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=ham 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 58C07C4CED1 for ; Thu, 3 Oct 2019 16:50:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 23BC82086A for ; Thu, 3 Oct 2019 16:50:29 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570121429; bh=DLaN/Hdn1G8Wec4gNiumUQAwHA3S+1L14RNLvVUb3Ow=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=fVk8bNgAe5Po2yicHV/lpERkcE11p4JgVfENh31246iMU6cFPkdsoNW03c7GH2LAE BQBluJ0FxT1qP7dngXNlIJCTlR3bL07WYCirEQzA5CoNehwnOLIFkZ7A/l1PL1xZX3 LlThPLRi+4MR4Hla89RycaF9tiBsxOxduj41o6W4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2392932AbfJCQu2 (ORCPT ); Thu, 3 Oct 2019 12:50:28 -0400 Received: from mail.kernel.org ([198.145.29.99]:37568 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2392586AbfJCQu1 (ORCPT ); Thu, 3 Oct 2019 12:50:27 -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 165D82070B; Thu, 3 Oct 2019 16:50:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1570121426; bh=DLaN/Hdn1G8Wec4gNiumUQAwHA3S+1L14RNLvVUb3Ow=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ATObzNxbdGXlvGuzDdU+M8M+pfzvxwp6YoKdxmIWsd79x08OcdiyGtOh8m9S9B9pH ETQYAclSpa7uIWeE+QQyL81Ps+AP9fEz2AOaHQ2yThUw61IQjt3/yLXU8YqdZnWt2O kmSXaTwWZ0m7CrsRTi36PASqGLZkyy717Nz0MRQw= 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 5.3 275/344] binfmt_elf: Do not move brk for INTERP-less ET_EXEC Date: Thu, 3 Oct 2019 17:54:00 +0200 Message-Id: <20191003154607.279467431@linuxfoundation.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191003154540.062170222@linuxfoundation.org> References: <20191003154540.062170222@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 @@ -1141,7 +1141,8 @@ out_free_interp: * (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;