This is the mail archive of the
libc-alpha@sourceware.org
mailing list for the glibc project.
Re: Fix hppa/ia64/microblaze executable stack default (bug 22156)
- From: Carlos O'Donell <carlos at redhat dot com>
- To: Joseph Myers <joseph at codesourcery dot com>, libc-alpha at sourceware dot org, dave dot anglin at bell dot net
- Cc: vapier at gentoo dot org
- Date: Tue, 19 Sep 2017 07:56:06 -0600
- Subject: Re: Fix hppa/ia64/microblaze executable stack default (bug 22156)
- Authentication-results: sourceware.org; auth=none
- References: <alpine.DEB.2.20.1709191345040.2962@digraph.polyomino.org.uk>
On 09/19/2017 07:46 AM, Joseph Myers wrote:
> As per https://gcc.gnu.org/ml/gcc-patches/2017-09/msg01220.html hppa,
> ia64 and microblaze default to non-executable stacks in the Linux
> kernel. glibc however defines DEFAULT_STACK_PERMS to include PF_X for
> those architectures, meaning (a) elf/check-execstack fails and (b)
> (from code inspection, not tested, but this is why I think this is a
> user-visible bug) thread stacks are unnecessarily mapped with execute
> permission. This patch fixes the DEFAULT_STACK_PERMS definitions in
> question.
>
> Tested (compilation only) with build-many-glibcs.py for those
> configurations. This fixes the check-execstack failure (hppa still
> has a check-textrel failure as the only remaining issue stopping that
> architecture having clean build-many-glibcs.py results; hopefully
> architecture maintainers can help resolve that).
I thought that PF_X was required for hppa because there was still code
generated by gcc for hppa that needed it? Otherwise *I* would have
removed it when I did the PT_GNU_STACK cleanups for all the arches.
Dave is the best positioned to answer this question.
--
Cheers,
Carlos.