Re: [syzbot] Re: [syzbot] [input?] possible deadlock in input_ff_flush

syzbot
2025-01-06T10:29:50Z

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Subject: Re: [syzbot] [input?] possible deadlock in input_ff_flush
Author: hdanton@sina.com

On Sun, 05 Jan 2025 04:40:19 -0800
> syzbot found the following issue on:
>
> HEAD commit: ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g..
> git tree: upstream
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17bd56df980000

#syz test

--- x/drivers/input/input.c
+++ y/drivers/input/input.c
@@ -642,17 +642,11 @@ EXPORT_SYMBOL(input_open_device);
int input_flush_device(struct input_handle *handle, struct file *file)
{
struct input_dev *dev = handle->dev;
- int retval;
-
- retval = mutex_lock_interruptible(&dev->mutex);
- if (retval)
- return retval;

if (dev->flush)
- retval = dev->flush(dev, file);
+ return dev->flush(dev, file);

- mutex_unlock(&dev->mutex);
- return retval;
+ return 0;
}
EXPORT_SYMBOL(input_flush_device);

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