Subject: Re: [PATCH 1/2 v4] Driver for Freescale 8610 and 5121 DIU

From: Anton Vorontsov <[email-masked]>
Date: Fri, 28 Mar 2008 20:48:53 +0300

On Fri, Mar 28, 2008 at 12:30:29PM -0500, Scott Wood wrote:
> York Sun wrote:
> >+static int fsl_diu_ioctl(struct fb_info *info, unsigned int cmd,
> >+		       unsigned long arg)
> >+{
> >+	struct mfb_info *mfbi = info->par;
> >+	struct diu_ad *ad = mfbi->ad;
> >+	struct mfb_chroma_key ck;
> >+	unsigned char global_alpha;
> >+	struct aoi_display_offset aoi_d;
> >+	__u32 pix_fmt;
> >+
> >+	switch (cmd) {
> >+	case MFB_SET_PIXFMT:
> >+		if (!arg)
> >+			return -EINVAL;
> >+		if (copy_from_user(&pix_fmt, (void __user *)arg,
> >+				sizeof(pix_fmt)))
> 
> OK, you fixed the cast here...

Maybe better would be to define "buf" at the top of this function as
void __user *buf = (void __user *)arg;, i.e. just once?

> 
> >+			return -EFAULT;
> >+		ad->pix_fmt = pix_fmt;
> >+		pr_debug("Set pixel format to 0x%08x\n", ad->pix_fmt);
> >+		break;
> >+	case MFB_GET_PIXFMT:
> >+		if (!arg)
> >+			return -EINVAL;

This if (!arg) appears to be everywhere except default: label, maybe
this could be placed on top too?

> >+		pix_fmt = ad->pix_fmt;
> >+		if (copy_to_user((void *)arg, &pix_fmt, sizeof(pix_fmt)))
> >+			return -EFAULT;
> >+		pr_debug("get pixel format 0x%08x\n", ad->pix_fmt);
> >+		break;
> >+	case MFB_SET_AOID:
> >+		if (!arg)
> >+			return -EINVAL;
> >+		if (copy_from_user(&aoi_d, (void *)arg, sizeof(aoi_d)))
> >+			return -EFAULT;
> 
> ...but not anywhere else.  All user pointers should have a __user 
> annotation.

-- 
Anton Vorontsov
email: [email-masked]
irc://irc.freenode.net/bd2