Re: kern/41877: PaX ASLR reduces available stack size

[Pierre Pronchery <khorben%defora.org@localhost>]

The following reply was made to PR kern/41877; it has been noted by GNATS.

From: Pierre Pronchery <khorben%defora.org@localhost>
To: gnats-bugs%netbsd.org@localhost
Cc: 
Subject: Re: kern/41877: PaX ASLR reduces available stack size
Date: Wed, 4 Jan 2012 02:00:40 +0100

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                        Hi,
 
 testing Manuel's program in this problem report seems to work reliably
 for me with the following change, which reduced the memory allocation on
 the stack by only 8 KB:
 #define ALLOCASZ (2048 * 1024 - 4096 * 5)
 
 This is true both on NetBSD/amd64 5.99.58 (from approximately December
 1st 2011) and on NetBSD/amd64 5.1_STABLE (tracking the netbsd-5 branch).
 
 In both cases I have set the stack size to the same value:
 $ ulimit -s 2048
 $ ulimit -s
 2048
 
 Setting ALLOCASZ to be bigger by just 4 KB triggers crashes after one to
 three attempts. I suppose that this behavior is as expected though;
 could it be that the modification pushed in kern/43773 fixed this report
 as well?
 
 HTH,
 --=20
 khorben
 
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