Re: [PATCH v2] net/ipv4/tcp_cong: Replace strncpy() with strscpy()

[Eric Dumazet]

On Tue, Jul 16, 2024 at 4:32 AM Paolo Abeni <pabeni@xxxxxxxxxx> wrote:
>
> On 7/15/24 11:41, Simon Horman wrote:
> > On Sat, Jul 13, 2024 at 09:11:15PM -0700, Kees Cook wrote:
> >> Replace the deprecated[1] uses of strncpy() in tcp_ca_get_name_by_key()
> >> and tcp_get_default_congestion_control(). The callers use the results as
> >> standard C strings (via nla_put_string() and proc handlers respectively),
> >> so trailing padding is not needed.
> >>
> >> Since passing the destination buffer arguments decays it to a pointer,
> >> the size can't be trivially determined by the compiler. ca->name is
> >> the same length in both cases, so strscpy() won't fail (when ca->name
> >> is NUL-terminated). Include the length explicitly instead of using the
> >> 2-argument strscpy().
> >>
> >> Link: https://github.com/KSPP/linux/issues/90 [1]
> >> Signed-off-by: Kees Cook <kees@xxxxxxxxxx>
> >
> > nit: Looking at git history, the subject prefix should probably be 'tcp'.
> >       And it would be best to explicitly target the patch against net-next.
> >
> >       Subject: [PATCH net-next v2] tcp: ...
> >
> > That notwithstanding, this looks good to me.
> >
> > Reviewed-by: Simon Horman <horms@xxxxxxxxxx>
>
> @Eric: I can fix the prefix when applying the patch. Please LMK if you
> prefer otherwise.

Sure thing, thanks for taking care of this Paolo, Simon, and Kees.

Reviewed-by: Eric Dumazet <edumazet@xxxxxxxxxx>