From: Kees Cook <keescook@chromium.org>
To: Justin Stitt <justinstitt@google.com>
Cc: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>,
Maxime Ripard <mripard@kernel.org>,
Thomas Zimmermann <tzimmermann@suse.de>,
David Airlie <airlied@gmail.com>, Daniel Vetter <daniel@ffwll.ch>,
dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org,
linux-hardening@vger.kernel.org, Xu Panda <xu.panda@zte.com.cn>
Subject: Re: [PATCH] drm/modes: refactor deprecated strncpy
Date: Thu, 14 Sep 2023 21:30:43 -0700 [thread overview]
Message-ID: <202309142129.46C1EAE2E2@keescook> (raw)
In-Reply-To: <20230914-strncpy-drivers-gpu-drm-drm_modes-c-v1-1-079b532553a3@google.com>
On Thu, Sep 14, 2023 at 06:08:44PM +0000, Justin Stitt wrote:
> `strncpy` is deprecated for use on NUL-terminated destination strings [1].
>
> We should prefer more robust and less ambiguous string interfaces.
>
> A suitable replacement is `strscpy` [2] due to the fact that it guarantees
> NUL-termination on the destination buffer and doesn't incur the
> performance loss of unnecessarily NUL-padding.
How did you decide it didn't need %NUL padding?
I suspect it should have it, as I see what looks like full struct copies
happening in places:
struct drm_mode_modeinfo umode;
...
struct drm_property_blob *blob;
drm_mode_convert_to_umode(&umode, mode);
blob = drm_property_create_blob(crtc->dev,
sizeof(umode), &umode);
Can you send a v2 using strscpy_pad() instead?
Thanks!
-Kees
--
Kees Cook
prev parent reply other threads:[~2023-09-15 4:30 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-14 18:08 Justin Stitt
2023-09-15 4:30 ` Kees Cook [this message]
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=202309142129.46C1EAE2E2@keescook \
--to=keescook@chromium.org \
--cc=airlied@gmail.com \
--cc=daniel@ffwll.ch \
--cc=dri-devel@lists.freedesktop.org \
--cc=justinstitt@google.com \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=maarten.lankhorst@linux.intel.com \
--cc=mripard@kernel.org \
--cc=tzimmermann@suse.de \
--cc=xu.panda@zte.com.cn \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox
all inboxes | Powered by JetHome®