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From: Peter Lieven <pl@kamp.de>
To: Gerd Hoffmann <kraxel@redhat.com>,
	"qemu-devel@nongnu.org" <qemu-devel@nongnu.org>
Subject: [Qemu-devel] possible denial of service via VNC
Date: Sun, 29 Jun 2014 14:16:50 +0200	[thread overview]
Message-ID: <53B003B2.2020309@kamp.de> (raw)

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.

Peter

             reply	other threads:[~2014-06-29 12:17 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-06-29 12:16 Peter Lieven [this message]
2014-06-29 17:12 ` [Qemu-devel] possible denial of service via VNC Anthony Liguori
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

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