Re: [PATCH] dns: remove redundant zero length namelen check

From: David Howells
Date: Fri Apr 12 2019 - 06:20:01 EST


David Miller <davem@xxxxxxxxxxxxx> wrote:

> > The zero namelen check is redundant as it has already been checked
> > for zero at the start of the function. Remove the redundant check.
> >
> > Addresses-Coverity: ("Logically Dead Code")
> > Signed-off-by: Colin Ian King <colin.king@xxxxxxxxxxxxx>
>
> Applied to net-next.
>
> However it does look like two sets of semantics were considered.
> In one case rejecting a zero namelen and in another having it
> mean whatever the strings length is modulo the max of 256.

It probably makes sense to merge the:

if (namelen < 3 || namelen > 255)
return -EINVAL;

check into the earlier:

if (!name || namelen == 0)
return -EINVAL;

check too.

David