RE: [PATCH][3/4] let's kill verify_area - convert kernel/compat.c to access_ok()

["Peter Kjellerstedt" <peter.kjellerstedt@axis.com>]

> -----Original Message-----
> From: linux-kernel-owner@vger.kernel.org
[mailto:linux-kernel-owner@vger.kernel.org] On Behalf Of Jesper Juhl
> Sent: Friday, January 07, 2005 02:19
> To: linux-kernel
> Cc: Andrew Morton
> Subject: [PATCH][3/4] let's kill verify_area - convert kernel/compat.c
to access_ok()
> 
> Here's a patch to convert verify_area to access_ok in kernel/compat.c
> 
> diff -up linux-2.6.10-bk9-orig/kernel/compat.c 
> linux-2.6.10-bk9/kernel/compat.c
> --- linux-2.6.10-bk9-orig/kernel/compat.c	2005-01-06
22:19:13.000000000 +0100
> +++ linux-2.6.10-bk9/kernel/compat.c	2005-01-07 02:06:00.000000000
+0100

[snip]

> @@ -612,7 +612,7 @@ long compat_get_bitmap(unsigned long *ma
>  	/* align bitmap up to nearest compat_long_t boundary */
>  	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
>  
> -	if (verify_area(VERIFY_READ, umask, bitmap_size / 8))
> +	if (!access_ok(VERIFY_READ, umask, bitmap_size / 8) != 0)

Please do not use double negations (i.e., drop the '!= 0' test 
again).

>  		return -EFAULT;
>  
>  	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);
> @@ -653,7 +653,7 @@ long compat_put_bitmap(compat_ulong_t __
>  	/* align bitmap up to nearest compat_long_t boundary */
>  	bitmap_size = ALIGN(bitmap_size, BITS_PER_COMPAT_LONG);
>  
> -	if (verify_area(VERIFY_WRITE, umask, bitmap_size / 8))
> +	if (!access_ok(VERIFY_WRITE, umask, bitmap_size / 8) != 0)
>  		return -EFAULT;
>  
>  	nr_compat_longs = BITS_TO_COMPAT_LONGS(bitmap_size);

//Peter