Re: [PATCH][RFC] security: revalidate rw permissions for sys_splice and sys_vmsplice

[Andrew Morton <akpm@linux-foundation.org>]

On Wed, 30 May 2007 09:15:01 +0200
Jens Axboe <jens.axboe@oracle.com> wrote:

> On Tue, May 29 2007, James Morris wrote:
> > Revalidate read/write permissions for splice(2) and vmslice(2), in case 
> > security policy has changed since the files were opened.
> 
> I guess it was inevitably going to happen :-)
> 
> Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
> 

Probably acked-by was more appropriate.

James, is this considered needed-for-2.6.22?

> +	ret = security_file_permission(out, MAY_WRITE);
> +	if (unlikely(ret < 0))
> +		return ret;


ot: all the unlikely()s are irksome.  I wonder if there was some way of
doing this in security_file_permission() instead.  eg:

static inline int security_file_permission (struct file *file, int mask)
{
	int ret = security_ops->file_permission (file, mask);

	if (likely(ret == 0))
		return 0;
	return ret;
}