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=-9.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,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 9AD27C46475 for ; Thu, 25 Oct 2018 14:14:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6063020856 for ; Thu, 25 Oct 2018 14:14:33 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="iUC8wvbO" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 6063020856 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.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 S1728419AbeJYWr1 (ORCPT ); Thu, 25 Oct 2018 18:47:27 -0400 Received: from mail.kernel.org ([198.145.29.99]:55422 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727433AbeJYWr0 (ORCPT ); Thu, 25 Oct 2018 18:47:26 -0400 Received: from sasha-vm.mshome.net (unknown [167.98.65.38]) (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 79E862084A; Thu, 25 Oct 2018 14:14:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1540476870; bh=R4oY6kskvOrkXr6arZ58DNOMgCJTOGKov0Yw2TPlcj0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=iUC8wvbOvA77R5QPfKhwqGAUl3IP1QsgydBJAZYDZJ+qkivzSqqWO19w6Yg/ugItg Jt+xYV3rX68e6iR09dloA6Tyfz99wOANCRkeozp1DcqaDfr4VeafkMXHCHyO6/N6/B GUDri7E6bpb17091Pji9WwnZ0T5jZ0KBmna61Z1M= From: Sasha Levin To: stable@vger.kernel.org, linux-kernel@vger.kernel.org Cc: zhong jiang , Toshi Kani , Vlastimil Babka , Mel Gorman , Andrew Morton , Linus Torvalds , Sasha Levin Subject: [PATCH AUTOSEL 4.9 02/98] mm/memory_hotplug.c: fix overflow in test_pages_in_a_zone() Date: Thu, 25 Oct 2018 10:12:47 -0400 Message-Id: <20181025141423.213774-2-sashal@kernel.org> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20181025141423.213774-1-sashal@kernel.org> References: <20181025141423.213774-1-sashal@kernel.org> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: zhong jiang [ 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