[ 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 '10.128.1.43' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 58.981416][ T6777] input: syz0 as /devices/virtual/input/input5 [ 58.995440][ T6777] ================================================================== [ 59.003655][ T6777] BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 [ 59.010860][ T6777] Read of size 8 at addr ffff8880a69ef158 by task syz-executor905/6777 [ 59.019095][ T6777] [ 59.021439][ T6777] CPU: 0 PID: 6777 Comm: syz-executor905 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 [ 59.031353][ T6777] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.041411][ T6777] Call Trace: [ 59.044709][ T6777] dump_stack+0x18f/0x20d [ 59.049051][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.053903][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.058747][ T6777] print_address_description.constprop.0.cold+0xd3/0x413 [ 59.065795][ T6777] ? cdev_device_del+0x69/0x80 [ 59.070573][ T6777] ? evdev_disconnect+0x3d/0xb0 [ 59.075415][ T6777] ? __input_unregister_device+0x1b0/0x430 [ 59.081220][ T6777] ? input_unregister_device+0xb4/0xf0 [ 59.086714][ T6777] ? uinput_destroy_device+0x1e2/0x240 [ 59.092199][ T6777] ? vprintk_func+0x97/0x1a6 [ 59.096777][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.101611][ T6777] kasan_report.cold+0x1f/0x37 [ 59.106364][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.111218][ T6777] __mutex_lock+0x1033/0x13c0 [ 59.115889][ T6777] ? evdev_cleanup+0x21/0x190 [ 59.120563][ T6777] ? print_usage_bug+0x240/0x240 [ 59.125483][ T6777] ? trace_hardirqs_off+0x50/0x220 [ 59.130600][ T6777] ? mutex_trylock+0x2c0/0x2c0 [ 59.135354][ T6777] ? mark_held_locks+0x9f/0xe0 [ 59.140109][ T6777] ? kfree+0x1eb/0x2b0 [ 59.144172][ T6777] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 59.150146][ T6777] ? kfree_const+0x51/0x60 [ 59.154553][ T6777] ? evdev_cleanup+0x21/0x190 [ 59.159244][ T6777] evdev_cleanup+0x21/0x190 [ 59.163767][ T6777] evdev_disconnect+0x45/0xb0 [ 59.168462][ T6777] __input_unregister_device+0x1b0/0x430 [ 59.174095][ T6777] input_unregister_device+0xb4/0xf0 [ 59.179368][ T6777] uinput_destroy_device+0x1e2/0x240 [ 59.184651][ T6777] ? uinput_destroy_device+0x240/0x240 [ 59.190101][ T6777] uinput_release+0x37/0x50 [ 59.194643][ T6777] __fput+0x33e/0x880 [ 59.198617][ T6777] task_work_run+0xf4/0x1b0 [ 59.203114][ T6777] do_exit+0xb5e/0x2e10 [ 59.207258][ T6777] ? fsnotify_first_mark+0x191/0x200 [ 59.212548][ T6777] ? uinput_dev_upload_effect+0x1e0/0x1e0 [ 59.218253][ T6777] ? mm_update_next_owner+0x7a0/0x7a0 [ 59.223605][ T6777] ? vfs_write+0x161/0x5d0 [ 59.228017][ T6777] do_group_exit+0x125/0x340 [ 59.232600][ T6777] __x64_sys_exit_group+0x3a/0x50 [ 59.237604][ T6777] do_syscall_64+0xf6/0x7d0 [ 59.242098][ T6777] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.247977][ T6777] RIP: 0033:0x43fa18 [ 59.251858][ T6777] Code: Bad RIP value. [ 59.255903][ T6777] RSP: 002b:00007ffcdb946908 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.264291][ T6777] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fa18 [ 59.272243][ T6777] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.280202][ T6777] RBP: 00000000004bf268 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.288164][ T6777] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 59.296119][ T6777] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 59.304077][ T6777] [ 59.306384][ T6777] Allocated by task 6777: [ 59.310694][ T6777] save_stack+0x1b/0x40 [ 59.314827][ T6777] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 59.320433][ T6777] kmem_cache_alloc_trace+0x153/0x7d0 [ 59.325788][ T6777] evdev_connect+0x80/0x4d0 [ 59.330279][ T6777] input_attach_handler+0x194/0x200 [ 59.335456][ T6777] input_register_device.cold+0xf5/0x246 [ 59.341068][ T6777] uinput_ioctl_handler.isra.0+0x1210/0x1d80 [ 59.347035][ T6777] ksys_ioctl+0x11a/0x180 [ 59.351341][ T6777] __x64_sys_ioctl+0x6f/0xb0 [ 59.355919][ T6777] do_syscall_64+0xf6/0x7d0 [ 59.360402][ T6777] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.366267][ T6777] [ 59.368577][ T6777] Freed by task 6777: [ 59.372539][ T6777] save_stack+0x1b/0x40 [ 59.376674][ T6777] __kasan_slab_free+0xf7/0x140 [ 59.381542][ T6777] kfree+0x109/0x2b0 [ 59.385430][ T6777] device_release+0x71/0x200 [ 59.389997][ T6777] kobject_put+0x1c8/0x2f0 [ 59.394399][ T6777] cdev_device_del+0x69/0x80 [ 59.398981][ T6777] evdev_disconnect+0x3d/0xb0 [ 59.403643][ T6777] __input_unregister_device+0x1b0/0x430 [ 59.409265][ T6777] input_unregister_device+0xb4/0xf0 [ 59.414542][ T6777] uinput_destroy_device+0x1e2/0x240 [ 59.419804][ T6777] uinput_release+0x37/0x50 [ 59.424285][ T6777] __fput+0x33e/0x880 [ 59.428254][ T6777] task_work_run+0xf4/0x1b0 [ 59.432738][ T6777] do_exit+0xb5e/0x2e10 [ 59.436868][ T6777] do_group_exit+0x125/0x340 [ 59.441437][ T6777] __x64_sys_exit_group+0x3a/0x50 [ 59.446444][ T6777] do_syscall_64+0xf6/0x7d0 [ 59.450947][ T6777] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.460245][ T6777] [ 59.462561][ T6777] The buggy address belongs to the object at ffff8880a69ef000 [ 59.462561][ T6777] which belongs to the cache kmalloc-2k of size 2048 [ 59.476602][ T6777] The buggy address is located 344 bytes inside of [ 59.476602][ T6777] 2048-byte region [ffff8880a69ef000, ffff8880a69ef800) [ 59.489981][ T6777] The buggy address belongs to the page: [ 59.495652][ T6777] page:ffffea00029a7bc0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 59.504754][ T6777] flags: 0xfffe0000000200(slab) [ 59.509596][ T6777] raw: 00fffe0000000200 ffffea00029a7b88 ffffea00029a7c88 ffff8880aa000e00 [ 59.518213][ T6777] raw: 0000000000000000 ffff8880a69ef000 0000000100000001 0000000000000000 [ 59.526782][ T6777] page dumped because: kasan: bad access detected [ 59.533174][ T6777] [ 59.535480][ T6777] Memory state around the buggy address: [ 59.541098][ T6777] ffff8880a69ef000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.549148][ T6777] ffff8880a69ef080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.557190][ T6777] >ffff8880a69ef100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.565226][ T6777] ^ [ 59.572141][ T6777] ffff8880a69ef180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.580188][ T6777] ffff8880a69ef200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 59.588233][ T6777] ================================================================== [ 59.596280][ T6777] Disabling lock debugging due to kernel taint [ 59.602905][ T6777] Kernel panic - not syncing: panic_on_warn set ... [ 59.609531][ T6777] CPU: 0 PID: 6777 Comm: syz-executor905 Tainted: G B 5.7.0-rc6-next-20200522-syzkaller #0 [ 59.620823][ T6777] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 59.630876][ T6777] Call Trace: [ 59.634174][ T6777] dump_stack+0x18f/0x20d [ 59.638507][ T6777] ? __mutex_lock+0xf50/0x13c0 [ 59.643264][ T6777] panic+0x2e3/0x75c [ 59.647135][ T6777] ? __warn_printk+0xf3/0xf3 [ 59.651720][ T6777] ? preempt_schedule_common+0x5e/0xc0 [ 59.657250][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.662082][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.666913][ T6777] ? preempt_schedule_thunk+0x16/0x18 [ 59.672300][ T6777] ? trace_hardirqs_on+0x55/0x230 [ 59.677304][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.682128][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.686962][ T6777] end_report+0x4d/0x53 [ 59.691616][ T6777] kasan_report.cold+0xd/0x37 [ 59.696265][ T6777] ? __mutex_lock+0x1033/0x13c0 [ 59.701090][ T6777] __mutex_lock+0x1033/0x13c0 [ 59.705742][ T6777] ? evdev_cleanup+0x21/0x190 [ 59.710393][ T6777] ? print_usage_bug+0x240/0x240 [ 59.715314][ T6777] ? trace_hardirqs_off+0x50/0x220 [ 59.720415][ T6777] ? mutex_trylock+0x2c0/0x2c0 [ 59.725157][ T6777] ? mark_held_locks+0x9f/0xe0 [ 59.729911][ T6777] ? kfree+0x1eb/0x2b0 [ 59.734001][ T6777] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 59.739970][ T6777] ? kfree_const+0x51/0x60 [ 59.744366][ T6777] ? evdev_cleanup+0x21/0x190 [ 59.749055][ T6777] evdev_cleanup+0x21/0x190 [ 59.753541][ T6777] evdev_disconnect+0x45/0xb0 [ 59.758196][ T6777] __input_unregister_device+0x1b0/0x430 [ 59.763816][ T6777] input_unregister_device+0xb4/0xf0 [ 59.769078][ T6777] uinput_destroy_device+0x1e2/0x240 [ 59.774342][ T6777] ? uinput_destroy_device+0x240/0x240 [ 59.779836][ T6777] uinput_release+0x37/0x50 [ 59.784332][ T6777] __fput+0x33e/0x880 [ 59.788328][ T6777] task_work_run+0xf4/0x1b0 [ 59.792817][ T6777] do_exit+0xb5e/0x2e10 [ 59.796951][ T6777] ? fsnotify_first_mark+0x191/0x200 [ 59.802316][ T6777] ? uinput_dev_upload_effect+0x1e0/0x1e0 [ 59.808072][ T6777] ? mm_update_next_owner+0x7a0/0x7a0 [ 59.813429][ T6777] ? vfs_write+0x161/0x5d0 [ 59.817823][ T6777] do_group_exit+0x125/0x340 [ 59.822391][ T6777] __x64_sys_exit_group+0x3a/0x50 [ 59.827401][ T6777] do_syscall_64+0xf6/0x7d0 [ 59.831895][ T6777] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 59.837763][ T6777] RIP: 0033:0x43fa18 [ 59.841639][ T6777] Code: Bad RIP value. [ 59.845679][ T6777] RSP: 002b:00007ffcdb946908 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 59.854073][ T6777] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fa18 [ 59.862116][ T6777] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 59.870110][ T6777] RBP: 00000000004bf268 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 59.878062][ T6777] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 59.886014][ T6777] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 59.895064][ T6777] Kernel Offset: disabled [ 59.899386][ T6777] Rebooting in 86400 seconds..