Re: the nul-terminated string helper desk chair rearrangement

Justin Stitt
2023-10-20T17:40:27Z

On Thu, Oct 19, 2023 at 9:46 PM Christoph Hellwig <hch@lst.de> wrote:
>
> On Wed, Oct 18, 2023 at 11:01:54PM -0700, Kees Cook wrote:
> > Almost all of the remaining strncpy() usage is just string to string
> > copying, but the corner cases that are being spun out that aren't
> > strscpy() or strscpy_pad() are covered by strtomem(), kmemdup_nul(),
> > and memcpy(). Each of these are a clear improvement since they remove
> > the ambiguity of the intended behavior. Using seq_buf ends up being way
> > more overhead than is needed.
>
> I'm really not sure strscpy is much of an improvement. In this particular
> case in most other places we simply use a snprintf for nqns, which seems
> useful here to if we don't want the full buf.
>
> But switching to a completely undocumented helper like strscpy seems not
> useful at all.

There's some docs at [1]. Perhaps there could be more?

[1]: https://elixir.bootlin.com/linux/v6.6-rc6/source/include/linux/fortify-string.h#L292