536521][ T6763] Write of size 1 at addr ffff8880a131e9e4 by task kworker/u4:10/6763 [ 61.544656][ T6763] [ 61.546989][ T6763] CPU: 1 PID: 6763 Comm: kworker/u4:10 Not tainted 5.8.0-rc1-syzkaller #0 [ 61.555495][ T6763] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.565570][ T6763] Workqueue: netns cleanup_net [ 61.570323][ T6763] Call Trace: [ 61.573620][ T6763] dump_stack+0x18f/0x20d [ 61.577953][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.583493][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.589031][ T6763] ? afs_put_call+0xa40/0xa40 [ 61.593723][ T6763] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.600749][ T6763] ? vprintk_func+0x97/0x1a6 [ 61.605342][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.610882][ T6763] kasan_report.cold+0x1f/0x37 [ 61.615671][ T6763] ? rcu_read_lock_held_common+0x51/0xa0 [ 61.621296][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.626843][ T6763] afs_wake_up_async_call+0x6aa/0x770 [ 61.632208][ T6763] ? afs_close_socket+0x320/0x320 [ 61.637241][ T6763] ? afs_put_call+0xa40/0xa40 [ 61.641915][ T6763] rxrpc_notify_socket+0x1db/0x5d0 [ 61.647026][ T6763] ? afs_put_call+0xa40/0xa40 [ 61.651701][ T6763] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.658114][ T6763] rxrpc_call_completed+0xca/0xf0 [ 61.663139][ T6763] rxrpc_discard_prealloc+0x781/0xab0 [ 61.668522][ T6763] ? lock_sock_nested+0x94/0x110 [ 61.673721][ T6763] rxrpc_listen+0x147/0x360 [ 61.678230][ T6763] afs_close_socket+0x95/0x320 [ 61.682991][ T6763] ? afs_purge_servers+0x16d/0x300 [ 61.688103][ T6763] ? afs_rx_discard_new_call+0x50/0x50 [ 61.693562][ T6763] ? init_wait_var_entry+0x200/0x200 [ 61.698848][ T6763] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.704496][ T6763] ? check_preemption_disabled+0x38/0x220 [ 61.710246][ T6763] afs_net_exit+0x1bc/0x310 [ 61.714746][ T6763] ? afs_net_init+0xe30/0xe30 [ 61.719422][ T6763] ops_exit_list.isra.0+0xa8/0x150 [ 61.724532][ T6763] cleanup_net+0x511/0xa50 [ 61.728948][ T6763] ? unregister_pernet_device+0x70/0x70 [ 61.734523][ T6763] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.740510][ T6763] process_one_work+0x965/0x1690 [ 61.745454][ T6763] ? lock_release+0x800/0x800 [ 61.750149][ T6763] ? pwq_dec_nr_in_flight+0x310/0x310 [ 61.755521][ T6763] ? rwlock_bug.part.0+0x90/0x90 [ 61.760468][ T6763] worker_thread+0x96/0xe10 [ 61.764982][ T6763] ? process_one_work+0x1690/0x1690 [ 61.770177][ T6763] kthread+0x3b5/0x4a0 [ 61.774248][ T6763] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.779972][ T6763] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 61.785716][ T6763] ret_from_fork+0x1f/0x30 [ 61.790138][ T6763] [ 61.792474][ T6763] Allocated by task 6822: [ 61.796800][ T6763] save_stack+0x1b/0x40 [ 61.800953][ T6763] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 61.806602][ T6763] kmem_cache_alloc_trace+0x153/0x7d0 [ 61.811967][ T6763] afs_alloc_call+0x55/0x630 [ 61.816552][ T6763] afs_charge_preallocation+0xe9/0x2d0 [ 61.822005][ T6763] afs_open_socket+0x292/0x360 [ 61.826772][ T6763] afs_net_init+0xa6c/0xe30 [ 61.831546][ T6763] ops_init+0xaf/0x420 [ 61.835605][ T6763] setup_net+0x2de/0x860 [ 61.839840][ T6763] copy_net_ns+0x293/0x590 [ 61.844256][ T6763] create_new_namespaces+0x3fb/0xb30 [ 61.849535][ T6763] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 61.855160][ T6763] ksys_unshare+0x43d/0x8e0 [ 61.859656][ T6763] __x64_sys_unshare+0x2d/0x40 [ 61.864416][ T6763] do_syscall_64+0x60/0xe0 [ 61.868833][ T6763] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 61.874717][ T6763] [ 61.877045][ T6763] Freed by task 6763: [ 61.881027][ T6763] save_stack+0x1b/0x40 [ 61.885183][ T6763] __kasan_slab_free+0xf7/0x140 [ 61.890031][ T6763] kfree+0x109/0x2b0 [ 61.893921][ T6763] afs_put_call+0x585/0xa40 [ 61.898424][ T6763] rxrpc_discard_prealloc+0x764/0xab0 [ 61.903792][ T6763] rxrpc_listen+0x147/0x360 [ 61.908306][ T6763] afs_close_socket+0x95/0x320 [ 61.913079][ T6763] afs_net_exit+0x1bc/0x310 [ 61.917583][ T6763] ops_exit_list.isra.0+0xa8/0x150 [ 61.922684][ T6763] cleanup_net+0x511/0xa50 [ 61.927093][ T6763] process_one_work+0x965/0x1690 [ 61.932022][ T6763] worker_thread+0x96/0xe10 [ 61.936521][ T6763] kthread+0x3b5/0x4a0 [ 61.940596][ T6763] ret_from_fork+0x1f/0x30 [ 61.944995][ T6763] [ 61.947319][ T6763] The buggy address belongs to the object at ffff8880a131e800 [ 61.947319][ T6763] which belongs to the cache kmalloc-1k of size 1024 [ 61.961419][ T6763] The buggy address is located 484 bytes inside of [ 61.961419][ T6763] 1024-byte region [ffff8880a131e800, ffff8880a131ec00) [ 61.974761][ T6763] The buggy address belongs to the page: [ 61.980910][ T6763] page:ffffea000284c780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 61.990004][ T6763] flags: 0xfffe0000000200(slab) [ 61.994854][ T6763] raw: 00fffe0000000200 ffffea00027e0b48 ffffea0002863348 ffff8880aa000c40 [ 62.003432][ T6763] raw: 0000000000000000 ffff8880a131e000 0000000100000002 0000000000000000 [ 62.012004][ T6763] page dumped because: kasan: bad access detected [ 62.018418][ T6763] [ 62.020741][ T6763] Memory state around the buggy address: [ 62.026364][ T6763] ffff8880a131e880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.034418][ T6763] ffff8880a131e900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.042477][ T6763] >ffff8880a131e980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.050526][ T6763] ^ [ 62.057710][ T6763] ffff8880a131ea00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.065783][ T6763] ffff8880a131ea80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.073834][ T6763] ================================================================== [ 62.081895][ T6763] Disabling lock debugging due to kernel taint [ 62.088102][ T6763] Kernel panic - not syncing: panic_on_warn set ... [ 62.094685][ T6763] CPU: 1 PID: 6763 Comm: kworker/u4:10 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.104556][ T6763] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.114610][ T6763] Workqueue: netns cleanup_net [ 62.119384][ T6763] Call Trace: [ 62.122668][ T6763] dump_stack+0x18f/0x20d [ 62.127003][ T6763] ? afs_wake_up_async_call+0x680/0x770 [ 62.132540][ T6763] ? afs_put_call+0xa40/0xa40 [ 62.137213][ T6763] panic+0x2e3/0x75c [ 62.141113][ T6763] ? __warn_printk+0xf3/0xf3 [ 62.145702][ T6763] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.151857][ T6763] ? trace_hardirqs_on+0x55/0x220 [ 62.156878][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.162418][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.167954][ T6763] ? afs_put_call+0xa40/0xa40 [ 62.172622][ T6763] end_report+0x4d/0x53 [ 62.176767][ T6763] kasan_report.cold+0xd/0x37 [ 62.181460][ T6763] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.187083][ T6763] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.192617][ T6763] afs_wake_up_async_call+0x6aa/0x770 [ 62.197977][ T6763] ? afs_close_socket+0x320/0x320 [ 62.203082][ T6763] ? afs_put_call+0xa40/0xa40 [ 62.207755][ T6763] rxrpc_notify_socket+0x1db/0x5d0 [ 62.212860][ T6763] ? afs_put_call+0xa40/0xa40 [ 62.217532][ T6763] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.223939][ T6763] rxrpc_call_completed+0xca/0xf0 [ 62.228961][ T6763] rxrpc_discard_prealloc+0x781/0xab0 [ 62.234330][ T6763] ? lock_sock_nested+0x94/0x110 [ 62.239265][ T6763] rxrpc_listen+0x147/0x360 [ 62.243762][ T6763] afs_close_socket+0x95/0x320 [ 62.248516][ T6763] ? afs_purge_servers+0x16d/0x300 [ 62.253620][ T6763] ? afs_rx_discard_new_call+0x50/0x50 [ 62.259073][ T6763] ? init_wait_var_entry+0x200/0x200 [ 62.264352][ T6763] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.269976][ T6763] ? check_preemption_disabled+0x38/0x220 [ 62.277684][ T6763] afs_net_exit+0x1bc/0x310 [ 62.282199][ T6763] ? afs_net_init+0xe30/0xe30 [ 62.286872][ T6763] ops_exit_list.isra.0+0xa8/0x150 [ 62.291984][ T6763] cleanup_net+0x511/0xa50 [ 62.296399][ T6763] ? unregister_pernet_device+0x70/0x70 [ 62.301943][ T6763] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.307920][ T6763] process_one_work+0x965/0x1690 [ 62.312878][ T6763] ? lock_release+0x800/0x800 [ 62.317569][ T6763] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.322935][ T6763] ? rwlock_bug.part.0+0x90/0x90 [ 62.327871][ T6763] worker_thread+0x96/0xe10 [ 62.332374][ T6763] ? process_one_work+0x1690/0x1690 [ 62.337567][ T6763] kthread+0x3b5/0x4a0 [ 62.341626][ T6763] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.347360][ T6763] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.353073][ T6763] ret_from_fork+0x1f/0x30 [ 62.358563][ T6763] Kernel Offset: disabled [ 62.362887][ T6763] Rebooting in 86400 seconds..