linux-kernel - Re: 2.6.23-rc8-mm1 -- powerpc link failure

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20070927193123.GC1847@uranus.ravnborg.org>
Date:	Thu, 27 Sep 2007 21:31:23 +0200
From:	Sam Ravnborg <sam@...nborg.org>
To:	Andrew Morton <akpm@...ux-foundation.org>
Cc:	Jiri Kosina <jkosina@...e.cz>, Andy Whitcroft <apw@...dowen.org>,
	Franck Bui-Huu <vagabon.xyz@...il.com>,
	linux-kernel@...r.kernel.org,
	Kamalesh Babulal <kamalesh@...ux.vnet.ibm.com>
Subject: Re: 2.6.23-rc8-mm1 -- powerpc link failure

On Thu, Sep 27, 2007 at 10:13:42AM -0700, Andrew Morton wrote:
> On Thu, 27 Sep 2007 14:13:21 +0200 (CEST) Jiri Kosina <jkosina@...e.cz> wrote:
> 
> > On Thu, 27 Sep 2007, Andy Whitcroft wrote:
> > 
> > > Ok, this problem seems to still persist in 2.6.23-rc8-mm2.  It seems we 
> > > have three options from here:
> > > 1) update the compiler support list to exclude these compilers, or
> > > 2) back this change out, or
> > > 3) switch to the version not using __weak.
> > > The latter seems to be the least intrusive change.  As no-one closer to 
> > > the problem is stepping up to make the decision I will propose we go 
> > > with the third option here.
> > 
> > Andrew,
> > 
> > if you agree with Andy that we should support compilers that don't work 
> > with __weak, please drop i386-and-x86_64-randomize-brk.patch and replace 
> > it with the one below instead (this has been already posted at 
> > http://lkml.org/lkml/2007/8/31/113). Thanks.
> > 
> 
> We have quite a few instances of __weak in there.  What is special about
> this one?

The bug we trigger is an ld bug - not a compiler bug.
What happens is that we have the same function defined weak twice.
In fs/ we include binfmt_elf.o in the build because
CONFIG_BINFMT_ELF is set.
And in arch/powerpc/kernel/binfmt_elf32.c:
we do an: #include "../../../fs/binfmt_elf.c"

Without actually trying it out I assume we trigger the ld bug
because we define the same weak function twice.

And this is a non-typical situation.

	Sam
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/