Bugtraq mailing list archives
Re: [ANNOUNCE] glibc heap protection patch
From: William Robertson <wkr () cs ucsb edu>
Date: Wed, 3 Dec 2003 14:25:09 -0800
On Dec 03, 2003, at 05:01, Stefan Esser wrote:
The last time I checked there was no such check in the unlink macro (no matter if debug mode or not).
Ah, ok, I see what you meant. The check I was referring to wasn't in the unlink macro, but in one of dlmalloc's debugging routines. If you move it into unlink itself, then it does indeed prevent all unlink exploits, as you say. I agree that a combination of the two techniques would theoretically be stronger than each on its own, but I also believe that using properly randomized magic numbers in practice guarantees that chunk headers cannot be tampered with. However, you do get a lot for this simple check, so it makes sense to include it.
Thanks for pointing that out.
Stefan Esser
-- William Robertson Reliable Software Group, UC Santa Barbara http://www.cs.ucsb.edu/~wkr/
Current thread:
- [ANNOUNCE] glibc heap protection patch William Robertson (Dec 01)
- Re: [ANNOUNCE] glibc heap protection patch Stefan Esser (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch Stefan Esser (Dec 03)
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 03)
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch Stefan Esser (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch Eugene Tsyrklevich (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 02)
- Re: [ANNOUNCE] glibc heap protection patch Han Boetes (Dec 03)
- Re: [ANNOUNCE] glibc heap protection patch Adam Shostack (Dec 04)
- Re: [ANNOUNCE] glibc heap protection patch Jim Knoble (Dec 04)
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 02)
- Message not available
- Re: [ANNOUNCE] glibc heap protection patch William Robertson (Dec 04)
- <Possible follow-ups>
- Re: [ANNOUNCE] glibc heap protection patch xenophi1e (Dec 03)
- Re: [ANNOUNCE] glibc heap protection patch Stefan Esser (Dec 04)
- Re: [ANNOUNCE] glibc heap protection patch Troed SĂ„ngberg (Dec 04)
- Re: [ANNOUNCE] glibc heap protection patch Stefan Esser (Dec 04)
- Re: [ANNOUNCE] glibc heap protection patch Marco Ivaldi (Dec 04)