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=-9.8 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 50189C35242 for ; Fri, 24 Jan 2020 09:57:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 20D252075D for ; Fri, 24 Jan 2020 09:57:38 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579859858; bh=UcGNx/ribASwYB5bYwww9OPS0GEK816IiSrkyUveH4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=tS0uoq4TX4TFt8pfmfTmuyJF1FLyml6lerUn1cQ4YlaqhVXDvaYjV8IzL6kMO8hfb KArPH3ev7StyfIsZj3uplfIYVgL4a0cuCUxQkKy+CbGB6L4LwP8mYOiSJd+KWz1nry IGepJ1tx5PYbzpN2nqREyOp3LcOJTnCDcwFBHYXY= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732925AbgAXJ5h (ORCPT ); Fri, 24 Jan 2020 04:57:37 -0500 Received: from mail.kernel.org ([198.145.29.99]:33186 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729990AbgAXJ5h (ORCPT ); Fri, 24 Jan 2020 04:57:37 -0500 Received: from localhost (unknown [145.15.244.15]) (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 06E4720709; Fri, 24 Jan 2020 09:57:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1579859856; bh=UcGNx/ribASwYB5bYwww9OPS0GEK816IiSrkyUveH4I=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=btjF0CPnrPlQ7/NwsAiphbo1YABFsYjAJLI6AVEKVTSS+YjqImOD7eOwXU1n8Cduy nMAejxnXFnBvsS0m7WuR05FkLMDzDIPF8aK8qW7hvS3xWGqGw707tz+lUBWLPFt+d3 sLc5HEcbkG6PVNDYq8gOIqhwCxLJOY3U+wdxMy0Y= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Robert Richter , Borislav Petkov , "linux-edac@vger.kernel.org" , James Morse , Mauro Carvalho Chehab , Sasha Levin Subject: [PATCH 4.14 210/343] EDAC/mc: Fix edac_mc_find() in case no device is found Date: Fri, 24 Jan 2020 10:30:28 +0100 Message-Id: <20200124092947.711378247@linuxfoundation.org> X-Mailer: git-send-email 2.25.0 In-Reply-To: <20200124092919.490687572@linuxfoundation.org> References: <20200124092919.490687572@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: Robert Richter [ Upstream commit 29a0c843973bc385918158c6976e4dbe891df969 ] The function should return NULL in case no device is found, but it always returns the last checked mc device from the list even if the index did not match. Fix that. I did some analysis why this did not raise any issues for about 3 years and the reason is that edac_mc_find() is mostly used to search for existing devices. Thus, the bug is not triggered. [ bp: Drop the if (mci->mc_idx > idx) test in favor of readability. ] Fixes: c73e8833bec5 ("EDAC, mc: Fix locking around mc_devices list") Signed-off-by: Robert Richter Signed-off-by: Borislav Petkov Cc: "linux-edac@vger.kernel.org" Cc: James Morse Cc: Mauro Carvalho Chehab Link: https://lkml.kernel.org/r/20190514104838.15065-1-rrichter@marvell.com Signed-off-by: Sasha Levin --- drivers/edac/edac_mc.c | 12 ++++-------- 1 file changed, 4 insertions(+), 8 deletions(-) diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c index f7fa05fee45a1..329021189c38b 100644 --- a/drivers/edac/edac_mc.c +++ b/drivers/edac/edac_mc.c @@ -680,22 +680,18 @@ static int del_mc_from_global_list(struct mem_ctl_info *mci) struct mem_ctl_info *edac_mc_find(int idx) { - struct mem_ctl_info *mci = NULL; + struct mem_ctl_info *mci; struct list_head *item; mutex_lock(&mem_ctls_mutex); list_for_each(item, &mc_devices) { mci = list_entry(item, struct mem_ctl_info, link); - - if (mci->mc_idx >= idx) { - if (mci->mc_idx == idx) { - goto unlock; - } - break; - } + if (mci->mc_idx == idx) + goto unlock; } + mci = NULL; unlock: mutex_unlock(&mem_ctls_mutex); return mci; -- 2.20.1