[ 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 '10.128.0.76' (ECDSA) to the list of known hosts. 2020/06/19 05:16:47 fuzzer started 2020/06/19 05:16:48 connecting to host at 10.128.0.26:34265 2020/06/19 05:16:48 checking machine... 2020/06/19 05:16:48 checking revisions... 2020/06/19 05:16:48 testing simple program... syzkaller login: [ 61.389270][ T6821] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 05:16:48 building call list... [ 61.752849][ T156] tipc: TX() has been purged, node left! [ 62.265234][ T156] ================================================================== [ 62.273499][ T156] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.281385][ T156] Write of size 1 at addr ffff8880a47a21e4 by task kworker/u4:3/156 [ 62.289351][ T156] [ 62.292226][ T156] CPU: 0 PID: 156 Comm: kworker/u4:3 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.300556][ T156] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.310617][ T156] Workqueue: netns cleanup_net [ 62.315385][ T156] Call Trace: [ 62.318680][ T156] dump_stack+0x18f/0x20d [ 62.323010][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.328561][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.334104][ T156] ? afs_put_call+0xa40/0xa40 [ 62.338882][ T156] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.345925][ T156] ? vprintk_func+0x97/0x1a6 [ 62.350523][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.356102][ T156] kasan_report.cold+0x1f/0x37 [ 62.360872][ T156] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.366501][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.372051][ T156] afs_wake_up_async_call+0x6aa/0x770 [ 62.377434][ T156] ? afs_close_socket+0x320/0x320 [ 62.382458][ T156] ? afs_put_call+0xa40/0xa40 [ 62.387133][ T156] rxrpc_notify_socket+0x1db/0x5d0 [ 62.392252][ T156] ? afs_put_call+0xa40/0xa40 [ 62.396947][ T156] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.403363][ T156] rxrpc_call_completed+0xca/0xf0 [ 62.408394][ T156] rxrpc_discard_prealloc+0x781/0xab0 [ 62.413853][ T156] ? lock_sock_nested+0x94/0x110 [ 62.418797][ T156] rxrpc_listen+0x147/0x360 [ 62.423507][ T156] afs_close_socket+0x95/0x320 [ 62.428281][ T156] ? afs_purge_servers+0x16d/0x300 [ 62.433392][ T156] ? afs_rx_discard_new_call+0x50/0x50 [ 62.438852][ T156] ? init_wait_var_entry+0x200/0x200 [ 62.444148][ T156] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.449868][ T156] ? check_preemption_disabled+0x38/0x220 [ 62.455593][ T156] afs_net_exit+0x1bc/0x310 [ 62.460094][ T156] ? afs_net_init+0xe30/0xe30 [ 62.464770][ T156] ops_exit_list.isra.0+0xa8/0x150 [ 62.469885][ T156] cleanup_net+0x511/0xa50 [ 62.474302][ T156] ? unregister_pernet_device+0x70/0x70 [ 62.479852][ T156] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.485841][ T156] process_one_work+0x965/0x1690 [ 62.490789][ T156] ? lock_release+0x800/0x800 [ 62.495466][ T156] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.500853][ T156] ? rwlock_bug.part.0+0x90/0x90 [ 62.505801][ T156] worker_thread+0x96/0xe10 [ 62.510317][ T156] ? process_one_work+0x1690/0x1690 [ 62.515522][ T156] kthread+0x3b5/0x4a0 [ 62.519611][ T156] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.525327][ T156] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.531051][ T156] ret_from_fork+0x1f/0x30 [ 62.535481][ T156] [ 62.537808][ T156] Allocated by task 6821: [ 62.542157][ T156] save_stack+0x1b/0x40 [ 62.546365][ T156] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.551994][ T156] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.557362][ T156] afs_alloc_call+0x55/0x630 [ 62.562382][ T156] afs_charge_preallocation+0xe9/0x2d0 [ 62.567834][ T156] afs_open_socket+0x292/0x360 [ 62.572687][ T156] afs_net_init+0xa6c/0xe30 [ 62.577182][ T156] ops_init+0xaf/0x420 [ 62.581243][ T156] setup_net+0x2de/0x860 [ 62.585490][ T156] copy_net_ns+0x293/0x590 [ 62.589930][ T156] create_new_namespaces+0x3fb/0xb30 [ 62.595216][ T156] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.601108][ T156] ksys_unshare+0x43d/0x8e0 [ 62.605613][ T156] __x64_sys_unshare+0x2d/0x40 [ 62.610382][ T156] do_syscall_64+0x60/0xe0 [ 62.614796][ T156] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.620675][ T156] [ 62.622997][ T156] Freed by task 156: [ 62.626890][ T156] save_stack+0x1b/0x40 [ 62.631043][ T156] __kasan_slab_free+0xf7/0x140 [ 62.635885][ T156] kfree+0x109/0x2b0 [ 62.639778][ T156] afs_put_call+0x585/0xa40 [ 62.644282][ T156] rxrpc_discard_prealloc+0x764/0xab0 [ 62.649657][ T156] rxrpc_listen+0x147/0x360 [ 62.654173][ T156] afs_close_socket+0x95/0x320 [ 62.659512][ T156] afs_net_exit+0x1bc/0x310 [ 62.664711][ T156] ops_exit_list.isra.0+0xa8/0x150 [ 62.669830][ T156] cleanup_net+0x511/0xa50 [ 62.674247][ T156] process_one_work+0x965/0x1690 [ 62.679179][ T156] worker_thread+0x96/0xe10 [ 62.683678][ T156] kthread+0x3b5/0x4a0 [ 62.687744][ T156] ret_from_fork+0x1f/0x30 [ 62.692144][ T156] [ 62.694730][ T156] The buggy address belongs to the object at ffff8880a47a2000 [ 62.694730][ T156] which belongs to the cache kmalloc-1k of size 1024 [ 62.708797][ T156] The buggy address is located 484 bytes inside of [ 62.708797][ T156] 1024-byte region [ffff8880a47a2000, ffff8880a47a2400) [ 62.722754][ T156] The buggy address belongs to the page: [ 62.728387][ T156] page:ffffea000291e880 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.737755][ T156] flags: 0xfffe0000000200(slab) [ 62.742699][ T156] raw: 00fffe0000000200 ffffea0002896ac8 ffffea0002858bc8 ffff8880aa000c40 [ 62.751294][ T156] raw: 0000000000000000 ffff8880a47a2000 0000000100000002 0000000000000000 [ 62.759909][ T156] page dumped because: kasan: bad access detected [ 62.766439][ T156] [ 62.768830][ T156] Memory state around the buggy address: [ 62.774602][ T156] ffff8880a47a2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.782665][ T156] ffff8880a47a2100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.790729][ T156] >ffff8880a47a2180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.799511][ T156] ^ [ 62.806710][ T156] ffff8880a47a2200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.814772][ T156] ffff8880a47a2280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.822824][ T156] ================================================================== [ 62.830885][ T156] Disabling lock debugging due to kernel taint [ 62.837089][ T156] Kernel panic - not syncing: panic_on_warn set ... [ 62.843768][ T156] CPU: 0 PID: 156 Comm: kworker/u4:3 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.853497][ T156] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.863563][ T156] Workqueue: netns cleanup_net [ 62.868336][ T156] Call Trace: [ 62.871632][ T156] dump_stack+0x18f/0x20d [ 62.876108][ T156] ? afs_wake_up_async_call+0x680/0x770 [ 62.881650][ T156] ? afs_put_call+0xa40/0xa40 [ 62.886339][ T156] panic+0x2e3/0x75c [ 62.890238][ T156] ? __warn_printk+0xf3/0xf3 [ 62.894830][ T156] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.901006][ T156] ? trace_hardirqs_on+0x55/0x220 [ 62.906035][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.911590][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.917134][ T156] ? afs_put_call+0xa40/0xa40 [ 62.921813][ T156] end_report+0x4d/0x53 [ 62.926011][ T156] kasan_report.cold+0xd/0x37 [ 62.930770][ T156] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.936411][ T156] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.941960][ T156] afs_wake_up_async_call+0x6aa/0x770 [ 62.947326][ T156] ? afs_close_socket+0x320/0x320 [ 62.952345][ T156] ? afs_put_call+0xa40/0xa40 [ 62.957106][ T156] rxrpc_notify_socket+0x1db/0x5d0 [ 62.962334][ T156] ? afs_put_call+0xa40/0xa40 [ 62.967006][ T156] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.973416][ T156] rxrpc_call_completed+0xca/0xf0 [ 62.978551][ T156] rxrpc_discard_prealloc+0x781/0xab0 [ 62.983930][ T156] ? lock_sock_nested+0x94/0x110 [ 62.988991][ T156] rxrpc_listen+0x147/0x360 [ 62.993493][ T156] afs_close_socket+0x95/0x320 [ 62.998266][ T156] ? afs_purge_servers+0x16d/0x300 [ 63.003816][ T156] ? afs_rx_discard_new_call+0x50/0x50 [ 63.009272][ T156] ? init_wait_var_entry+0x200/0x200 [ 63.014684][ T156] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.020408][ T156] ? check_preemption_disabled+0x38/0x220 [ 63.026303][ T156] afs_net_exit+0x1bc/0x310 [ 63.030814][ T156] ? afs_net_init+0xe30/0xe30 [ 63.035493][ T156] ops_exit_list.isra.0+0xa8/0x150 [ 63.040613][ T156] cleanup_net+0x511/0xa50 [ 63.045028][ T156] ? unregister_pernet_device+0x70/0x70 [ 63.050569][ T156] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.056550][ T156] process_one_work+0x965/0x1690 [ 63.061484][ T156] ? lock_release+0x800/0x800 [ 63.066154][ T156] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.071522][ T156] ? rwlock_bug.part.0+0x90/0x90 [ 63.076482][ T156] worker_thread+0x96/0xe10 [ 63.080990][ T156] ? process_one_work+0x1690/0x1690 [ 63.086180][ T156] kthread+0x3b5/0x4a0 [ 63.090241][ T156] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.095950][ T156] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.101687][ T156] ret_from_fork+0x1f/0x30 [ 63.107645][ T156] Kernel Offset: disabled [ 63.112050][ T156] Rebooting in 86400 seconds..