From: Steven Rostedt <rostedt@goodmis.org>
To: Dan Rosenberg <drosenberg@vsecurity.com>
Cc: JosephChan@via.com.tw, ScottFang@viatech.com.cn,
linux-fbdev@vger.kernel.org, linux-kernel@vger.kernel.org,
security@kernel.org, stable@kernel.org
Subject: Re: [PATCH] drivers/video/via/ioctl.c: prevent reading
Date: Thu, 16 Sep 2010 16:07:45 +0000 [thread overview]
Message-ID: <20100916160745.GC14318@home.goodmis.org> (raw)
In-Reply-To: <1284587059.6275.101.camel@dan>
On Wed, Sep 15, 2010 at 05:44:19PM -0400, Dan Rosenberg wrote:
> The VIAFB_GET_INFO device ioctl allows unprivileged users to read 1968
> bytes of uninitialized stack memory, because the "reserved" member of
> the viafb_ioctl_info struct declared on the stack is not altered or
> zeroed before being copied back to the user. This patch takes care of
> it.
>
> Signed-off-by: Dan Rosenberg <dan.j.rosenberg@gmail.com>
>
> --- linux-2.6.35.4.orig/drivers/video/via/ioctl.c 2010-08-26 19:47:12.000000000 -0400
> +++ linux-2.6.35.4/drivers/video/via/ioctl.c 2010-09-15 11:53:29.997375748 -0400
> @@ -25,6 +25,8 @@ int viafb_ioctl_get_viafb_info(u_long ar
> {
> struct viafb_ioctl_info viainfo;
>
> + memset(&viainfo, 0, sizeof(struct viafb_ioctl));
> +
Again, this could probably be better off as:
- struct viafb_ioctl_info viainfo;
+ struct viafb_ioctl_info viainfo = {
+ .viafb_id = VIAID,
+ .vendor_id = PCI_VIA_VENDOR_ID,
+ };
- viainfo.viafb_id = VIAID;
- viainfo.vendor_id = PCI_VIA_VENDOR_ID;
-- Steve
> viainfo.viafb_id = VIAID;
> viainfo.vendor_id = PCI_VIA_VENDOR_ID;
>
>
>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
prev parent reply other threads:[~2010-09-16 16:07 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2010-09-15 21:44 [PATCH] drivers/video/via/ioctl.c: prevent reading uninitialized Dan Rosenberg
2010-09-15 22:42 ` Florian Tobias Schandinat
2010-09-16 16:07 ` Steven Rostedt [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=20100916160745.GC14318@home.goodmis.org \
--to=rostedt@goodmis.org \
--cc=JosephChan@via.com.tw \
--cc=ScottFang@viatech.com.cn \
--cc=drosenberg@vsecurity.com \
--cc=linux-fbdev@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=security@kernel.org \
--cc=stable@kernel.org \
/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;
as well as URLs for NNTP newsgroup(s).