bugtraq - Re: gcc 4.1 bug miscompiles pointer range checks, may place you at risk

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-next>] [day] [month] [year] [list]

Message-ID: <20060503072109.5116.qmail@securityfocus.com>
Date: 3 May 2006 07:21:09 -0000
From: leonleon77@...mail.com
To: bugtraq@...urityfocus.com
Subject: Re: gcc 4.1 bug miscompiles pointer range checks, may place you
 at risk


perhaps instead of "c + len > c" being the test of pointer wraparound, one may use the following (if there is a desire to use pointer-based arithmetic)...

#define MAXPTR (char *)0xffffffff // this would differ on 64 bit systems

if (MAXPTR - c < len)
{
// we have a pointer wraparound...
}