From patchwork Thu Dec 7 10:31:50 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florian Weimer X-Patchwork-Id: 81637 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id C2A5D385B515 for ; Thu, 7 Dec 2023 10:32:21 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id 50A28386183B for ; Thu, 7 Dec 2023 10:31:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 50A28386183B Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=redhat.com ARC-Filter: OpenARC Filter v1.0.0 sourceware.org 50A28386183B Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=170.10.129.124 ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701945116; cv=none; b=nT/Wi6qgnpMOGVR3K3kH76L8kbmL7JsY8vtA8x+yP1rA7RfOWKv6ihI4USoGLLdjQIHr4aYVlPXQWhyVeAnQaAuvEwIzKAWzV+OG8++/RwIGrrRb1XsGiRRYSRuuC8gcR7dG/u/W4DP5ZNiruSvongWhSFF7Z2XPdnCgDe6BQAI= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1701945116; c=relaxed/simple; bh=DhGtVKrIDfWuWZiYjFVw5/bwUrj5oxrivYAdCGSURT0=; h=DKIM-Signature:From:To:Subject:Message-ID:Date:MIME-Version; b=GKZ02nP/PjOmfhSfhzo5BITBa8rdIyd6Lvmp+xqbFfzoBKkIr1599T7HrSk4VDgXi0+A/n/Cv8mAxIVXwZIcQJxHB1NNKhOqQcywTThHjjyAlJumlH3nQ6ZpmxMyCv8O19EjM0zMLRlWYhVNuvuaI4ENtVrGxcMT2jlrPsWCzRg= ARC-Authentication-Results: i=1; server2.sourceware.org DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1701945114; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=iUuX6VVBLyQra0/NGM0k1cnLfINds327LHaOp1QnArQ=; b=VxZrmkL0UNqzpilkXQIrqFbJirezIJqBzX+sY6IN5+XahI+nUCnbuV2MVhDMZASZxmnr5W PlIi4TzViVHp5OsCh2q/BIAXtFipt+q8tQx6sW0ZpTvpfPe7bU/7DZuyxRh2+mY7w5H2yS 4WsJNL+9dZqLlcBdUH/O87xnv4iAhsg= Received: from mimecast-mx02.redhat.com (mx-ext.redhat.com [66.187.233.73]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-187-QEgjL81nOtqiTHgFaKbAvw-1; Thu, 07 Dec 2023 05:31:53 -0500 X-MC-Unique: QEgjL81nOtqiTHgFaKbAvw-1 Received: from smtp.corp.redhat.com (int-mx09.intmail.prod.int.rdu2.redhat.com [10.11.54.9]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 4C04D3C100B5 for ; Thu, 7 Dec 2023 10:31:53 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.131]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E3700492BC6 for ; Thu, 7 Dec 2023 10:31:52 +0000 (UTC) From: Florian Weimer To: libc-alpha@sourceware.org Subject: [PATCH v3 12/32] elf: Move __rtld_malloc_init_stubs call into _dl_start_final In-Reply-To: Message-ID: <6eab32e6135995d90fe989dd763c627cc9e8d9f5.1701944612.git.fweimer@redhat.com> References: X-From-Line: 6eab32e6135995d90fe989dd763c627cc9e8d9f5 Mon Sep 17 00:00:00 2001 Date: Thu, 07 Dec 2023 11:31:50 +0100 User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.3 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 3.4.1 on 10.11.54.9 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com X-Spam-Status: No, score=-10.8 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Calling an extern function in a different translation unit before self-relocation is brittle. The compiler may load the address at an earlier point in _dl_start, before self-relocation. In _dl_start_final, the call is behidn a compiler barrier, so this cannot happen. --- elf/rtld.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/elf/rtld.c b/elf/rtld.c index a00a8d9d0f..05cbcee24a 100644 --- a/elf/rtld.c +++ b/elf/rtld.c @@ -452,6 +452,8 @@ _dl_start_final (void *arg, struct dl_start_final_info *info) { ElfW(Addr) start_addr; + __rtld_malloc_init_stubs (); + /* Do not use an initializer for these members because it would interfere with __rtld_static_init. */ GLRO (dl_find_object) = &_dl_find_object; @@ -574,8 +576,6 @@ _dl_start (void *arg) function, that way the compiler cannot put accesses to the GOT before ELF_DYNAMIC_RELOCATE. */ - __rtld_malloc_init_stubs (); - #ifdef DONT_USE_BOOTSTRAP_MAP return _dl_start_final (arg); #else