[ 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 '10.128.0.74' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 54.409614][ T6778] input: syz0 as /devices/virtual/input/input5 [ 54.421902][ T6778] ================================================================== [ 54.430085][ T6778] BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 [ 54.437273][ T6778] Read of size 8 at addr ffff88809f9ae158 by task syz-executor788/6778 [ 54.445499][ T6778] [ 54.447831][ T6778] CPU: 0 PID: 6778 Comm: syz-executor788 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 [ 54.457702][ T6778] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 54.467745][ T6778] Call Trace: [ 54.471036][ T6778] dump_stack+0x18f/0x20d [ 54.475345][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 54.480354][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 54.485180][ T6778] print_address_description.constprop.0.cold+0xd3/0x413 [ 54.492174][ T6778] ? cdev_device_del+0x69/0x80 [ 54.496947][ T6778] ? evdev_disconnect+0x3d/0xb0 [ 54.501804][ T6778] ? __input_unregister_device+0x1b0/0x430 [ 54.507581][ T6778] ? input_unregister_device+0xb4/0xf0 [ 54.513012][ T6778] ? uinput_destroy_device+0x1e2/0x240 [ 54.518445][ T6778] ? vprintk_func+0x97/0x1a6 [ 54.523010][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 54.527830][ T6778] kasan_report.cold+0x1f/0x37 [ 54.532654][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 54.537511][ T6778] __mutex_lock+0x1033/0x13c0 [ 54.542164][ T6778] ? evdev_cleanup+0x21/0x190 [ 54.546815][ T6778] ? print_usage_bug+0x240/0x240 [ 54.551747][ T6778] ? trace_hardirqs_off+0x50/0x220 [ 54.556852][ T6778] ? mutex_trylock+0x2c0/0x2c0 [ 54.561589][ T6778] ? mark_held_locks+0x9f/0xe0 [ 54.566327][ T6778] ? kfree+0x1eb/0x2b0 [ 54.570369][ T6778] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 54.576323][ T6778] ? kfree_const+0x51/0x60 [ 54.580716][ T6778] ? evdev_cleanup+0x21/0x190 [ 54.585365][ T6778] evdev_cleanup+0x21/0x190 [ 54.589841][ T6778] evdev_disconnect+0x45/0xb0 [ 54.594491][ T6778] __input_unregister_device+0x1b0/0x430 [ 54.600096][ T6778] input_unregister_device+0xb4/0xf0 [ 54.605356][ T6778] uinput_destroy_device+0x1e2/0x240 [ 54.610616][ T6778] ? uinput_destroy_device+0x240/0x240 [ 54.616045][ T6778] uinput_release+0x37/0x50 [ 54.620543][ T6778] __fput+0x33e/0x880 [ 54.624502][ T6778] task_work_run+0xf4/0x1b0 [ 54.628980][ T6778] do_exit+0xb5e/0x2e10 [ 54.633112][ T6778] ? fsnotify_first_mark+0x191/0x200 [ 54.638378][ T6778] ? uinput_dev_upload_effect+0x1e0/0x1e0 [ 54.644082][ T6778] ? mm_update_next_owner+0x7a0/0x7a0 [ 54.649445][ T6778] ? vfs_write+0x161/0x5d0 [ 54.653849][ T6778] do_group_exit+0x125/0x340 [ 54.658410][ T6778] __x64_sys_exit_group+0x3a/0x50 [ 54.663408][ T6778] do_syscall_64+0xf6/0x7d0 [ 54.672584][ T6778] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 54.678467][ T6778] RIP: 0033:0x43fa18 [ 54.682342][ T6778] Code: Bad RIP value. [ 54.686378][ T6778] RSP: 002b:00007fff12b4a8b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 54.694759][ T6778] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fa18 [ 54.702701][ T6778] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 54.710643][ T6778] RBP: 00000000004bf268 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 54.718599][ T6778] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 54.726552][ T6778] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 54.734505][ T6778] [ 54.736805][ T6778] Allocated by task 6778: [ 54.741110][ T6778] save_stack+0x1b/0x40 [ 54.745242][ T6778] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 54.750844][ T6778] kmem_cache_alloc_trace+0x153/0x7d0 [ 54.756192][ T6778] evdev_connect+0x80/0x4d0 [ 54.760668][ T6778] input_attach_handler+0x194/0x200 [ 54.765836][ T6778] input_register_device.cold+0xf5/0x246 [ 54.771443][ T6778] uinput_ioctl_handler.isra.0+0x1210/0x1d80 [ 54.777394][ T6778] ksys_ioctl+0x11a/0x180 [ 54.781693][ T6778] __x64_sys_ioctl+0x6f/0xb0 [ 54.786254][ T6778] do_syscall_64+0xf6/0x7d0 [ 54.790729][ T6778] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 54.796586][ T6778] [ 54.798896][ T6778] Freed by task 6778: [ 54.802852][ T6778] save_stack+0x1b/0x40 [ 54.806978][ T6778] __kasan_slab_free+0xf7/0x140 [ 54.811797][ T6778] kfree+0x109/0x2b0 [ 54.815663][ T6778] device_release+0x71/0x200 [ 54.820222][ T6778] kobject_put+0x1c8/0x2f0 [ 54.824613][ T6778] cdev_device_del+0x69/0x80 [ 54.829173][ T6778] evdev_disconnect+0x3d/0xb0 [ 54.833820][ T6778] __input_unregister_device+0x1b0/0x430 [ 54.839420][ T6778] input_unregister_device+0xb4/0xf0 [ 54.844675][ T6778] uinput_destroy_device+0x1e2/0x240 [ 54.849929][ T6778] uinput_release+0x37/0x50 [ 54.854402][ T6778] __fput+0x33e/0x880 [ 54.858357][ T6778] task_work_run+0xf4/0x1b0 [ 54.862831][ T6778] do_exit+0xb5e/0x2e10 [ 54.866956][ T6778] do_group_exit+0x125/0x340 [ 54.871517][ T6778] __x64_sys_exit_group+0x3a/0x50 [ 54.876512][ T6778] do_syscall_64+0xf6/0x7d0 [ 54.880986][ T6778] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 54.886841][ T6778] [ 54.889143][ T6778] The buggy address belongs to the object at ffff88809f9ae000 [ 54.889143][ T6778] which belongs to the cache kmalloc-2k of size 2048 [ 54.903165][ T6778] The buggy address is located 344 bytes inside of [ 54.903165][ T6778] 2048-byte region [ffff88809f9ae000, ffff88809f9ae800) [ 54.916498][ T6778] The buggy address belongs to the page: [ 54.922109][ T6778] page:ffffea00027e6b80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 54.931183][ T6778] flags: 0xfffe0000000200(slab) [ 54.936007][ T6778] raw: 00fffe0000000200 ffffea00027fdd88 ffffea00027e6d48 ffff8880aa000e00 [ 54.944563][ T6778] raw: 0000000000000000 ffff88809f9ae000 0000000100000001 0000000000000000 [ 54.953112][ T6778] page dumped because: kasan: bad access detected [ 54.959493][ T6778] [ 54.961791][ T6778] Memory state around the buggy address: [ 54.967393][ T6778] ffff88809f9ae000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 54.975438][ T6778] ffff88809f9ae080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 54.983470][ T6778] >ffff88809f9ae100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 54.991504][ T6778] ^ [ 54.998417][ T6778] ffff88809f9ae180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 55.006476][ T6778] ffff88809f9ae200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 55.014515][ T6778] ================================================================== [ 55.022552][ T6778] Disabling lock debugging due to kernel taint [ 55.029612][ T6778] Kernel panic - not syncing: panic_on_warn set ... [ 55.036200][ T6778] CPU: 0 PID: 6778 Comm: syz-executor788 Tainted: G B 5.7.0-rc6-next-20200522-syzkaller #0 [ 55.047461][ T6778] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 55.057503][ T6778] Call Trace: [ 55.060790][ T6778] dump_stack+0x18f/0x20d [ 55.065106][ T6778] ? __mutex_lock+0xf50/0x13c0 [ 55.069867][ T6778] panic+0x2e3/0x75c [ 55.073758][ T6778] ? __warn_printk+0xf3/0xf3 [ 55.078322][ T6778] ? preempt_schedule_common+0x5e/0xc0 [ 55.083750][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 55.088573][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 55.093396][ T6778] ? preempt_schedule_thunk+0x16/0x18 [ 55.098741][ T6778] ? trace_hardirqs_on+0x55/0x230 [ 55.103735][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 55.108552][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 55.113374][ T6778] end_report+0x4d/0x53 [ 55.117499][ T6778] kasan_report.cold+0xd/0x37 [ 55.122171][ T6778] ? __mutex_lock+0x1033/0x13c0 [ 55.126991][ T6778] __mutex_lock+0x1033/0x13c0 [ 55.131640][ T6778] ? evdev_cleanup+0x21/0x190 [ 55.136286][ T6778] ? print_usage_bug+0x240/0x240 [ 55.141202][ T6778] ? trace_hardirqs_off+0x50/0x220 [ 55.146282][ T6778] ? mutex_trylock+0x2c0/0x2c0 [ 55.151062][ T6778] ? mark_held_locks+0x9f/0xe0 [ 55.155797][ T6778] ? kfree+0x1eb/0x2b0 [ 55.159836][ T6778] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 55.165784][ T6778] ? kfree_const+0x51/0x60 [ 55.170171][ T6778] ? evdev_cleanup+0x21/0x190 [ 55.174817][ T6778] evdev_cleanup+0x21/0x190 [ 55.179293][ T6778] evdev_disconnect+0x45/0xb0 [ 55.183942][ T6778] __input_unregister_device+0x1b0/0x430 [ 55.189548][ T6778] input_unregister_device+0xb4/0xf0 [ 55.194805][ T6778] uinput_destroy_device+0x1e2/0x240 [ 55.200064][ T6778] ? uinput_destroy_device+0x240/0x240 [ 55.205491][ T6778] uinput_release+0x37/0x50 [ 55.209965][ T6778] __fput+0x33e/0x880 [ 55.213921][ T6778] task_work_run+0xf4/0x1b0 [ 55.218418][ T6778] do_exit+0xb5e/0x2e10 [ 55.222558][ T6778] ? fsnotify_first_mark+0x191/0x200 [ 55.227816][ T6778] ? uinput_dev_upload_effect+0x1e0/0x1e0 [ 55.233504][ T6778] ? mm_update_next_owner+0x7a0/0x7a0 [ 55.238854][ T6778] ? vfs_write+0x161/0x5d0 [ 55.243242][ T6778] do_group_exit+0x125/0x340 [ 55.247802][ T6778] __x64_sys_exit_group+0x3a/0x50 [ 55.252800][ T6778] do_syscall_64+0xf6/0x7d0 [ 55.257288][ T6778] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 55.263151][ T6778] RIP: 0033:0x43fa18 [ 55.267023][ T6778] Code: Bad RIP value. [ 55.271059][ T6778] RSP: 002b:00007fff12b4a8b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 55.279438][ T6778] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043fa18 [ 55.287382][ T6778] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 55.295326][ T6778] RBP: 00000000004bf268 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 55.303283][ T6778] R10: 00000000004002c8 R11: 0000000000000246 R12: 0000000000000001 [ 55.311228][ T6778] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 55.320245][ T6778] Kernel Offset: disabled [ 55.324567][ T6778] Rebooting in 86400 seconds..