From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <libc-alpha-return-107624-listarch-libc-alpha=sources.redhat.com@sourceware.org>
Received: (qmail 81238 invoked by alias); 2 Dec 2019 16:07:14 -0000
Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <libc-alpha.sourceware.org>
List-Subscribe: <mailto:libc-alpha-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/libc-alpha/>
List-Post: <mailto:libc-alpha@sourceware.org>
List-Help: <mailto:libc-alpha-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: libc-alpha-owner@sourceware.org
Received: (qmail 81230 invoked by uid 89); 2 Dec 2019 16:07:14 -0000
Authentication-Results: sourceware.org; auth=none
X-Spam-SWARE-Status: No, score=-6.0 required=5.0 tests=AWL,BAYES_00,SPF_PASS autolearn=ham version=3.3.1 spammy=activating, gained
X-HELO: us-smtp-delivery-1.mimecast.com
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com;
	s=mimecast20190719; t=1575302831;
	h=from:from:reply-to:subject:subject:date:date:message-id:message-id:
	 to:to:cc:mime-version:mime-version:content-type:content-type:
	 content-transfer-encoding:content-transfer-encoding:
	 in-reply-to:in-reply-to:references:references;
	bh=03SxwiHQqgWlrOGwhtXED8ycXkqFfCvXFDDvP5VmvZE=;
	b=Vf0/lA+R/6dyIFXqWkynSF2JVHbZFHs0aOPq4hUJWUdFGtP3wwFgHsld7n6pjpXyeW2+ze
	l6UDV3XFHePpH1He9BGYbC4cZhyLjUDG3Wkv8i/SmrCiBDvVeObiSTpDj8cmaAyJlEBAfZ
	WwP0ODfrqJx+Mq3CQpUBNi0SPQdCDbE=
From: Florian Weimer <fweimer@redhat.com>
To: libc-alpha@sourceware.org
Subject: Re: [review v3] Remove all loaded objects if dlopen fails, ignoring NODELETE [BZ #20839]
References: <gerrit.1572549639000.Ib2a3d86af6f92d75baca65431d74783ee0dbc292@gnutoolchain-gerrit.osci.io>
	<20191115160205.9EEC928171@gnutoolchain-gerrit.osci.io>
Date: Mon, 02 Dec 2019 16:07:00 -0000
In-Reply-To: <20191115160205.9EEC928171@gnutoolchain-gerrit.osci.io> (Florian
	Weimer's message of "Fri, 15 Nov 2019 11:02:04 -0500")
Message-ID: <871rtmyams.fsf@oldenburg2.str.redhat.com>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux)
MIME-Version: 1.0
X-Mimecast-Spam-Score: 0
Content-Type: text/plain
Content-Transfer-Encoding: quoted-printable
X-SW-Source: 2019-12/txt/msg00056.txt.bz2

* Florian Weimer:

> +/* Mark the objects as NODELETE if required.  This is delayed until
> +   after dlopen failure is not possible, so that _dl_close can clean
> +   up objects if necessary.  */
> +static void
> +activate_nodelete (struct link_map *new, int mode)
> +{
> +  if (mode & RTLD_NODELETE || new->l_nodelete =3D=3D link_map_nodelete_p=
ending)
> +    {
> +      if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES))
> +	_dl_debug_printf ("activating NODELETE for %s [%lu]\n",
> +			  new->l_name, new->l_ns);
> +      new->l_nodelete =3D link_map_nodelete_active;
> +    }
> +
> +  for (unsigned int i =3D 0; i < new->l_searchlist.r_nlist; ++i)
> +    {
> +      struct link_map *imap =3D new->l_searchlist.r_list[i];
> +      if (imap->l_nodelete =3D=3D link_map_nodelete_pending)
> +	{
> +	  if (__glibc_unlikely (GLRO (dl_debug_mask) & DL_DEBUG_FILES))
> +	    _dl_debug_printf ("activating NODELETE for %s [%lu]\n",
> +			      imap->l_name, imap->l_ns);
> +
> +	  /* Only new objects should have set
> +	     link_map_nodelete_pending.  Existing objects should not
> +	     have gained any new dependencies and therefore cannot
> +	     reach NODELETE status.  */
> +	  assert (!imap->l_init_called || imap->l_type !=3D lt_loaded);

This assert is incorrect because the NODELETE markers actually go in the
other direction (from new loaded libraries to their dependencies).

I still need to write tests for this.  But I can submit a patch for the
removal of the assert immediately, if so desired.

Thanks,
Florian