Bugtraq: Re: Calife heap corrupt / potential local root exploit

[Carson Gaspar <carson+bugtraq () taltos org>]

--On Friday, February 27, 2004 16:49:34 +0000 Ollivier Robert 
<roberto () keltia freenix fr> wrote:
> In-Reply-To: <20040227091921.26210.qmail () www securityfocus com>
>
> >            pt_pass = (char *) getpass ("Password:");
> >            memset (user_pass, '\0', l_size);
> >            strcpy (user_pass, pt_pass); // <- BAD CODE
> I could have used strlcpy but I assumed (and my reading of the FreeBSD
> source code confirm it) that getpass(3) was doing the size check.
This is why you shouldn't make such assumptions. Never assume someone else 
validated your input. If you want to write secure code, assume every 
function is under attack from every other function, because someday someone 
will change the program flow, bypassing your carefully crafted validation 
function and passing garbage to your insecure code. Outsourcing your 
validation to other code is the software equivalent of the hard outside / 
soft tasty center security model.
--
Carson