[ OK ] Reached target Multi-User System. [ OK ] Reached target Graphical Interface. Starting Update UTMP about System Runlevel Changes... [ OK ] Started Load/Save RF Kill Switch Status. [ OK ] Started Update UTMP about System Runlevel Changes. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.10.43' (ECDSA) to the list of known hosts. 2020/06/25 20:20:56 fuzzer started 2020/06/25 20:20:56 connecting to host at 10.128.0.26:33259 2020/06/25 20:20:56 checking machine... 2020/06/25 20:20:56 checking revisions... 2020/06/25 20:20:56 testing simple program... syzkaller login: [ 64.176685][ T6822] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 20:20:57 building call list... [ 64.501465][ T21] tipc: TX() has been purged, node left! [ 65.033732][ T21] ================================================================== [ 65.042156][ T21] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 65.050049][ T21] Write of size 1 at addr ffff8880819fa9e4 by task kworker/u4:1/21 [ 65.057936][ T21] [ 65.060271][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Not tainted 5.8.0-rc2-syzkaller #0 [ 65.068507][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.078568][ T21] Workqueue: netns cleanup_net [ 65.083332][ T21] Call Trace: [ 65.086630][ T21] dump_stack+0x18f/0x20d [ 65.090976][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.096529][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.102160][ T21] ? afs_put_call+0x440/0x440 [ 65.106838][ T21] print_address_description.constprop.0.cold+0xae/0x436 [ 65.113869][ T21] ? vprintk_func+0x97/0x1a6 [ 65.118460][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.124001][ T21] kasan_report.cold+0x1f/0x37 [ 65.128769][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.134315][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 65.139690][ T21] ? afs_close_socket+0x320/0x320 [ 65.144714][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 65.149838][ T21] ? afs_put_call+0x440/0x440 [ 65.154540][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 65.160957][ T21] rxrpc_call_completed+0xd0/0xf0 [ 65.166003][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 65.171373][ T21] ? lock_sock_nested+0x94/0x110 [ 65.176312][ T21] rxrpc_listen+0x11c/0x330 [ 65.180826][ T21] afs_close_socket+0x95/0x320 [ 65.185584][ T21] ? afs_purge_servers+0x181/0x330 [ 65.190695][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 65.196153][ T21] ? init_wait_var_entry+0x200/0x200 [ 65.201448][ T21] afs_net_exit+0x1c4/0x310 [ 65.205963][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 65.211588][ T21] ops_exit_list+0xb0/0x160 [ 65.216093][ T21] cleanup_net+0x4ea/0xa00 [ 65.220504][ T21] ? __schedule+0x887/0x1eb0 [ 65.225096][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 65.230466][ T21] ? check_preemption_disabled+0x38/0x220 [ 65.236192][ T21] process_one_work+0x94c/0x1670 [ 65.241134][ T21] ? lock_release+0x8d0/0x8d0 [ 65.245807][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 65.251197][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 65.256151][ T21] worker_thread+0x64c/0x1120 [ 65.260852][ T21] ? process_one_work+0x1670/0x1670 [ 65.266051][ T21] kthread+0x3b5/0x4a0 [ 65.270117][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 65.275223][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 65.280352][ T21] ret_from_fork+0x1f/0x30 [ 65.284777][ T21] [ 65.287097][ T21] Allocated by task 6822: [ 65.291420][ T21] save_stack+0x1b/0x40 [ 65.295571][ T21] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 65.301197][ T21] kmem_cache_alloc_trace+0x14f/0x2d0 [ 65.306559][ T21] afs_alloc_call+0x4f/0x360 [ 65.311228][ T21] afs_charge_preallocation+0xe9/0x2d0 [ 65.316688][ T21] afs_open_socket+0x294/0x360 [ 65.321442][ T21] afs_net_init+0xab4/0xe90 [ 65.325936][ T21] ops_init+0xaf/0x470 [ 65.329995][ T21] setup_net+0x2d8/0x850 [ 65.334232][ T21] copy_net_ns+0x2cf/0x5e0 [ 65.338641][ T21] create_new_namespaces+0x3f6/0xb10 [ 65.343920][ T21] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 65.349547][ T21] ksys_unshare+0x36c/0x9a0 [ 65.354057][ T21] __ia32_sys_unshare+0x2c/0x40 [ 65.358904][ T21] do_syscall_32_irqs_on+0x3f/0x60 [ 65.364007][ T21] do_fast_syscall_32+0x7f/0x120 [ 65.368941][ T21] entry_SYSENTER_compat+0x6d/0x7c [ 65.374036][ T21] [ 65.376354][ T21] Freed by task 21: [ 65.380165][ T21] save_stack+0x1b/0x40 [ 65.384321][ T21] __kasan_slab_free+0xf5/0x140 [ 65.389162][ T21] kfree+0x103/0x2c0 [ 65.393058][ T21] afs_put_call+0x345/0x440 [ 65.397554][ T21] rxrpc_discard_prealloc+0x75a/0xab0 [ 65.402920][ T21] rxrpc_listen+0x11c/0x330 [ 65.407426][ T21] afs_close_socket+0x95/0x320 [ 65.412197][ T21] afs_net_exit+0x1c4/0x310 [ 65.416719][ T21] ops_exit_list+0xb0/0x160 [ 65.421222][ T21] cleanup_net+0x4ea/0xa00 [ 65.425632][ T21] process_one_work+0x94c/0x1670 [ 65.430562][ T21] worker_thread+0x64c/0x1120 [ 65.435233][ T21] kthread+0x3b5/0x4a0 [ 65.439297][ T21] ret_from_fork+0x1f/0x30 [ 65.443699][ T21] [ 65.446023][ T21] The buggy address belongs to the object at ffff8880819fa800 [ 65.446023][ T21] which belongs to the cache kmalloc-1k of size 1024 [ 65.460072][ T21] The buggy address is located 484 bytes inside of [ 65.460072][ T21] 1024-byte region [ffff8880819fa800, ffff8880819fac00) [ 65.473424][ T21] The buggy address belongs to the page: [ 65.479074][ T21] page:ffffea0002067e80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 65.489211][ T21] flags: 0xfffe0000000200(slab) [ 65.494061][ T21] raw: 00fffe0000000200 ffffea0002067e08 ffffea0002067ec8 ffff8880aa000c40 [ 65.502640][ T21] raw: 0000000000000000 ffff8880819fa000 0000000100000002 0000000000000000 [ 65.511208][ T21] page dumped because: kasan: bad access detected [ 65.517604][ T21] [ 65.519920][ T21] Memory state around the buggy address: [ 65.525560][ T21] ffff8880819fa880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.533617][ T21] ffff8880819fa900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.541674][ T21] >ffff8880819fa980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.549723][ T21] ^ [ 65.556919][ T21] ffff8880819faa00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.564991][ T21] ffff8880819faa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 65.573042][ T21] ================================================================== [ 65.581093][ T21] Disabling lock debugging due to kernel taint [ 65.587314][ T21] Kernel panic - not syncing: panic_on_warn set ... [ 65.594336][ T21] CPU: 1 PID: 21 Comm: kworker/u4:1 Tainted: G B 5.8.0-rc2-syzkaller #0 [ 65.603961][ T21] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 65.614022][ T21] Workqueue: netns cleanup_net [ 65.618775][ T21] Call Trace: [ 65.622064][ T21] dump_stack+0x18f/0x20d [ 65.626399][ T21] ? afs_wake_up_async_call+0x340/0x4a0 [ 65.631952][ T21] ? afs_put_call+0x440/0x440 [ 65.636626][ T21] panic+0x2e3/0x75c [ 65.640524][ T21] ? __warn_printk+0xf3/0xf3 [ 65.645134][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.650696][ T21] ? trace_hardirqs_on+0x55/0x220 [ 65.655799][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.661330][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.666864][ T21] ? afs_put_call+0x440/0x440 [ 65.671648][ T21] end_report+0x4d/0x53 [ 65.675787][ T21] kasan_report.cold+0xd/0x37 [ 65.682470][ T21] ? afs_wake_up_async_call+0x430/0x4a0 [ 65.688017][ T21] afs_wake_up_async_call+0x430/0x4a0 [ 65.693380][ T21] ? afs_close_socket+0x320/0x320 [ 65.698402][ T21] rxrpc_notify_socket+0x1db/0x5d0 [ 65.703496][ T21] ? afs_put_call+0x440/0x440 [ 65.708164][ T21] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 65.714566][ T21] rxrpc_call_completed+0xd0/0xf0 [ 65.719573][ T21] rxrpc_discard_prealloc+0x777/0xab0 [ 65.724934][ T21] ? lock_sock_nested+0x94/0x110 [ 65.730022][ T21] rxrpc_listen+0x11c/0x330 [ 65.734518][ T21] afs_close_socket+0x95/0x320 [ 65.739268][ T21] ? afs_purge_servers+0x181/0x330 [ 65.744356][ T21] ? afs_rx_discard_new_call+0x50/0x50 [ 65.749791][ T21] ? init_wait_var_entry+0x200/0x200 [ 65.755052][ T21] afs_net_exit+0x1c4/0x310 [ 65.759536][ T21] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 65.765154][ T21] ops_exit_list+0xb0/0x160 [ 65.769644][ T21] cleanup_net+0x4ea/0xa00 [ 65.774053][ T21] ? __schedule+0x887/0x1eb0 [ 65.778623][ T21] ? ops_free_list.part.0+0x3d0/0x3d0 [ 65.783981][ T21] ? check_preemption_disabled+0x38/0x220 [ 65.789768][ T21] process_one_work+0x94c/0x1670 [ 65.794778][ T21] ? lock_release+0x8d0/0x8d0 [ 65.799460][ T21] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 65.804827][ T21] ? rwlock_bug.part.0+0x90/0x90 [ 65.809758][ T21] worker_thread+0x64c/0x1120 [ 65.814422][ T21] ? process_one_work+0x1670/0x1670 [ 65.819607][ T21] kthread+0x3b5/0x4a0 [ 65.823727][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 65.828826][ T21] ? __kthread_bind_mask+0xc0/0xc0 [ 65.833920][ T21] ret_from_fork+0x1f/0x30 [ 65.839602][ T21] Kernel Offset: disabled [ 65.843915][ T21] Rebooting in 86400 seconds..