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Subject: Re: [PATCH] usb: appledisplay: fix use-after-free in
 bl_get_brightness
From:   Oliver Neukum <oneukum@suse.com>
To:     Phong Tran <tranmanphong@gmail.com>,
        syzbot+495dab1f175edc9c2f13@syzkaller.appspotmail.com
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Date:   Thu, 07 Nov 2019 09:50:29 +0100
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Am Mittwoch, den 06.11.2019, 21:22 +0700 schrieb Phong Tran:

> compare with message size (2) can be considered.
> 
> if (retval == 2) {
> 	brightness = pdata->msgdata[1];
> } else {
> 	retval = -EMSGSIZE;
> }

If you do it that way, the error reporting will be distorted.
Hence I did it a bit more complexly.

	Regards
		Oliver