Vulnerability Development mailing list archives
Re: N00b questions :\
From: "Janus N." Tøndering <janus () bananus dk>
Date: 25 May 2003 03:28:10 +0200
On Sun, 2003-05-25 at 03:42, northern snowfall wrote:
GCC sometimes allocates more memory for each variable on the stack than is actually requested. I have no idea exactly why and what is does -- but I assume it is some small optimization.FYI, compilers (are supposed to) align memory to the requirement of the underlying architecture. Most processors will throw an alignment_error exception if an opcode attempts to pass an unaligned address to it. This is done simply by padding the stack so that each auto variable is given a properly aligned memory address.
Oh yeah ... true. But isn't this 32-bit on the ia32? GCC 3.x allocates way more than is neccessary to have it aligned. The vulndev-2 buffer of 90 bytes should be 92 right? But gcc allocates 108. Why does it do this extra padding then? Janus -- Janus N. Tøndering <janus () bananus dk>
Current thread:
- Re: [Vuln-dev Challenge] Challenge #2, (continued)
- Re: [Vuln-dev Challenge] Challenge #2 Diode Trnasistor (May 26)
- Re: [Vuln-dev Challenge] Challenge #2 Janus N. (May 26)
- Re: [Vuln-dev Challenge] Challenge #2 Robert Hogan (May 30)
- Re: [Vuln-dev Challenge] Challenge #2 Janus N. (May 30)
- Re: [Vuln-dev Challenge] Challenge #2 Diode Trnasistor (May 26)
- Gera's Insecure Programing abo7 sin (May 30)
- N00b questions :\ Diode Trnasistor (May 24)
- Re: N00b questions :\ Janus N. (May 24)
- Re: N00b questions :\ northern snowfall (May 24)
- Re: N00b questions :\ Janus N. (May 24)
- Re: N00b questions :\ northern snowfall (May 24)
- Re: N00b questions :\ Diode Trnasistor (May 25)