Subject: Re: dev_ifname32() fails on 32->64bit calls in copy_in_user().

From: Benjamin Herrenschmidt <[email-masked]>
Date: Wed, 31 Oct 2007 13:35:24 +1100

Bug is in the new dev_ifname32:

	uifr = compat_alloc_user_space(sizeof(struct ifreq));
	if (copy_in_user(uifr, compat_ptr(arg), sizeof(struct ifreq32)));
		return -EFAULT;

There's a stray ";" after the if statement, that was obviously not
tested :-)

This fixes it here (tested):
----------------------------------------------------------------------------
[PATCH] Fix new dev_ifname32 returning -EFAULT

A stray semicolon slipped in the patch that updated dev_ifname32 to
not be inline, causing it to always return -EFAULT. This fixes it.

Signed-off-by: Benjamin Herrenschmidt <[email-masked]>
---

Index: linux-work/fs/compat_ioctl.c
===================================================================
--- linux-work.orig/fs/compat_ioctl.c	2007-10-31 13:30:42.000000000 +1100
+++ linux-work/fs/compat_ioctl.c	2007-10-31 13:30:46.000000000 +1100
@@ -322,7 +322,7 @@ static int dev_ifname32(unsigned int fd,
 	int err;
 
 	uifr = compat_alloc_user_space(sizeof(struct ifreq));
-	if (copy_in_user(uifr, compat_ptr(arg), sizeof(struct ifreq32)));
+	if (copy_in_user(uifr, compat_ptr(arg), sizeof(struct ifreq32)))
 		return -EFAULT;
 
 	err = sys_ioctl(fd, SIOCGIFNAME, (unsigned long)uifr);