Starting Load/Save RF Kill Switch Status... [ OK ] Started Load/Save RF Kill Switch Status. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.231' (ECDSA) to the list of known hosts. 2020/06/17 05:28:21 fuzzer started 2020/06/17 05:28:21 connecting to host at 10.128.0.26:43607 2020/06/17 05:28:21 checking machine... 2020/06/17 05:28:21 checking revisions... 2020/06/17 05:28:21 testing simple program... syzkaller login: [ 61.472128][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/17 05:28:22 building call list... [ 61.767778][ T21] tipc: TX() has been purged, node left! [ 62.309670][ T21] ================================================================== [ 62.318002][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x6aa/0x770 [ 62.325888][ T21] Write of size 1 at addr ffff8880946c39e4 by task kworker/u4:1/21 [ 62.333787][ T21] [ 62.336121][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc1-syzkaller #0 [ 62.344351][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.354446][ T21] Workqueue: netns cleanup_net [ 62.359202][ T21] Call Trace: [ 62.362510][ T21] dump_stack+0x18f/0x20d [ 62.366839][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.372380][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.377919][ T21] ? afs_put_call+0xa40/0xa40 [ 62.382612][ T21] print_address_description.constprop.0.cold+0xd3/0x413 [ 62.389725][ T21] ? vprintk_func+0x97/0x1a6 [ 62.394317][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.399910][ T21] kasan_report.cold+0x1f/0x37 [ 62.404999][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.410894][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.418741][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 62.424283][ T21] ? afs_close_socket+0x320/0x320 [ 62.429309][ T21] ? afs_put_call+0xa40/0xa40 [ 62.433990][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 62.439370][ T21] ? afs_put_call+0xa40/0xa40 [ 62.444339][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 62.451118][ T21] rxrpc_call_completed+0xca/0xf0 [ 62.457541][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 62.463097][ T21] ? lock_sock_nested+0x94/0x110 [ 62.468391][ T21] rxrpc_listen+0x147/0x360 [ 62.472958][ T21] afs_close_socket+0x95/0x320 [ 62.477741][ T21] ? afs_purge_servers+0x16d/0x300 [ 62.482949][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 62.488435][ T21] ? init_wait_var_entry+0x200/0x200 [ 62.495074][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 62.501237][ T21] ? check_preemption_disabled+0x38/0x220 [ 62.507617][ T21] afs_net_exit+0x1bc/0x310 [ 62.512215][ T21] ? afs_net_init+0xe30/0xe30 [ 62.517966][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.523811][ T21] cleanup_net+0x511/0xa50 [ 62.528345][ T21] ? unregister_pernet_device+0x70/0x70 [ 62.535290][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 62.542426][ T21] process_one_work+0x965/0x1690 [ 62.547794][ T21] ? lock_release+0x800/0x800 [ 62.552575][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 62.557950][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 62.562901][ T21] worker_thread+0x96/0xe10 [ 62.568137][ T21] ? process_one_work+0x1690/0x1690 [ 62.573510][ T21] kthread+0x3b5/0x4a0 [ 62.577632][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.583800][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 62.589701][ T21] ret_from_fork+0x1f/0x30 [ 62.594229][ T21] [ 62.596735][ T21] Allocated by task 6820: [ 62.601154][ T21] save_stack+0x1b/0x40 [ 62.605630][ T21] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 62.611350][ T21] kmem_cache_alloc_trace+0x153/0x7d0 [ 62.616718][ T21] afs_alloc_call+0x55/0x630 [ 62.621341][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 62.627938][ T21] afs_open_socket+0x292/0x360 [ 62.633075][ T21] afs_net_init+0xa6c/0xe30 [ 62.637579][ T21] ops_init+0xaf/0x420 [ 62.641649][ T21] setup_net+0x2de/0x860 [ 62.645887][ T21] copy_net_ns+0x293/0x590 [ 62.650315][ T21] create_new_namespaces+0x3fb/0xb30 [ 62.655785][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 62.663168][ T21] ksys_unshare+0x43d/0x8e0 [ 62.667678][ T21] __x64_sys_unshare+0x2d/0x40 [ 62.672441][ T21] do_syscall_64+0x60/0xe0 [ 62.676859][ T21] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 62.682764][ T21] [ 62.685089][ T21] Freed by task 21: [ 62.689253][ T21] save_stack+0x1b/0x40 [ 62.693750][ T21] __kasan_slab_free+0xf7/0x140 [ 62.698609][ T21] kfree+0x109/0x2b0 [ 62.702606][ T21] afs_put_call+0x585/0xa40 [ 62.707112][ T21] rxrpc_discard_prealloc+0x764/0xab0 [ 62.712506][ T21] rxrpc_listen+0x147/0x360 [ 62.717015][ T21] afs_close_socket+0x95/0x320 [ 62.721861][ T21] afs_net_exit+0x1bc/0x310 [ 62.726360][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 62.731470][ T21] cleanup_net+0x511/0xa50 [ 62.735883][ T21] process_one_work+0x965/0x1690 [ 62.740826][ T21] worker_thread+0x96/0xe10 [ 62.745322][ T21] kthread+0x3b5/0x4a0 [ 62.749397][ T21] ret_from_fork+0x1f/0x30 [ 62.753825][ T21] [ 62.756153][ T21] The buggy address belongs to the object at ffff8880946c3800 [ 62.756153][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 62.770733][ T21] The buggy address is located 484 bytes inside of [ 62.770733][ T21] 1024-byte region [ffff8880946c3800, ffff8880946c3c00) [ 62.784086][ T21] The buggy address belongs to the page: [ 62.789999][ T21] page:ffffea000251b0c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 62.799126][ T21] flags: 0xfffe0000000200(slab) [ 62.804014][ T21] raw: 00fffe0000000200 ffffea0002546508 ffffea00024fa248 ffff8880aa000c40 [ 62.812609][ T21] raw: 0000000000000000 ffff8880946c3000 0000000100000002 0000000000000000 [ 62.821448][ T21] page dumped because: kasan: bad access detected [ 62.827883][ T21] [ 62.830211][ T21] Memory state around the buggy address: [ 62.835854][ T21] ffff8880946c3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.843928][ T21] ffff8880946c3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.852000][ T21] >ffff8880946c3980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.860057][ T21] ^ [ 62.867251][ T21] ffff8880946c3a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.875333][ T21] ffff8880946c3a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 62.883385][ T21] ================================================================== [ 62.891724][ T21] Disabling lock debugging due to kernel taint [ 62.897936][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 62.904533][ T21] CPU: 0 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 62.914154][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 62.924218][ T21] Workqueue: netns cleanup_net [ 62.928974][ T21] Call Trace: [ 62.932260][ T21] dump_stack+0x18f/0x20d [ 62.936669][ T21] ? afs_wake_up_async_call+0x670/0x770 [ 62.942374][ T21] ? afs_put_call+0xa40/0xa40 [ 62.947044][ T21] panic+0x2e3/0x75c [ 62.950938][ T21] ? __warn_printk+0xf3/0xf3 [ 62.955562][ T21] ? asm_sysvec_apic_timer_interrupt+0x12/0x20 [ 62.961724][ T21] ? trace_hardirqs_on+0x55/0x220 [ 62.966756][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.972302][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 62.977835][ T21] ? afs_put_call+0xa40/0xa40 [ 62.982525][ T21] end_report+0x4d/0x53 [ 62.986765][ T21] kasan_report.cold+0xd/0x37 [ 62.991439][ T21] ? rcu_read_lock_held_common+0x51/0xa0 [ 62.997078][ T21] ? afs_wake_up_async_call+0x6aa/0x770 [ 63.002614][ T21] afs_wake_up_async_call+0x6aa/0x770 [ 63.007977][ T21] ? afs_close_socket+0x320/0x320 [ 63.013011][ T21] ? afs_put_call+0xa40/0xa40 [ 63.017699][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 63.022825][ T21] ? afs_put_call+0xa40/0xa40 [ 63.027497][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 63.033905][ T21] rxrpc_call_completed+0xca/0xf0 [ 63.038927][ T21] rxrpc_discard_prealloc+0x781/0xab0 [ 63.044317][ T21] ? lock_sock_nested+0x94/0x110 [ 63.049363][ T21] rxrpc_listen+0x147/0x360 [ 63.053864][ T21] afs_close_socket+0x95/0x320 [ 63.058622][ T21] ? afs_purge_servers+0x16d/0x300 [ 63.063727][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 63.069180][ T21] ? init_wait_var_entry+0x200/0x200 [ 63.074458][ T21] ? rcu_read_lock_held_common+0xa0/0xa0 [ 63.080088][ T21] ? check_preemption_disabled+0x38/0x220 [ 63.085820][ T21] afs_net_exit+0x1bc/0x310 [ 63.090328][ T21] ? afs_net_init+0xe30/0xe30 [ 63.094995][ T21] ops_exit_list.isra.0+0xa8/0x150 [ 63.100099][ T21] cleanup_net+0x511/0xa50 [ 63.104508][ T21] ? unregister_pernet_device+0x70/0x70 [ 63.110051][ T21] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 63.116058][ T21] process_one_work+0x965/0x1690 [ 63.120993][ T21] ? lock_release+0x800/0x800 [ 63.125664][ T21] ? pwq_dec_nr_in_flight+0x310/0x310 [ 63.131026][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 63.135960][ T21] worker_thread+0x96/0xe10 [ 63.140460][ T21] ? process_one_work+0x1690/0x1690 [ 63.145653][ T21] kthread+0x3b5/0x4a0 [ 63.149715][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.155448][ T21] ? kthread_mod_delayed_work+0x1a0/0x1a0 [ 63.161163][ T21] ret_from_fork+0x1f/0x30 [ 63.167042][ T21] Kernel Offset: disabled [ 63.171485][ T21] Rebooting in 86400 seconds..