[ 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. Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.15.213' (ECDSA) to the list of known hosts. 2020/06/25 15:06:42 fuzzer started 2020/06/25 15:06:42 connecting to host at 10.128.0.26:42799 2020/06/25 15:06:42 checking machine... 2020/06/25 15:06:42 checking revisions... 2020/06/25 15:06:43 testing simple program... syzkaller login: [ 59.370856][ T6820] IPVS: ftp: loaded support on port[0] = 21 2020/06/25 15:06:43 building call list... [ 59.688807][ T596] tipc: TX() has been purged, node left! [ 60.230981][ T596] ================================================================== [ 60.239210][ T596] BUG: KASAN: use-after-free in afs_wake_up_async_call+0x430/0x4a0 [ 60.247120][ T596] Write of size 1 at addr ffff8880a6b019e4 by task kworker/u4:5/596 [ 60.255078][ T596] [ 60.257405][ T596] CPU: 1 PID: 596 Comm: kworker/u4:5 Not tainted 5.8.0-rc1-syzkaller #0 [ 60.265717][ T596] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.275775][ T596] Workqueue: netns cleanup_net [ 60.280527][ T596] Call Trace: [ 60.283818][ T596] dump_stack+0x18f/0x20d [ 60.288148][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.293773][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.299312][ T596] ? afs_put_call+0x440/0x440 [ 60.304004][ T596] print_address_description.constprop.0.cold+0xae/0x436 [ 60.311217][ T596] ? vprintk_func+0x97/0x1a6 [ 60.315810][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.321351][ T596] kasan_report.cold+0x1f/0x37 [ 60.326115][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.331674][ T596] afs_wake_up_async_call+0x430/0x4a0 [ 60.337057][ T596] ? afs_close_socket+0x320/0x320 [ 60.342091][ T596] rxrpc_notify_socket+0x1db/0x5d0 [ 60.347333][ T596] ? afs_put_call+0x440/0x440 [ 60.352014][ T596] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.358440][ T596] rxrpc_call_completed+0xd0/0xf0 [ 60.363467][ T596] rxrpc_discard_prealloc+0x777/0xab0 [ 60.368841][ T596] ? lock_sock_nested+0x94/0x110 [ 60.373780][ T596] rxrpc_listen+0x11c/0x330 [ 60.378283][ T596] afs_close_socket+0x95/0x320 [ 60.383039][ T596] ? afs_purge_servers+0x16d/0x300 [ 60.388150][ T596] ? afs_rx_discard_new_call+0x50/0x50 [ 60.393618][ T596] ? init_wait_var_entry+0x200/0x200 [ 60.398904][ T596] ? check_preemption_disabled+0x38/0x220 [ 60.404625][ T596] afs_net_exit+0x1bc/0x310 [ 60.409124][ T596] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 60.414750][ T596] ops_exit_list+0xb0/0x160 [ 60.419258][ T596] cleanup_net+0x4ea/0xa00 [ 60.423667][ T596] ? __schedule+0x887/0x1eb0 [ 60.428256][ T596] ? ops_free_list.part.0+0x3d0/0x3d0 [ 60.433629][ T596] ? check_preemption_disabled+0x38/0x220 [ 60.439352][ T596] process_one_work+0x94c/0x1670 [ 60.444294][ T596] ? lock_release+0x8d0/0x8d0 [ 60.448967][ T596] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 60.454341][ T596] ? rwlock_bug.part.0+0x90/0x90 [ 60.459289][ T596] worker_thread+0x64c/0x1120 [ 60.463973][ T596] ? __kthread_parkme+0x13f/0x1e0 [ 60.468993][ T596] ? process_one_work+0x1670/0x1670 [ 60.474187][ T596] kthread+0x3b5/0x4a0 [ 60.478258][ T596] ? __kthread_bind_mask+0xc0/0xc0 [ 60.483361][ T596] ? __kthread_bind_mask+0xc0/0xc0 [ 60.488470][ T596] ret_from_fork+0x1f/0x30 [ 60.492902][ T596] [ 60.495224][ T596] Allocated by task 6820: [ 60.499552][ T596] save_stack+0x1b/0x40 [ 60.503703][ T596] __kasan_kmalloc.constprop.0+0xc2/0xd0 [ 60.509549][ T596] kmem_cache_alloc_trace+0x14f/0x2d0 [ 60.514919][ T596] afs_alloc_call+0x4f/0x360 [ 60.519508][ T596] afs_charge_preallocation+0xe9/0x2d0 [ 60.524961][ T596] afs_open_socket+0x294/0x360 [ 60.529718][ T596] afs_net_init+0xa6c/0xe30 [ 60.534224][ T596] ops_init+0xaf/0x470 [ 60.538289][ T596] setup_net+0x2d8/0x850 [ 60.542537][ T596] copy_net_ns+0x2cf/0x5e0 [ 60.546953][ T596] create_new_namespaces+0x3f6/0xb10 [ 60.552231][ T596] unshare_nsproxy_namespaces+0xbd/0x1f0 [ 60.560895][ T596] ksys_unshare+0x36c/0x9a0 [ 60.565424][ T596] __x64_sys_unshare+0x2d/0x40 [ 60.570181][ T596] do_syscall_64+0x60/0xe0 [ 60.574593][ T596] entry_SYSCALL_64_after_hwframe+0x44/0xa9 [ 60.580470][ T596] [ 60.582789][ T596] Freed by task 596: [ 60.586677][ T596] save_stack+0x1b/0x40 [ 60.590829][ T596] __kasan_slab_free+0xf5/0x140 [ 60.595673][ T596] kfree+0x103/0x2c0 [ 60.599565][ T596] afs_put_call+0x345/0x440 [ 60.604064][ T596] rxrpc_discard_prealloc+0x75a/0xab0 [ 60.610229][ T596] rxrpc_listen+0x11c/0x330 [ 60.614734][ T596] afs_close_socket+0x95/0x320 [ 60.619491][ T596] afs_net_exit+0x1bc/0x310 [ 60.623988][ T596] ops_exit_list+0xb0/0x160 [ 60.628482][ T596] cleanup_net+0x4ea/0xa00 [ 60.632891][ T596] process_one_work+0x94c/0x1670 [ 60.637821][ T596] worker_thread+0x64c/0x1120 [ 60.642489][ T596] kthread+0x3b5/0x4a0 [ 60.646555][ T596] ret_from_fork+0x1f/0x30 [ 60.650957][ T596] [ 60.653282][ T596] The buggy address belongs to the object at ffff8880a6b01800 [ 60.653282][ T596] which belongs to the cache kmalloc-1k of size 1024 [ 60.667328][ T596] The buggy address is located 484 bytes inside of [ 60.667328][ T596] 1024-byte region [ffff8880a6b01800, ffff8880a6b01c00) [ 60.680679][ T596] The buggy address belongs to the page: [ 60.686325][ T596] page:ffffea00029ac040 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 60.695429][ T596] flags: 0xfffe0000000200(slab) [ 60.700294][ T596] raw: 00fffe0000000200 ffffea0002444908 ffffea0002a2e988 ffff8880aa000c40 [ 60.708890][ T596] raw: 0000000000000000 ffff8880a6b01000 0000000100000002 0000000000000000 [ 60.717547][ T596] page dumped because: kasan: bad access detected [ 60.723951][ T596] [ 60.726268][ T596] Memory state around the buggy address: [ 60.731894][ T596] ffff8880a6b01880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.739950][ T596] ffff8880a6b01900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.748007][ T596] >ffff8880a6b01980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.756059][ T596] ^ [ 60.763679][ T596] ffff8880a6b01a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.771740][ T596] ffff8880a6b01a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 60.779789][ T596] ================================================================== [ 60.787837][ T596] Disabling lock debugging due to kernel taint [ 60.794034][ T596] Kernel panic - not syncing: panic_on_warn set ... [ 60.800615][ T596] CPU: 1 PID: 596 Comm: kworker/u4:5 Tainted: G B 5.8.0-rc1-syzkaller #0 [ 60.810317][ T596] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 60.820545][ T596] Workqueue: netns cleanup_net [ 60.825302][ T596] Call Trace: [ 60.828587][ T596] dump_stack+0x18f/0x20d [ 60.832914][ T596] ? afs_wake_up_async_call+0x3d0/0x4a0 [ 60.838451][ T596] ? afs_put_call+0x440/0x440 [ 60.843122][ T596] panic+0x2e3/0x75c [ 60.847015][ T596] ? __warn_printk+0xf3/0xf3 [ 60.851597][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.857139][ T596] ? trace_hardirqs_on+0x55/0x220 [ 60.862156][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.867692][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.873222][ T596] ? afs_put_call+0x440/0x440 [ 60.877889][ T596] end_report+0x4d/0x53 [ 60.882034][ T596] kasan_report.cold+0xd/0x37 [ 60.886709][ T596] ? afs_wake_up_async_call+0x430/0x4a0 [ 60.892244][ T596] afs_wake_up_async_call+0x430/0x4a0 [ 60.897605][ T596] ? afs_close_socket+0x320/0x320 [ 60.902728][ T596] rxrpc_notify_socket+0x1db/0x5d0 [ 60.908612][ T596] ? afs_put_call+0x440/0x440 [ 60.913281][ T596] __rxrpc_set_call_completion.part.0+0x172/0x410 [ 60.919694][ T596] rxrpc_call_completed+0xd0/0xf0 [ 60.924710][ T596] rxrpc_discard_prealloc+0x777/0xab0 [ 60.930073][ T596] ? lock_sock_nested+0x94/0x110 [ 60.935001][ T596] rxrpc_listen+0x11c/0x330 [ 60.939496][ T596] afs_close_socket+0x95/0x320 [ 60.944248][ T596] ? afs_purge_servers+0x16d/0x300 [ 60.949349][ T596] ? afs_rx_discard_new_call+0x50/0x50 [ 60.954797][ T596] ? init_wait_var_entry+0x200/0x200 [ 60.960076][ T596] ? check_preemption_disabled+0x38/0x220 [ 60.965782][ T596] afs_net_exit+0x1bc/0x310 [ 60.970274][ T596] ? __bpf_trace_afs_cb_miss+0x100/0x100 [ 60.975894][ T596] ops_exit_list+0xb0/0x160 [ 60.980390][ T596] cleanup_net+0x4ea/0xa00 [ 60.984796][ T596] ? __schedule+0x887/0x1eb0 [ 60.989375][ T596] ? ops_free_list.part.0+0x3d0/0x3d0 [ 60.994737][ T596] ? check_preemption_disabled+0x38/0x220 [ 61.000452][ T596] process_one_work+0x94c/0x1670 [ 61.005385][ T596] ? lock_release+0x8d0/0x8d0 [ 61.010053][ T596] ? pwq_dec_nr_in_flight+0x2d0/0x2d0 [ 61.015418][ T596] ? rwlock_bug.part.0+0x90/0x90 [ 61.020348][ T596] worker_thread+0x64c/0x1120 [ 61.025030][ T596] ? __kthread_parkme+0x13f/0x1e0 [ 61.030045][ T596] ? process_one_work+0x1670/0x1670 [ 61.035234][ T596] kthread+0x3b5/0x4a0 [ 61.039298][ T596] ? __kthread_bind_mask+0xc0/0xc0 [ 61.044398][ T596] ? __kthread_bind_mask+0xc0/0xc0 [ 61.049502][ T596] ret_from_fork+0x1f/0x30 [ 61.055270][ T596] Kernel Offset: disabled [ 61.059633][ T596] Rebooting in 86400 seconds..