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=-8.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,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 49DA4C48BE3 for ; Thu, 20 Jun 2019 17:59:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 2A3A721530 for ; Thu, 20 Jun 2019 17:59:37 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561053577; bh=hgh0MmmjlfsY1C3iEfMNRRPgfNuNj5U04xYQ2Qpe9fY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=zIMVKrdv/1wR6p2N6JZShJE3q0+8h5MrSThnr7X1gIywumKDFf7MytTaBGGsitMij bcgkUbAgYxkUyH1y40ggcLs8vBneLYGA9L7GfdGz5GQ3oM2kXQkmZaxJTIUSXLJKGZ nvEdiIWk0k3qgrvDbJW2x25wxCtiuUDnIReFsWtU= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726641AbfFTR7g (ORCPT ); Thu, 20 Jun 2019 13:59:36 -0400 Received: from mail.kernel.org ([198.145.29.99]:47190 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726551AbfFTR7c (ORCPT ); Thu, 20 Jun 2019 13:59:32 -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 1017D21537; Thu, 20 Jun 2019 17:59:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561053571; bh=hgh0MmmjlfsY1C3iEfMNRRPgfNuNj5U04xYQ2Qpe9fY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=0dams5d6bhSZ/DVpLMCYSWG/4eksdLwoUOlYeq31u0watjz+aXai+z6vP7w5J2NnR zfw6cfvnpePkRYBnNKyJvq4girl1GV/Lfh0NTLoYMI7WHJhP14nFWIgbsNk5PoIOmu LOoMe8PT7XMYwYPieX+toBOFIoCrXYC6fT6ACe6E= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Cyrill Gorcunov , Andrey Vagin , Dmitry Safonov <0x7f454c46@gmail.com>, Pavel Emelyanov , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.4 07/84] kernel/sys.c: prctl: fix false positive in validate_prctl_map() Date: Thu, 20 Jun 2019 19:56:04 +0200 Message-Id: <20190620174338.690742443@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190620174337.538228162@linuxfoundation.org> References: <20190620174337.538228162@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 [ Upstream commit a9e73998f9d705c94a8dca9687633adc0f24a19a ] While validating new map we require the @start_data to be strictly less than @end_data, which is fine for regular applications (this is why this nit didn't trigger for that long). These members are set from executable loaders such as elf handers, still it is pretty valid to have a loadable data section with zero size in file, in such case the start_data is equal to end_data once kernel loader finishes. As a result when we're trying to restore such programs the procedure fails and the kernel returns -EINVAL. From the image dump of a program: | "mm_start_code": "0x400000", | "mm_end_code": "0x8f5fb4", | "mm_start_data": "0xf1bfb0", | "mm_end_data": "0xf1bfb0", Thus we need to change validate_prctl_map from strictly less to less or equal operator use. Link: http://lkml.kernel.org/r/20190408143554.GY1421@uranus.lan Fixes: f606b77f1a9e3 ("prctl: PR_SET_MM -- introduce PR_SET_MM_MAP operation") Signed-off-by: Cyrill Gorcunov Cc: Andrey Vagin Cc: Dmitry Safonov <0x7f454c46@gmail.com> Cc: Pavel Emelyanov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- kernel/sys.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/kernel/sys.c b/kernel/sys.c index e2446ade79ba..1855f1bf113e 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1762,7 +1762,7 @@ static int validate_prctl_map(struct prctl_mm_map *prctl_map) ((unsigned long)prctl_map->__m1 __op \ (unsigned long)prctl_map->__m2) ? 0 : -EINVAL error = __prctl_check_order(start_code, <, end_code); - error |= __prctl_check_order(start_data, <, end_data); + error |= __prctl_check_order(start_data,<=, end_data); error |= __prctl_check_order(start_brk, <=, brk); error |= __prctl_check_order(arg_start, <=, arg_end); error |= __prctl_check_order(env_start, <=, env_end); -- 2.20.1