From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([208.118.235.92]:34448)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <agraf@suse.de>) id 1SeiJU-0000VO-1H
	for qemu-devel@nongnu.org; Wed, 13 Jun 2012 03:48:25 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <agraf@suse.de>) id 1SeiJP-00032J-Oc
	for qemu-devel@nongnu.org; Wed, 13 Jun 2012 03:48:23 -0400
Received: from cantor2.suse.de ([195.135.220.15]:57042 helo=mx2.suse.de)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <agraf@suse.de>) id 1SeiJP-00031X-I3
	for qemu-devel@nongnu.org; Wed, 13 Jun 2012 03:48:19 -0400
Message-ID: <4FD846E8.5010601@suse.de>
Date: Wed, 13 Jun 2012 09:53:12 +0200
From: Alexander Graf <agraf@suse.de>
MIME-Version: 1.0
References: <1338984323-21914-1-git-send-email-jfrei@de.ibm.com>	
	<1338984323-21914-8-git-send-email-jfrei@de.ibm.com>	
	<4FD72D75.4050907@suse.de>
	<1339572458.3591.34.camel@BR8HFPP0.boeblingen.de.ibm.com>
In-Reply-To: <1339572458.3591.34.camel@BR8HFPP0.boeblingen.de.ibm.com>
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH 7/8] s390: Add SCLP vt220 console support
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Heinz Graalfs <graalfs@linux.vnet.ibm.com>
Cc: Jens Freimann <jfrei@de.ibm.com>, Cornelia Huck <cornelia.huck@de.ibm.com>, Jens Freimann <jfrei@linux.vnet.ibm.com>, qemu-devel <qemu-devel@nongnu.org>

Heinz Graalfs wrote:
> On Tue, 2012-06-12 at 13:52 +0200, Alexander Graf wrote:
>   
>> On 06/06/2012 02:05 PM, Jens Freimann wrote:
>>     
>>> From: Heinz Graalfs<graalfs@linux.vnet.ibm.com>
>>>
>>>       

[...]

>>> +static void chr_read_vt220(void *opaque, const uint8_t *buf, int size)
>>> +{
>>> +    char *offset;
>>> +
>>> +    if (!sclp_console_data_vt220) {
>>> +        size_buffer = 2 * size;
>>>       
>> Why 2*?
>>
>>     
>
> OK, will change to exact size plus 1 for trailing 0
>   

This happens in more than one place btw :).

>
>   
>>> +        free(sclp_console_data_vt220);
>>> +        size_buffer = 2 * size;
>>> +        sclp_console_data_vt220 = malloc(size_buffer);
>>> +    }
>>> +    offset = sclp_console_data_vt220;
>>> +    if (offset) {
>>> +        memcpy(offset, buf, size);
>>> +        offset += size;
>>> +        *offset = '\0';
>>>       
>> How do you know you're not out of bounds?
>>
>>     
> OK, size + 1
>   

I was more thinking of the memcpy(some_variable, ..., n) where you never
check if available_space(some_variable) > n, no?


Alex