From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E486BECE58B for ; Thu, 3 Oct 2019 17:29:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B2D0620830 for ; Thu, 3 Oct 2019 17:29:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570123756; bh=cJIv5/qNCRfpgoyHBGiQr4dN6PXNAlmJtOYktcQtAUY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=CPygZNSgV5ZGHn7d1BmSfuxCv86hqyb8iRrN3LTQ9e3j3vCDtAIk3ldmDJaQdoF9S cnZlFQqPrkDrkj/rT5E9YIkcvFwq2zy73bNj4cK2BWgYBQssJuoVoEsCKcBGs4mmLz BNfHePRXAIABLILoNhL1j9fpBe85a0oBkDpP3S9s= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732164AbfJCQNF (ORCPT ); Thu, 3 Oct 2019 12:13:05 -0400 Received: from mail.kernel.org ([198.145.29.99]:35566 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388195AbfJCQNA (ORCPT ); Thu, 3 Oct 2019 12:13:00 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 9781720700; Thu, 3 Oct 2019 16:12:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570119179; bh=cJIv5/qNCRfpgoyHBGiQr4dN6PXNAlmJtOYktcQtAUY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lAO/3TiOWvlDNPXdhetIIyqNslEY71gdEYg6kYmW1A5WUyLoqLlkfrzaNMRLp+/oC 4+60bGmZGO6IrKXzTHOODdQGuCsmpf/dhNXZm1PXa39EaCoyjN7mUufp9aUJBNnNwV 3rECLUEFBw5zE6zHkMYc8Aopanoxc/JdgekgQgKY= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Kees Cook , Linus Torvalds , Richard Kojedzinszky Subject: [PATCH 4.14 154/185] binfmt_elf: Do not move brk for INTERP-less ET_EXEC Date: Thu, 3 Oct 2019 17:53:52 +0200 Message-Id: <20191003154514.087761098@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154437.541662648@linuxfoundation.org> References: <20191003154437.541662648@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Kees Cook commit 7be3cb019db1cbd5fd5ffe6d64a23fefa4b6f229 upstream. When brk was moved for binaries without an interpreter, it should have been limited to ET_DYN only. In other words, the special case was an ET_DYN that lacks an INTERP, not just an executable that lacks INTERP. The bug manifested for giant static executables, where the brk would end up in the middle of the text area on 32-bit architectures. Reported-and-tested-by: Richard Kojedzinszky Fixes: bbdc6076d2e5 ("binfmt_elf: move brk out of mmap when doing direct loader exec") Cc: stable@vger.kernel.org Signed-off-by: Kees Cook Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- fs/binfmt_elf.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -1123,7 +1123,8 @@ static int load_elf_binary(struct linux_ * (since it grows up, and may collide early with the stack * growing down), and into the unused ELF_ET_DYN_BASE region. */ - if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) && !interpreter) + if (IS_ENABLED(CONFIG_ARCH_HAS_ELF_RANDOMIZE) && + loc->elf_ex.e_type == ET_DYN && !interpreter) current->mm->brk = current->mm->start_brk = ELF_ET_DYN_BASE;