[11696] in bugtraq
Re: Stack Shield: defending from "stack smashing" attacks
daemon@ATHENA.MIT.EDU (Chris Keane)
Sat Sep 4 11:07:31 1999
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Message-Id: <19990902162436.1.11771.qmail@userpc16.comlab.ox.ac.uk>
Date: Thu, 2 Sep 1999 16:24:36 +0100
Reply-To: Chris Keane <Chris.Keane@COMLAB.OX.AC.UK>
From: Chris Keane <Chris.Keane@COMLAB.OX.AC.UK>
X-To: BUGTRAQ@securityfocus.com
To: BUGTRAQ@SECURITYFOCUS.COM
In-Reply-To: <37CC0D31.55882224@cse.ogi.edu> (Tue, 31 Aug 1999 17:13:21 -0000)
>>>>> On Tue, 31 Aug 1999, "CC" = Crispin Cowan wrote:
+> So, why would one use the approach of saving the return address on
+> another stack, instead of patching the stack itself, like StackGuard?
+> The only reason I can imagine, is that one does not want to change the
+> stack layout. The benefit of not changing the stack layout, is that
+> you can do the change outside of the compiler.
CC> Another major advantage is that gdb continues to work. The
CC> StackGuard method fails for all programs that introspect the stack,
CC> gdb being the major example.
And presumably it would mean you could compile kernels with it, which also
fails with StackGuard (for Linux, at least).
Cheers,
Chris.
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