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=-10.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 A5CC3FC6194 for ; Fri, 8 Nov 2019 12:36:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7295C222CE for ; Fri, 8 Nov 2019 12:36:15 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573216575; bh=nYbH7ai0svh3IJ+d+tWPxdVI70VLpcJYJy041VKCj5M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=gIOZKGFee0yHg7uS93M0xS/Zyj/6tlqLBD0XlF8q8MLhEQEM4J+9RYMQIDsVHeUhO UxbiTssz+iJ0GZHWovmTrOcPtW/chLkRnbKQJyS1IXigNHD1qBv9ZDLkdnk8oM6Mcb 4+u7vPBvqjv2hws/HQOK3TZLj6TpbqOxQcytVu5c= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726917AbfKHMgP (ORCPT ); Fri, 8 Nov 2019 07:36:15 -0500 Received: from mail.kernel.org ([198.145.29.99]:43758 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726251AbfKHMgO (ORCPT ); Fri, 8 Nov 2019 07:36:14 -0500 Received: from localhost.localdomain (lfbn-mar-1-550-151.w90-118.abo.wanadoo.fr [90.118.131.151]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 76603222D1; Fri, 8 Nov 2019 12:36:12 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1573216573; bh=nYbH7ai0svh3IJ+d+tWPxdVI70VLpcJYJy041VKCj5M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Q2jwbfUNBojKtgp1anSTCzXjtNYa+g9hC9cXYjj2USLTY2XtQxXpJWmx1Hz4WjgWs isrSVqKak7XbqxDXJ6wHHV740/w2zF4MJoo6NseIbEOCn462BuHqG8bzHMdbR6Vzdt 9npIOaMg1HoA9vAGkUG7io6ExAGimW/u4QZe5PLM= From: Ard Biesheuvel To: stable@vger.kernel.org Cc: linus.walleij@linaro.org, rmk+kernel@armlinux.org.uk, Andrey Ryabinin , Ard Biesheuvel Subject: [PATCH for-stable-4.4 01/50] ARM: 8051/1: put_user: fix possible data corruption in put_user Date: Fri, 8 Nov 2019 13:35:05 +0100 Message-Id: <20191108123554.29004-2-ardb@kernel.org> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20191108123554.29004-1-ardb@kernel.org> References: <20191108123554.29004-1-ardb@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: stable-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Andrey Ryabinin Commit 537094b64b229bf3ad146042f83e74cf6abe59df upstream. According to arm procedure call standart r2 register is call-cloberred. So after the result of x expression was put into r2 any following function call in p may overwrite r2. To fix this, the result of p expression must be saved to the temporary variable before the assigment x expression to __r2. Signed-off-by: Andrey Ryabinin Reviewed-by: Nicolas Pitre Cc: stable@vger.kernel.org Signed-off-by: Russell King Signed-off-by: Ard Biesheuvel --- arch/arm/include/asm/uaccess.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index cd8b589111ba..35c9db857ebe 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -251,7 +251,7 @@ extern int __put_user_8(void *, unsigned long long); ({ \ unsigned long __limit = current_thread_info()->addr_limit - 1; \ const typeof(*(p)) __user *__tmp_p = (p); \ - register typeof(*(p)) __r2 asm("r2") = (x); \ + register const typeof(*(p)) __r2 asm("r2") = (x); \ register const typeof(*(p)) __user *__p asm("r0") = __tmp_p; \ register unsigned long __l asm("r1") = __limit; \ register int __e asm("r0"); \ -- 2.20.1