[ 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 '10.128.10.40' (ECDSA) to the list of known hosts. 2020/06/14 21:43:32 fuzzer started 2020/06/14 21:43:32 connecting to host at 10.128.0.26:38225 2020/06/14 21:43:32 checking machine... 2020/06/14 21:43:32 checking revisions... 2020/06/14 21:43:32 testing simple program... syzkaller login: [ 60.850691][ T6837] IPVS: ftp: loaded support on port[0] = 21 2020/06/14 21:43:33 building call list... [ 61.255737][ T82] tipc: TX() has been purged, node left! [ 61.758543][ T82] ================================================================== [ 61.766944][ T82] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 61.774835][ T82] Write of size 1 at addr ffff88809345f9e4 by task kworker/u4:3/82 [ 61.782726][ T82] [ 61.785080][ T82] CPU: 1 PID: 82 Comm: kworker/u4:3 Not tainted 5.7.0-next-20200614-syzkaller #0 [ 61.794263][ T82] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 61.804758][ T82] Workqueue: netns cleanup_net [ 61.809688][ T82] Call Trace: [ 61.812990][ T82] dump_stack+0x18f/0x20d [ 61.817667][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.823209][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.832869][ T82] ? afs_put_call+0xa40/0xa40 [ 61.838283][ T82] print_address_description.constprop.0.cold+0xd3/0x413 [ 61.845317][ T82] ? vprintk_func+0x97/0x1a6 [ 61.849946][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.855682][ T82] kasan_report.cold+0x1f/0x37 [ 61.860741][ T82] ? rcu_read_lock_held_common+0x41/0xa0 [ 61.866377][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 61.871931][ T82] afs_wake_up_async_call+0x6aa/0x770 [ 61.877302][ T82] ? afs_close_socket+0x320/0x320 [ 61.882326][ T82] ? afs_put_call+0xa40/0xa40 [ 61.887176][ T82] rxrpc_notify_socket+0x1db/0x5d0 [ 61.892292][ T82] ? afs_put_call+0xa40/0xa40 [ 61.896965][ T82] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 61.903381][ T82] rxrpc_call_completed+0xca/0xf0 [ 61.908405][ T82] rxrpc_discard_prealloc+0x781/0xab0 [ 61.914517][ T82] ? lock_sock_nested+0x94/0x110 [ 61.919458][ T82] rxrpc_listen+0x147/0x360 [ 61.923963][ T82] afs_close_socket+0x95/0x320 [ 61.928821][ T82] ? afs_purge_servers+0x16d/0x300 [ 61.933934][ T82] ? afs_rx_discard_new_call+0x50/0x50 [ 61.939395][ T82] ? init_wait_var_entry+0x200/0x200 [ 61.944680][ T82] ? rcu_read_lock_held_common+0xa0/0xa0 [ 61.950317][ T82] ? check_preemption_disabled+0x38/0x220 [ 61.956062][ T82] afs_net_exit+0x1bc/0x310 [ 61.960565][ T82] ? afs_net_init+0xe30/0xe30 [ 61.965248][ T82] ops_exit_list.isra.0+0xa8/0x150 [ 61.970565][ T82] cleanup_net+0x511/0xa50 [ 61.975885][ T82] ? unregister_pernet_device+0x70/0x70 [ 61.981487][ T82] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 61.987488][ T82] process_one_work+0x965/0x1690 [ 61.992554][ T82] ? lock_release+0x800/0x800 [ 61.997234][ T82] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.002871][ T82] ? rwlock_bug.part.0+0x90/0x90 [ 62.007834][ T82] worker_thread+0x96/0xe10 [ 62.012384][ T82] ? process_one_work+0x1690/0x1690 [ 62.020900][ T82] kthread+0x3b5/0x4a0 [ 62.024981][ T82] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.031002][ T82] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.036815][ T82] ret_from_fork+0x1f/0x30 [ 62.041278][ T82] [ 62.043691][ T82] Allocated by task 6837: [ 62.048205][ T82] save_stack+0x1b/0x40 [ 62.052368][ T82] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.057997][ T82] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.063534][ T82] afs_alloc_call+0x55/0x630 [ 62.068121][ T82] afs_charge_preallocation+0xe9/0x2d0 [ 62.073579][ T82] afs_open_socket+0x292/0x360 [ 62.078426][ T82] afs_net_init+0xa6c/0xe30 [ 62.083012][ T82] ops_init+0xaf/0x420 [ 62.087252][ T82] setup_net+0x2de/0x860 [ 62.091489][ T82] copy_net_ns+0x293/0x590 [ 62.095911][ T82] create_new_namespaces+0x3fb/0xb30 [ 62.101570][ T82] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.107210][ T82] ksys_unshare+0x43d/0x8e0 [ 62.111713][ T82] __x64_sys_unshare+0x2d/0x40 [ 62.116475][ T82] do_syscall_64+0x60/0xe0 [ 62.120888][ T82] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.126778][ T82] [ 62.129114][ T82] Freed by task 82: [ 62.132943][ T82] save_stack+0x1b/0x40 [ 62.137132][ T82] __kasan_slab_free+0xf7/0x140 [ 62.142142][ T82] kfree+0x109/0x2b0 [ 62.146064][ T82] afs_put_call+0x585/0xa40 [ 62.150576][ T82] rxrpc_discard_prealloc+0x764/0xab0 [ 62.155964][ T82] rxrpc_listen+0x147/0x360 [ 62.160732][ T82] afs_close_socket+0x95/0x320 [ 62.165617][ T82] afs_net_exit+0x1bc/0x310 [ 62.170332][ T82] ops_exit_list.isra.0+0xa8/0x150 [ 62.175919][ T82] cleanup_net+0x511/0xa50 [ 62.181247][ T82] process_one_work+0x965/0x1690 [ 62.186612][ T82] worker_thread+0x96/0xe10 [ 62.191328][ T82] kthread+0x3b5/0x4a0 [ 62.195408][ T82] ret_from_fork+0x1f/0x30 [ 62.200978][ T82] [ 62.203663][ T82] The buggy address belongs to the object at ffff88809345f800 [ 62.203663][ T82] which belongs to the cache kmalloc-1k of size 1024 [ 62.217920][ T82] The buggy address is located 484 bytes inside of [ 62.217920][ T82] 1024-byte region [ffff88809345f800, ffff88809345fc00) [ 62.231471][ T82] The buggy address belongs to the page: [ 62.237119][ T82] page:ffffea00024d17c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.247264][ T82] flags: 0xfffe0000000200(slab) [ 62.252958][ T82] raw: 00fffe0000000200 ffffea00024ff748 ffffea0002869988 ffff8880aa000c40 [ 62.261895][ T82] raw: 0000000000000000 ffff88809345f000 0000000100000002 0000000000000000 [ 62.275533][ T82] page dumped because: kasan: bad access detected [ 62.282116][ T82] [ 62.284446][ T82] Memory state around the buggy address: [ 62.290995][ T82] ffff88809345f880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.299162][ T82] ffff88809345f900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.307227][ T82] >ffff88809345f980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.316003][ T82] ^ [ 62.323559][ T82] ffff88809345fa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.331800][ T82] ffff88809345fa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.340216][ T82] ================================================================== [ 62.355677][ T82] Disabling lock debugging due to kernel taint [ 62.361890][ T82] Kernel panic - not syncing: panic_on_warn set ... [ 62.369292][ T82] CPU: 1 PID: 82 Comm: kworker/u4:3 Tainted: G B 5.7.0-next-20200614-syzkaller #0 [ 62.379780][ T82] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.389856][ T82] Workqueue: netns cleanup_net [ 62.394603][ T82] Call Trace: [ 62.397895][ T82] dump_stack+0x18f/0x20d [ 62.402318][ T82] ? afs_wake_up_async_call+0x5e0/0x770 [ 62.407865][ T82] ? afs_put_call+0xa40/0xa40 [ 62.412532][ T82] panic+0x2e3/0x75c [ 62.418001][ T82] ? __warn_printk+0xf3/0xf3 [ 62.423478][ T82] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.431125][ T82] ? trace_hardirqs_on+0x55/0x220 [ 62.436428][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.442608][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.457009][ T82] ? afs_put_call+0xa40/0xa40 [ 62.461687][ T82] end_report+0x4d/0x53 [ 62.465848][ T82] kasan_report.cold+0xd/0x37 [ 62.470645][ T82] ? rcu_read_lock_held_common+0x41/0xa0 [ 62.476271][ T82] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.481899][ T82] afs_wake_up_async_call+0x6aa/0x770 [ 62.496385][ T82] ? afs_close_socket+0x320/0x320 [ 62.515156][ T82] ? afs_put_call+0xa40/0xa40 [ 62.537895][ T82] rxrpc_notify_socket+0x1db/0x5d0 [ 62.543007][ T82] ? afs_put_call+0xa40/0xa40 [ 62.547678][ T82] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.554083][ T82] rxrpc_call_completed+0xca/0xf0 [ 62.559117][ T82] rxrpc_discard_prealloc+0x781/0xab0 [ 62.564492][ T82] ? lock_sock_nested+0x94/0x110 [ 62.569425][ T82] rxrpc_listen+0x147/0x360 [ 62.573940][ T82] afs_close_socket+0x95/0x320 [ 62.578693][ T82] ? afs_purge_servers+0x16d/0x300 [ 62.583804][ T82] ? afs_rx_discard_new_call+0x50/0x50 [ 62.589437][ T82] ? init_wait_var_entry+0x200/0x200 [ 62.594716][ T82] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.600337][ T82] ? check_preemption_disabled+0x38/0x220 [ 62.606654][ T82] afs_net_exit+0x1bc/0x310 [ 62.611343][ T82] ? afs_net_init+0xe30/0xe30 [ 62.616011][ T82] ops_exit_list.isra.0+0xa8/0x150 [ 62.621201][ T82] cleanup_net+0x511/0xa50 [ 62.625631][ T82] ? unregister_pernet_device+0x70/0x70 [ 62.631173][ T82] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.638376][ T82] process_one_work+0x965/0x1690 [ 62.643322][ T82] ? lock_release+0x800/0x800 [ 62.648109][ T82] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.654271][ T82] ? rwlock_bug.part.0+0x90/0x90 [ 62.659225][ T82] worker_thread+0x96/0xe10 [ 62.664606][ T82] ? process_one_work+0x1690/0x1690 [ 62.670063][ T82] kthread+0x3b5/0x4a0 [ 62.674125][ T82] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.679837][ T82] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.685555][ T82] ret_from_fork+0x1f/0x30 [ 62.691417][ T82] Kernel Offset: disabled [ 62.695924][ T82] Rebooting in 86400 seconds..