From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756938AbZKWUXo (ORCPT ); Mon, 23 Nov 2009 15:23:44 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756817AbZKWUXo (ORCPT ); Mon, 23 Nov 2009 15:23:44 -0500 Received: from mail-ew0-f219.google.com ([209.85.219.219]:34989 "EHLO mail-ew0-f219.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756527AbZKWUXn (ORCPT ); Mon, 23 Nov 2009 15:23:43 -0500 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=message-id:date:from:user-agent:mime-version:to:subject :content-type:content-transfer-encoding; b=YzJmwEvT2kJIAlaITa+JI22TfH4vtmy6fcMG8/twtpoA7E7LnCEllyW0SXewD25BPQ MgI/tot1UIcPuyYfHA1YksBbFGmp5QyuqZbOasVtb8BMEZeOI4KyGCSj35SIkUZvNiTh ZO2H60LAJCwI1xmqzy0GnnJJqlcJmDmrBznas= Message-ID: <4B0AEF4E.8070005@gmail.com> Date: Mon, 23 Nov 2009 21:23:42 +0100 From: Roel Kluin User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.4pre) Gecko/20091014 Fedora/3.0-2.8.b4.fc11 Thunderbird/3.0b4 MIME-Version: 1.0 To: Andrew Morton , LKML Subject: [PATCH] vt: Don't exceed max_font_size on copy in con_font_get() Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org font.data is kmallocd with max_font_size (defined 65536). Below occurs a copy_to_user with `c' as a size argument. Ensure we don't copy too much. Signed-off-by: Roel Kluin --- drivers/char/vt.c | 4 ++++ 1 files changed, 4 insertions(+), 0 deletions(-) If it is possible for c to be greater than 65536 then I think we may need this. Correct? diff --git a/drivers/char/vt.c b/drivers/char/vt.c index 0c80c68..045af83 100644 --- a/drivers/char/vt.c +++ b/drivers/char/vt.c @@ -3861,6 +3861,10 @@ static int con_font_get(struct vc_data *vc, struct console_font_op *op) goto out; c = (font.width+7)/8 * 32 * font.charcount; + if (c > max_font_size) { + rc = -EINVAL; + goto out; + } if (op->data && font.charcount > op->charcount) rc = -ENOSPC;