From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <sourceware-bugzilla@sourceware.org>
Received: by sourceware.org (Postfix, from userid 48)
	id 791F93872219; Wed, 14 Dec 2022 00:14:58 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 791F93872219
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org;
	s=default; t=1670976898;
	bh=eoEbovzojfgdvP/oDtS8jXgDFQ6O1KvsqPUn/Gszme4=;
	h=From:To:Subject:Date:In-Reply-To:References:From;
	b=GxuubCVxAkgCjK28qwAO05ZubeTmKJZ7m8MAriNyQcMZQV978pMsooDUh29fJdfVR
	 xXV+ec2tqJ+YVtrO/+hUfColBPzIS3L2YydUKIqCIgmrTxCO4A+f3J7fticZ++Jsbc
	 wt7Ie1p5PA+NR9Hl96erYgDbVJZyP/sYLhxzCIP0=
From: "goldstein.w.n at gmail dot com" <sourceware-bugzilla@sourceware.org>
To: glibc-bugs@sourceware.org
Subject: [Bug libc/29863] Segmentation fault in memcmp-sse2.S if memory
 contents can concurrently change
Date: Wed, 14 Dec 2022 00:14:57 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: glibc
X-Bugzilla-Component: libc
X-Bugzilla-Version: 2.36
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: goldstein.w.n at gmail dot com
X-Bugzilla-Status: UNCONFIRMED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-29863-131-fjVuhUcauZ@http.sourceware.org/bugzilla/>
In-Reply-To: <bug-29863-131@http.sourceware.org/bugzilla/>
References: <bug-29863-131@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
List-Id: <glibc-bugs.sourceware.org>

https://sourceware.org/bugzilla/show_bug.cgi?id=3D29863

--- Comment #16 from Noah Goldstein <goldstein.w.n at gmail dot com> ---
(In reply to Narayanan Iyer from comment #14)
> (In reply to Noah Goldstein from comment #13)
> >=20
> > Can you test the following dif:
> > ```
> > @@ -308,7 +308,7 @@ L(ret_nonzero_vec_end_0):
> >   setg %dl
> >   leal -1(%rdx, %rdx), %eax
> >  #  else
> > - addl %edx, %eax
> > + addq %rdx, %rax
> >   movzbl (VEC_SIZE * -1 + SIZE_OFFSET)(%rsi, %rax), %ecx
> >   movzbl (VEC_SIZE * -1 + SIZE_OFFSET)(%rdi, %rax), %eax
> >   subl %ecx, %eax
> >=20
> > ```
> >=20
> > If that fixes things I'm okay making the change.
> >=20
> > I'm opposed to explicitly supporting it, but am happy
> > to try and make this failure from the unsupported
> > usage less dramatic.
>=20
> This change sounds much better.
>=20
> Is there a url that describes how to build glibc from source and use it in
> my application?

Posted a patch which should fix the issue.

--=20
You are receiving this mail because:
You are on the CC list for the bug.=