Subject: Re: [PATCH] netfilter: ipset: Replace strlcpy with strscpy

From: Kees Cook <[email-masked]>
Date: Tue, 13 Jun 2023 12:26:28 -0700

On Tue, Jun 13, 2023 at 12:34:37AM +0000, Azeem Shaikh wrote:
> strlcpy() reads the entire source buffer first.
> This read may exceed the destination size limit.
> This is both inefficient and can lead to linear read
> overflows if a source string is not NUL-terminated [1].
> In an effort to remove strlcpy() completely [2], replace
> strlcpy() here with strscpy().
> 
> Direct replacement is safe here since return value from all
> callers of STRLCPY macro were ignored.

Yeah, the macro name is probably not super helpful here. It seems like
it should have originally be named IFNAME_CPY or something.

> 
> [1] https://www.kernel.org/doc/html/latest/process/deprecated.html#strlcpy
> [2] https://github.com/KSPP/linux/issues/89
> 
> Signed-off-by: Azeem Shaikh <[email-masked]>

But, regardless:

Reviewed-by: Kees Cook <[email-masked]>

-- 
Kees Cook