Debian GNU/Linux 9 syzkaller ttyS0 Warning: Permanently added '10.128.0.226' (ECDSA) to the list of known hosts. executing program syzkaller login: [ 56.017261][ T6834] input: syz1 as /devices/virtual/input/input5 [ 56.030546][ T6834] ================================================================== [ 56.038850][ T6834] BUG: KASAN: use-after-free in __mutex_lock+0x1033/0x13c0 [ 56.046941][ T6834] Read of size 8 at addr ffff8880a7a80158 by task syz-executor861/6834 [ 56.055210][ T6834] [ 56.057919][ T6834] CPU: 1 PID: 6834 Comm: syz-executor861 Not tainted 5.7.0-rc6-next-20200522-syzkaller #0 [ 56.069282][ T6834] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.079487][ T6834] Call Trace: [ 56.082791][ T6834] dump_stack+0x18f/0x20d [ 56.087368][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.092199][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.097036][ T6834] print_address_description.constprop.0.cold+0xd3/0x413 [ 56.104169][ T6834] ? cdev_device_del+0x69/0x80 [ 56.110228][ T6834] ? evdev_disconnect+0x3d/0xb0 [ 56.115061][ T6834] ? __input_unregister_device+0x1b0/0x430 [ 56.120867][ T6834] ? input_unregister_device+0xb4/0xf0 [ 56.126324][ T6834] ? uinput_destroy_device+0x1e2/0x240 [ 56.131879][ T6834] ? vprintk_func+0x97/0x1a6 [ 56.136465][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.141294][ T6834] kasan_report.cold+0x1f/0x37 [ 56.146038][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.150888][ T6834] __mutex_lock+0x1033/0x13c0 [ 56.155548][ T6834] ? evdev_cleanup+0x21/0x190 [ 56.160230][ T6834] ? print_usage_bug+0x240/0x240 [ 56.165150][ T6834] ? trace_hardirqs_off+0x50/0x220 [ 56.170268][ T6834] ? mutex_trylock+0x2c0/0x2c0 [ 56.175489][ T6834] ? mark_held_locks+0x9f/0xe0 [ 56.184731][ T6834] ? kfree+0x1eb/0x2b0 [ 56.188801][ T6834] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 56.194860][ T6834] ? kfree_const+0x51/0x60 [ 56.199270][ T6834] ? evdev_cleanup+0x21/0x190 [ 56.204012][ T6834] evdev_cleanup+0x21/0x190 [ 56.209584][ T6834] evdev_disconnect+0x45/0xb0 [ 56.214313][ T6834] __input_unregister_device+0x1b0/0x430 [ 56.219975][ T6834] input_unregister_device+0xb4/0xf0 [ 56.225255][ T6834] uinput_destroy_device+0x1e2/0x240 [ 56.230739][ T6834] ? uinput_destroy_device+0x240/0x240 [ 56.236195][ T6834] uinput_release+0x37/0x50 [ 56.240699][ T6834] __fput+0x33e/0x880 [ 56.244947][ T6834] task_work_run+0xf4/0x1b0 [ 56.249446][ T6834] do_exit+0xb5e/0x2e10 [ 56.253596][ T6834] ? fsnotify_first_mark+0x191/0x200 [ 56.258865][ T6834] ? debug_smp_processor_id+0x2f/0x185 [ 56.264583][ T6834] ? mm_update_next_owner+0x7a0/0x7a0 [ 56.269934][ T6834] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 56.275906][ T6834] ? vfs_write+0x161/0x5d0 [ 56.280326][ T6834] do_group_exit+0x125/0x340 [ 56.285386][ T6834] __x64_sys_exit_group+0x3a/0x50 [ 56.290406][ T6834] do_syscall_64+0xf6/0x7d0 [ 56.294914][ T6834] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 56.300803][ T6834] RIP: 0033:0x43f9e8 [ 56.304700][ T6834] Code: Bad RIP value. [ 56.308748][ T6834] RSP: 002b:00007fff3ae6cc28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 56.317168][ T6834] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f9e8 [ 56.325306][ T6834] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 56.333254][ T6834] RBP: 00000000004bf228 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 56.341202][ T6834] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 56.349161][ T6834] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 56.357157][ T6834] [ 56.359466][ T6834] Allocated by task 6834: [ 56.363928][ T6834] save_stack+0x1b/0x40 [ 56.368074][ T6834] __kasan_kmalloc.constprop.0+0xbf/0xd0 [ 56.373691][ T6834] kmem_cache_alloc_trace+0x153/0x7d0 [ 56.379168][ T6834] evdev_connect+0x80/0x4d0 [ 56.383857][ T6834] input_attach_handler+0x194/0x200 [ 56.389428][ T6834] input_register_device.cold+0xf5/0x246 [ 56.395154][ T6834] uinput_ioctl_handler.isra.0+0x1210/0x1d80 [ 56.401389][ T6834] ksys_ioctl+0x11a/0x180 [ 56.405696][ T6834] __x64_sys_ioctl+0x6f/0xb0 [ 56.410268][ T6834] do_syscall_64+0xf6/0x7d0 [ 56.414760][ T6834] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 56.420643][ T6834] [ 56.422977][ T6834] Freed by task 6834: [ 56.426962][ T6834] save_stack+0x1b/0x40 [ 56.431205][ T6834] __kasan_slab_free+0xf7/0x140 [ 56.436163][ T6834] kfree+0x109/0x2b0 [ 56.440690][ T6834] device_release+0x71/0x200 [ 56.445455][ T6834] kobject_put+0x1c8/0x2f0 [ 56.449868][ T6834] cdev_device_del+0x69/0x80 [ 56.454450][ T6834] evdev_disconnect+0x3d/0xb0 [ 56.459152][ T6834] __input_unregister_device+0x1b0/0x430 [ 56.464787][ T6834] input_unregister_device+0xb4/0xf0 [ 56.470155][ T6834] uinput_destroy_device+0x1e2/0x240 [ 56.475421][ T6834] uinput_release+0x37/0x50 [ 56.480075][ T6834] __fput+0x33e/0x880 [ 56.484050][ T6834] task_work_run+0xf4/0x1b0 [ 56.488531][ T6834] do_exit+0xb5e/0x2e10 [ 56.493281][ T6834] do_group_exit+0x125/0x340 [ 56.498470][ T6834] __x64_sys_exit_group+0x3a/0x50 [ 56.503845][ T6834] do_syscall_64+0xf6/0x7d0 [ 56.508517][ T6834] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 56.514468][ T6834] [ 56.518950][ T6834] The buggy address belongs to the object at ffff8880a7a80000 [ 56.518950][ T6834] which belongs to the cache kmalloc-2k of size 2048 [ 56.533110][ T6834] The buggy address is located 344 bytes inside of [ 56.533110][ T6834] 2048-byte region [ffff8880a7a80000, ffff8880a7a80800) [ 56.546561][ T6834] The buggy address belongs to the page: [ 56.552273][ T6834] page:ffffea00029ea000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 [ 56.562250][ T6834] flags: 0xfffe0000000200(slab) [ 56.570304][ T6834] raw: 00fffe0000000200 ffffea0002761788 ffff8880aa001950 ffff8880aa000e00 [ 56.579053][ T6834] raw: 0000000000000000 ffff8880a7a80000 0000000100000001 0000000000000000 [ 56.587623][ T6834] page dumped because: kasan: bad access detected [ 56.594989][ T6834] [ 56.597323][ T6834] Memory state around the buggy address: [ 56.602955][ T6834] ffff8880a7a80000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.611030][ T6834] ffff8880a7a80080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.619159][ T6834] >ffff8880a7a80100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.627195][ T6834] ^ [ 56.634118][ T6834] ffff8880a7a80180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.643026][ T6834] ffff8880a7a80200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb [ 56.651597][ T6834] ================================================================== [ 56.659649][ T6834] Disabling lock debugging due to kernel taint [ 56.675177][ T6834] Kernel panic - not syncing: panic_on_warn set ... [ 56.682769][ T6834] CPU: 1 PID: 6834 Comm: syz-executor861 Tainted: G B 5.7.0-rc6-next-20200522-syzkaller #0 [ 56.694050][ T6834] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 [ 56.704281][ T6834] Call Trace: [ 56.708351][ T6834] dump_stack+0x18f/0x20d [ 56.713109][ T6834] ? __mutex_lock+0xf50/0x13c0 [ 56.717882][ T6834] panic+0x2e3/0x75c [ 56.721780][ T6834] ? __warn_printk+0xf3/0xf3 [ 56.726433][ T6834] ? preempt_schedule_common+0x5e/0xc0 [ 56.731863][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.736706][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.741545][ T6834] ? preempt_schedule_thunk+0x16/0x18 [ 56.746923][ T6834] ? trace_hardirqs_on+0x55/0x230 [ 56.751935][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.756967][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.762012][ T6834] end_report+0x4d/0x53 [ 56.766167][ T6834] kasan_report.cold+0xd/0x37 [ 56.770828][ T6834] ? __mutex_lock+0x1033/0x13c0 [ 56.775703][ T6834] __mutex_lock+0x1033/0x13c0 [ 56.780449][ T6834] ? evdev_cleanup+0x21/0x190 [ 56.785122][ T6834] ? print_usage_bug+0x240/0x240 [ 56.790213][ T6834] ? trace_hardirqs_off+0x50/0x220 [ 56.795316][ T6834] ? mutex_trylock+0x2c0/0x2c0 [ 56.800057][ T6834] ? mark_held_locks+0x9f/0xe0 [ 56.804806][ T6834] ? kfree+0x1eb/0x2b0 [ 56.809044][ T6834] ? lockdep_hardirqs_on_prepare+0x3a2/0x590 [ 56.815176][ T6834] ? kfree_const+0x51/0x60 [ 56.819745][ T6834] ? evdev_cleanup+0x21/0x190 [ 56.824395][ T6834] evdev_cleanup+0x21/0x190 [ 56.828972][ T6834] evdev_disconnect+0x45/0xb0 [ 56.833645][ T6834] __input_unregister_device+0x1b0/0x430 [ 56.839303][ T6834] input_unregister_device+0xb4/0xf0 [ 56.844572][ T6834] uinput_destroy_device+0x1e2/0x240 [ 56.849855][ T6834] ? uinput_destroy_device+0x240/0x240 [ 56.855417][ T6834] uinput_release+0x37/0x50 [ 56.860086][ T6834] __fput+0x33e/0x880 [ 56.864049][ T6834] task_work_run+0xf4/0x1b0 [ 56.868560][ T6834] do_exit+0xb5e/0x2e10 [ 56.872784][ T6834] ? fsnotify_first_mark+0x191/0x200 [ 56.878062][ T6834] ? debug_smp_processor_id+0x2f/0x185 [ 56.884108][ T6834] ? mm_update_next_owner+0x7a0/0x7a0 [ 56.890084][ T6834] ? rcu_read_lock_any_held.part.0+0x50/0x50 [ 56.896063][ T6834] ? vfs_write+0x161/0x5d0 [ 56.900482][ T6834] do_group_exit+0x125/0x340 [ 56.905066][ T6834] __x64_sys_exit_group+0x3a/0x50 [ 56.910256][ T6834] do_syscall_64+0xf6/0x7d0 [ 56.914740][ T6834] entry_SYSCALL_64_after_hwframe+0x49/0xb3 [ 56.920634][ T6834] RIP: 0033:0x43f9e8 [ 56.924603][ T6834] Code: Bad RIP value. [ 56.928652][ T6834] RSP: 002b:00007fff3ae6cc28 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7 [ 56.937772][ T6834] RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 000000000043f9e8 [ 56.945734][ T6834] RDX: 0000000000000000 RSI: 000000000000003c RDI: 0000000000000000 [ 56.953678][ T6834] RBP: 00000000004bf228 R08: 00000000000000e7 R09: ffffffffffffffd0 [ 56.962410][ T6834] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001 [ 56.970363][ T6834] R13: 00000000006d1180 R14: 0000000000000000 R15: 0000000000000000 [ 56.979623][ T6834] Kernel Offset: disabled [ 56.983960][ T6834] Rebooting in 86400 seconds..