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Wireshark-dev: Re: [Wireshark-dev] [patch] address_to_str_buf not checking available buffer len

From: Andrej Mikus <wireshark-dev@xxxxxxxx>
Date: Wed, 31 Jan 2007 16:24:29 +0100
Accepted or not, I needed to do something to get my working copy
compiled. Attached is the patch if you like to use it.

Thanks
Andrej

On Wed, 31.Jan.07 12:29:30 +0100, Andrej Mikus wrote:
> On Mon, 29.Jan.07 12:49:00 -0800, Gerald Combs wrote:
> > Andrej Mikus wrote:
> > 
> > > In file to_str.c I notice function address_to_str_buf that takes buf_len
> > > as argument, but does not use it for IPv4 and IPv6 addresses:
> > > 
> > Unfortunately, there wasn't a mechanism to ensure that the buffer was
> > big enough.  I've checked in a change (r20607) that should fix this.  It
> > looks like this could potentially affect the ISUP statistics, so I'll
> > add it to the advisory list for 0.99.5.
> 
> I was planning to propose a patch already (attached), so this allowed me
> to see how Subversion handles conflicts :-)
> 
> IMO, the function should return an error string instead of cowardly
> bailing out with an empty string.
> 
> inet_ntop does the latter by default, so it does not need any additional
> check, just passing buf_len instead of INET6_ADDRSTRLEN.
> 
> At the other side I like the check you made into ip_to_str_buf.
> 
> My proposal would be to combine the patches and use MAX_IP_STR_LEN,
> and approach below for both IPv4 and IPv6 in address_to_str_buf.
> 
>    case AT_IPv6:
> +<<<<<<< .mine
> +    if ( inet_ntop(AF_INET6, addr->data, buf, buf_len) == NULL ) /* Returns NULL if no space and does not touch buf */
> +       g_snprintf ( buf, buf_len, "@@@@@@@@" );                 /* Let the unexpected value alert user */
> 
> If accepted, I am ready to supply a patch on top of current rev .r20649
> Let me know pls.
> 
> Andrej


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