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 9DD0BC2BBC7 for ; Sat, 11 Apr 2020 12:16:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7669520692 for ; Sat, 11 Apr 2020 12:16:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586607411; bh=Eobpd9rfyW8Qda/LHzk612GzKUUTgzhzbdaqq0G/zYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=QqmT4/S3bUsgF9x3XzGJDerwjpB4qsR0EaypVqvUXJtuhvk6tViNWnU2BJh+JaVB7 tCtPFi/DutDyK68ynRbfQxWonPvylbePka2afCE5H/I+7knMxXGiDv6j4AQMfLOq/R Ym1bmILbkjdu4NYj/3okB0lI6iBu1eUDiVR9VIrM= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727870AbgDKMQt (ORCPT ); Sat, 11 Apr 2020 08:16:49 -0400 Received: from mail.kernel.org ([198.145.29.99]:51150 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728290AbgDKMQq (ORCPT ); Sat, 11 Apr 2020 08:16:46 -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 AD68020692; Sat, 11 Apr 2020 12:16:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1586607407; bh=Eobpd9rfyW8Qda/LHzk612GzKUUTgzhzbdaqq0G/zYM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tWwjG30LFsx7k1Ltz53Ti0EoqnbQ+2bzCb9HP/mVDNjCEX2iX6NVzO4DxI8uizTWF BXM9MGeKjqLLACZlvyb6xFnyCLicebo+AuhAq49eO9IyTaas5kyDdOABljYQBrlcLm sLkqHsQ74PMdkMOFvXQK6xQP50vW49wtEgS0vUZk= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Miklos Szeredi , Theodore Tso Subject: [PATCH 4.19 25/54] bitops: protect variables in set_mask_bits() macro Date: Sat, 11 Apr 2020 14:09:07 +0200 Message-Id: <20200411115511.029870714@linuxfoundation.org> X-Mailer: git-send-email 2.26.0 In-Reply-To: <20200411115508.284500414@linuxfoundation.org> References: <20200411115508.284500414@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Miklos Szeredi commit 18127429a854e7607b859484880b8e26cee9ddab upstream. Unprotected naming of local variables within the set_mask_bits() can easily lead to using the wrong scope. Noticed this when "set_mask_bits(&foo->bar, 0, mask)" behaved as no-op. Signed-off-by: Miklos Szeredi Fixes: 00a1a053ebe5 ("ext4: atomically set inode->i_flags in ext4_set_inode_flags()") Cc: Theodore Ts'o Signed-off-by: Greg Kroah-Hartman --- include/linux/bitops.h | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -236,17 +236,17 @@ static __always_inline void __assign_bit #ifdef __KERNEL__ #ifndef set_mask_bits -#define set_mask_bits(ptr, _mask, _bits) \ +#define set_mask_bits(ptr, mask, bits) \ ({ \ - const typeof(*ptr) mask = (_mask), bits = (_bits); \ - typeof(*ptr) old, new; \ + const typeof(*(ptr)) mask__ = (mask), bits__ = (bits); \ + typeof(*(ptr)) old__, new__; \ \ do { \ - old = READ_ONCE(*ptr); \ - new = (old & ~mask) | bits; \ - } while (cmpxchg(ptr, old, new) != old); \ + old__ = READ_ONCE(*(ptr)); \ + new__ = (old__ & ~mask__) | bits__; \ + } while (cmpxchg(ptr, old__, new__) != old__); \ \ - new; \ + new__; \ }) #endif