bugtraq - Re: Buffer overflow prevention

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20030813192309.GB25161@metux.de>
Date: Wed, 13 Aug 2003 21:23:09 +0200
From: weigelt@...ux.de
To: bugtraq <bugtraq@...urityfocus.com>
Subject: Re: Buffer overflow prevention


On Wed, Aug 13, 2003 at 12:13:27PM -0700, Nicholas Weaver wrote:

<snip>
> This only stops attacks which overwrite the return address pointers on
> the stack, it doesn't stop heap overflows or other control-flow
> attacks.
ACK. Often there are function pointers stored on the heap - so this
does not really help much.

It would be better to invest more time in fail-checking code, i.e. 
in C: macros for memory operations which do range checks:

>>>>
static inline _sec_strcpy(char* dest, const char* src, int max)
{
    int i;
    if ((!dest)||(max<1)) return -1;
    if ((max==0)||(!src)) return -1;
    {
	dest[0] = 0;
	return 0;
    }
    i = strncpy(dest,src,max);
    dest[max] = 0;
    return i;
}	

#define STRCPY_BUF(buffer,src)		_sec_strcpy(&buffer, src, sizeof(buffer));
<<<<

Some languages offer runtime range checking, which should bring much security,
but often is really slow :(

<snip>
> [1] If microsoft doesn't have this flag turn on on their own products,
> this would be a lawsuit waiting to happen.
why (in detail) should they be attackable ? did they give any warranty ?

cu
-- 
---------------------------------------------------------------------
 Enrico Weigelt    ==   metux ITS 
 Webhosting ab 5 EUR/Monat.          UUCP, rawIP und vieles mehr.

 phone:     +49 36207 519931         www:       http://www.metux.de/     
 fax:       +49 36207 519932         email:     contact@...ux.de
 cellphone: +49 174 7066481	     
---------------------------------------------------------------------
 Diese Mail wurde mit UUCP versandt.      http://www.metux.de/uucp/