Subject: Re: SA/pthread syscall versioning
To: Christos Zoulas <>
From: Matt Thomas <>
List: tech-kern
Date: 12/11/2003 16:17:52
On Dec 11, 2003, at 11:40 AM, Christos Zoulas wrote:

> In article <>,
> Matt Thomas <> wrote:
>> On Dec 11, 2003, at 8:55 AM, Christos Zoulas wrote:
>>> BTW, this is the case [leaking kernel memory info] in many of the
>>> siginfo
>>> machdep.c files (sparc,sparc64,vax, etc.) It did not seem important 
>>> at
>>> the time, but maybe we should bring it up for discussion again.
>> The vax implementation (and powerpc) does not leak kernel memory info.
>> However, it will leave portions of the siginfo_t that are not
>> used/overlayed
>> by ksiginfo_t unchanged.  That is not a kernel memory leak.
> Yes, that's it. It leaves uninitialized userland memory [stack]. Things
> like purify will bitch at it... I was wrong about the kernel leak.

It's not uninitialized.  Initially, it was set to all-0 and may now 
previous stack contents.  I doubt purify would complain since it was not
able to control its creation.  I see no reason to copy data to the user
stack that the user won't be looking at.  It's just wasteful.
Matt Thomas                     email:
3am Software Foundry              www:
Cupertino, CA              disclaimer: I avow all knowledge of this