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Date: Wed, 12 Jan 2022 11:41:43 +0100
From: Corinna Vinschen <corinna-cygwin@cygwin.com>
To: cygwin@cygwin.com
Subject: Re: posix_spawn issues on i686
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On Jan 11 16:08, Ken Brown wrote:
> On 1/11/2022 1:45 PM, Jeremy Drake via Cygwin wrote:
> > Sorry, I am not subscribed to the list so don't have the message to reply
> > to for threading purposes, but attached please find a C reproducer that
> > works on x86_64 but fails on i686.  The particular issue seems to be the
> > POSIX_SPAWN_RESETIDS flag - not setting that allows i686 to succeed too.

Thanks for the STC, Jeremy!

> I don't have time to check this carefully, but it looks to me like the
> problem is that process_spawnattr calls setegid and seteuid instead of
> setegid32 and seteuid32.  This causes truncation of the gid and uid.

You're right.  Additionally the calls to getgid and getuid have to use
the internal getgid32 and getuid32 functions.

I'll apply a fix.


Thanks guys!
Corinna

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