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Message-ID: <43da274f22acaae8b917f51f6e62376928163e8f.camel@redhat.com>
Subject: Re: [PATCH] drm/nouveau/pm: refactor deprecated strncpy
From:   Lyude Paul <lyude@redhat.com>
To:     Kees Cook <keescook@chromium.org>,
        Justin Stitt <justinstitt@google.com>
Cc:     Ben Skeggs <bskeggs@redhat.com>, Karol Herbst <kherbst@redhat.com>,
        David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        dri-devel@lists.freedesktop.org, nouveau@lists.freedesktop.org,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Date:   Fri, 15 Sep 2023 13:32:50 -0400
In-Reply-To: <202309142158.59A6C62F@keescook>
References: <20230914-strncpy-drivers-gpu-drm-nouveau-nvkm-engine-pm-base-c-v1-1-4b09ed453f84@google.com>
         <202309142158.59A6C62F@keescook>
Organization: Red Hat Inc.
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Nice catch!

Reviewed-by: Lyude Paul <lyude@redhat.com>

Will push in just a moment

On Thu, 2023-09-14 at 21:59 -0700, Kees Cook wrote:
> On Thu, Sep 14, 2023 at 10:17:08PM +0000, Justin Stitt wrote:
> > `strncpy` is deprecated for use on NUL-terminated destination strings [=
1].
> >=20
> > We should prefer more robust and less ambiguous string interfaces.
> >=20
> > A suitable replacement is `strscpy` [2] due to the fact that it guarant=
ees
> > NUL-termination on the destination buffer without unnecessarily NUL-pad=
ding.
> >=20
> > Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#st=
rncpy-on-nul-terminated-strings [1]
> > Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en=
.html [2]
> > Link: https://github.com/KSPP/linux/issues/90
> > Cc: linux-hardening@vger.kernel.org
> > Signed-off-by: Justin Stitt <justinstitt@google.com>
>=20
> The "- 1" use in the original code is strong evidence for this being a
> sane conversion. :)
>=20
> Reviewed-by: Kees Cook <keescook@chromium.org>
>=20

--=20
Cheers,
 Lyude Paul (she/her)
 Software Engineer at Red Hat