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=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 467A1ECDE4B for ; Thu, 8 Nov 2018 22:03:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 09F2620892 for ; Thu, 8 Nov 2018 22:03:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="CpfpbjI+" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 09F2620892 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linuxfoundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731293AbeKIHlS (ORCPT ); Fri, 9 Nov 2018 02:41:18 -0500 Received: from mail.kernel.org ([198.145.29.99]:32942 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730843AbeKIHlM (ORCPT ); Fri, 9 Nov 2018 02:41:12 -0500 Received: from localhost (unknown [208.72.13.198]) (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 371EF208E3; Thu, 8 Nov 2018 22:03:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1541714623; bh=ZQO8ZnxdDvEyIRxWuBmCzesDsKhktkP1Hz6VUDExbAg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CpfpbjI+ZqQ2ntcxkJk8XWyFYJ2/hvI9vmeElfwhz6DhGvO3cZhPJvOkpP5LNbZNd m1i6ueCbqi2ETFbK3EzetlzayDjdVFjKYD/c3tpuaSoOt4pDMChEHSmwSIfllWNZCm Lb18F31eIBrZuqNcBh7MWh9NDu9/OM1TvKgeUsRA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, zhong jiang , Toshi Kani , Vlastimil Babka , Mel Gorman , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH 4.9 033/171] mm/memory_hotplug.c: fix overflow in test_pages_in_a_zone() Date: Thu, 8 Nov 2018 13:50:03 -0800 Message-Id: <20181108215129.734082951@linuxfoundation.org> X-Mailer: git-send-email 2.19.1 In-Reply-To: <20181108215127.257643509@linuxfoundation.org> References: <20181108215127.257643509@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review 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 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ [ Upstream commit d6d8c8a48291b929b2e039f220f0b62958cccfea ] When mainline introduced commit a96dfddbcc04 ("base/memory, hotplug: fix a kernel oops in show_valid_zones()"), it obtained the valid start and end pfn from the given pfn range. The valid start pfn can fix the actual issue, but it introduced another issue. The valid end pfn will may exceed the given end_pfn. Although the incorrect overflow will not result in actual problem at present, but I think it need to be fixed. [toshi.kani@hpe.com: remove assumption that end_pfn is aligned by MAX_ORDER_NR_PAGES] Fixes: a96dfddbcc04 ("base/memory, hotplug: fix a kernel oops in show_valid_zones()") Link: http://lkml.kernel.org/r/1486467299-22648-1-git-send-email-zhongjiang@huawei.com Signed-off-by: zhong jiang Signed-off-by: Toshi Kani Cc: Vlastimil Babka Cc: Mel Gorman Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- mm/memory_hotplug.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/memory_hotplug.c b/mm/memory_hotplug.c index c9f715b2917f..0f962cc3f1bf 100644 --- a/mm/memory_hotplug.c +++ b/mm/memory_hotplug.c @@ -1508,7 +1508,7 @@ int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, while ((i < MAX_ORDER_NR_PAGES) && !pfn_valid_within(pfn + i)) i++; - if (i == MAX_ORDER_NR_PAGES) + if (i == MAX_ORDER_NR_PAGES || pfn + i >= end_pfn) continue; page = pfn_to_page(pfn + i); if (zone && page_zone(page) != zone) @@ -1522,7 +1522,7 @@ int test_pages_in_a_zone(unsigned long start_pfn, unsigned long end_pfn, if (zone) { *valid_start = start; - *valid_end = end; + *valid_end = min(end, end_pfn); return 1; } else { return 0; -- 2.17.1