[ 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... Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.1.51' (ECDSA) to the list of known hosts. 2020/06/19 08:55:49 fuzzer started 2020/06/19 08:55:50 connecting to host at 10.128.0.26:33143 2020/06/19 08:55:50 checking machine... 2020/06/19 08:55:50 checking revisions... 2020/06/19 08:55:50 testing simple program... syzkaller login: [ 63.709536][ T6821] IPVS: ftp: loaded support on port[0] = 21 2020/06/19 08:55:50 building call list... [ 64.037144][ T21] tipc: TX() has been purged, node left! [ 64.559306][ T21] ================================================================== [ 64.567558][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 64.575531][ T21] Write of size 1 at addr ffff8880930919e4 by task kworker/u4:1/21 [ 64.583409][ T21] [ 64.585915][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 64.594227][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 64.604281][ T21] Workqueue: netns cleanup_net [ 64.609210][ T21] Call Trace: [ 64.612511][ T21] dump_stack+0x18f/0x20d [ 64.616855][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.622394][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.627941][ T21] ? afs_put_call+0xa40/0xa40 [ 64.632627][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 64.639674][ T21] ? vprintk_func+0x97/0x1a6 [ 64.644373][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.649921][ T21] kasan_report.cold+0x1f/0x37 [ 64.654712][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 64.660384][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 64.665950][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 64.671338][ T21] ? afs_close_socket+0x320/0x320 [ 64.676384][ T21] ? afs_put_call+0xa40/0xa40 [ 64.681067][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 64.686190][ T21] ? afs_put_call+0xa40/0xa40 [ 64.690870][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 64.697299][ T21] rxrpc_call_completed+0xca/0xf0 [ 64.702351][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 64.707736][ T21] ? lock_sock_nested+0x94/0x110 [ 64.712685][ T21] rxrpc_listen+0x147/0x360 [ 64.717209][ T21] afs_close_socket+0x95/0x320 [ 64.721977][ T21] ? afs_purge_servers+0x16d/0x300 [ 64.727104][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 64.732585][ T21] ? init_wait_var_entry+0x200/0x200 [ 64.737876][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 64.743524][ T21] ? check_preemption_disabled+0x38/0x220 [ 64.749255][ T21] afs_net_exit+0x1bc/0x310 [ 64.753859][ T21] ? afs_net_init+0xe30/0xe30 [ 64.758548][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 64.763662][ T21] cleanup_net+0x511/0xa50 [ 64.768113][ T21] ? unregister_pernet_device+0x70/0x70 [ 64.773682][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 64.779673][ T21] process_one_work+0x965/0x1690 [ 64.784637][ T21] ? lock_release+0x800/0x800 [ 64.789332][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 64.794715][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 64.799672][ T21] worker_thread+0x96/0xe10 [ 64.804220][ T21] ? process_one_work+0x1690/0x1690 [ 64.809584][ T21] kthread+0x3b5/0x4a0 [ 64.813656][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.819389][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 64.825118][ T21] ret_from_fork+0x1f/0x30 [ 64.829548][ T21] [ 64.831871][ T21] Allocated by task 6821: [ 64.836216][ T21] save_stack+0x1b/0x40 [ 64.840370][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 64.845997][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 64.851366][ T21] afs_alloc_call+0x55/0x630 [ 64.855955][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 64.861429][ T21] afs_open_socket+0x292/0x360 [ 64.866196][ T21] afs_net_init+0xa6c/0xe30 [ 64.870711][ T21] ops_init+0xaf/0x420 [ 64.874782][ T21] setup_net+0x2de/0x860 [ 64.879040][ T21] copy_net_ns+0x293/0x590 [ 64.883454][ T21] create_new_namespaces+0x3fb/0xb30 [ 64.888839][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 64.894481][ T21] ksys_unshare+0x43d/0x8e0 [ 64.898990][ T21] __x64_sys_unshare+0x2d/0x40 [ 64.903752][ T21] do_syscall_64+0x60/0xe0 [ 64.908170][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 64.914056][ T21] [ 64.916382][ T21] Freed by task 21: [ 64.920193][ T21] save_stack+0x1b/0x40 [ 64.924348][ T21] __kasan_slab_free+0xf7/0x140 [ 64.929193][ T21] kfree+0x109/0x2b0 [ 64.933083][ T21] afs_put_call+0x585/0xa40 [ 64.937586][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 64.942960][ T21] rxrpc_listen+0x147/0x360 [ 64.947890][ T21] afs_close_socket+0x95/0x320 [ 64.952646][ T21] afs_net_exit+0x1bc/0x310 [ 64.957148][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 64.962967][ T21] cleanup_net+0x511/0xa50 [ 64.967468][ T21] process_one_work+0x965/0x1690 [ 64.972408][ T21] worker_thread+0x96/0xe10 [ 64.976909][ T21] kthread+0x3b5/0x4a0 [ 64.980985][ T21] ret_from_fork+0x1f/0x30 [ 64.985392][ T21] [ 64.987719][ T21] The buggy address belongs to the object at ffff888093091800 [ 64.987719][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 65.001908][ T21] The buggy address is located 484 bytes inside of [ 65.001908][ T21] 1024-byte region [ffff888093091800, ffff888093091c00) [ 65.015269][ T21] The buggy address belongs to the page: [ 65.020910][ T21] page:ffffea00024c2440 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 65.030026][ T21] flags: 0xfffe0000000200(slab) [ 65.034889][ T21] raw: 00fffe0000000200 ffffea0002a43fc8 ffffea00029cd208 ffff8880aa000c40 [ 65.044793][ T21] raw: 0000000000000000 ffff888093091000 0000000100000002 0000000000000000 [ 65.053390][ T21] page dumped because: kasan: bad access detected [ 65.059939][ T21] [ 65.062281][ T21] Memory state around the buggy address: [ 65.068168][ T21] ffff888093091880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.076618][ T21] ffff888093091900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.084791][ T21] >ffff888093091980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.092862][ T21] ^ [ 65.100292][ T21] ffff888093091a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.108456][ T21] ffff888093091a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.116526][ T21] ================================================================== [ 65.124593][ T21] Disabling lock debugging due to kernel taint [ 65.130786][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 65.137371][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 65.146990][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.157481][ T21] Workqueue: netns cleanup_net [ 65.162251][ T21] Call Trace: [ 65.165544][ T21] dump_stack+0x18f/0x20d [ 65.169880][ T21] ? afs_wake_up_async_call+0x680/0x770 [ 65.175430][ T21] ? afs_put_call+0xa40/0xa40 [ 65.180121][ T21] panic+0x2e3/0x75c [ 65.184019][ T21] ? __warn_printk+0xf3/0xf3 [ 65.188614][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 65.194904][ T21] ? trace_hardirqs_on+0x55/0x220 [ 65.199939][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.205487][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.211036][ T21] ? afs_put_call+0xa40/0xa40 [ 65.215738][ T21] end_report+0x4d/0x53 [ 65.219897][ T21] kasan_report.cold+0xd/0x37 [ 65.224682][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 65.230311][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 65.235852][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 65.241264][ T21] ? afs_close_socket+0x320/0x320 [ 65.246297][ T21] ? afs_put_call+0xa40/0xa40 [ 65.251011][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 65.256117][ T21] ? afs_put_call+0xa40/0xa40 [ 65.260791][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 65.267216][ T21] rxrpc_call_completed+0xca/0xf0 [ 65.272247][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 65.277620][ T21] ? lock_sock_nested+0x94/0x110 [ 65.282577][ T21] rxrpc_listen+0x147/0x360 [ 65.287092][ T21] afs_close_socket+0x95/0x320 [ 65.291909][ T21] ? afs_purge_servers+0x16d/0x300 [ 65.297020][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 65.302483][ T21] ? init_wait_var_entry+0x200/0x200 [ 65.307773][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 65.313396][ T21] ? check_preemption_disabled+0x38/0x220 [ 65.319225][ T21] afs_net_exit+0x1bc/0x310 [ 65.323734][ T21] ? afs_net_init+0xe30/0xe30 [ 65.328402][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 65.334113][ T21] cleanup_net+0x511/0xa50 [ 65.338522][ T21] ? unregister_pernet_device+0x70/0x70 [ 65.344075][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 65.350119][ T21] process_one_work+0x965/0x1690 [ 65.355174][ T21] ? lock_release+0x800/0x800 [ 65.359852][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 65.365218][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 65.370156][ T21] worker_thread+0x96/0xe10 [ 65.374659][ T21] ? process_one_work+0x1690/0x1690 [ 65.379855][ T21] kthread+0x3b5/0x4a0 [ 65.383921][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.389643][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 65.395363][ T21] ret_from_fork+0x1f/0x30 [ 65.401087][ T21] Kernel Offset: disabled [ 65.405438][ T21] Rebooting in 86400 seconds..