From: Anthony Liguori <anthony@codemonkey.ws>
To: Peter Lieven <pl@kamp.de>
Cc: Gerd Hoffmann <kraxel@redhat.com>,
"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Subject: Re: [Qemu-devel] possible denial of service via VNC
Date: Sun, 29 Jun 2014 10:12:13 -0700 [thread overview]
Message-ID: <CA+aC4ksHYZLs1sCmGPD83r6JxwP=fELY=FuZ2qkdeht9JBzgCQ@mail.gmail.com> (raw)
In-Reply-To: <53B003B2.2020309@kamp.de>
On Sun, Jun 29, 2014 at 5:16 AM, Peter Lieven <pl@kamp.de> wrote:
> Hi,
>
> while debugging a VNC issue I found this:
>
> case VNC_MSG_CLIENT_CUT_TEXT:
> if (len == 1)
> return 8;
>
> if (len == 8) {
> uint32_t dlen = read_u32(data, 4);
> if (dlen > 0)
> return 8 + dlen;
> }
>
> client_cut_text(vs, read_u32(data, 4), data + 8);
> break;
>
> in protocol_client_msg().
>
> Is this really a good idea? This allows for letting the vs->input buffer to grow
> up to 2^32 + 8 byte which will possibly result in an out of memory condition.
The spec allows cut operations of this size. What would a reasonable limit be?
Regards,
Anthony Liguori
> PeterY
>
>
next prev parent reply other threads:[~2014-06-29 17:12 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2014-06-29 12:16 [Qemu-devel] possible denial of service via VNC Peter Lieven
2014-06-29 17:12 ` Anthony Liguori [this message]
2014-06-30 7:33 ` Gerd Hoffmann
2014-06-30 7:45 ` Peter Lieven
2014-06-30 7:46 ` Gerd Hoffmann
2014-06-30 7:51 ` Peter Lieven
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='CA+aC4ksHYZLs1sCmGPD83r6JxwP=fELY=FuZ2qkdeht9JBzgCQ@mail.gmail.com' \
--to=anthony@codemonkey.ws \
--cc=kraxel@redhat.com \
--cc=pl@kamp.de \
--cc=qemu-devel@nongnu.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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.