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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 58C6BC433EF for ; Mon, 20 Jun 2022 10:54:53 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id DC7F66B0071; Mon, 20 Jun 2022 06:54:52 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id D75DF6B0073; Mon, 20 Jun 2022 06:54:52 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C8B3D8E0001; Mon, 20 Jun 2022 06:54:52 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id B7E176B0071 for ; Mon, 20 Jun 2022 06:54:52 -0400 (EDT) Received: from smtpin15.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 84D4060E3F for ; Mon, 20 Jun 2022 10:54:52 +0000 (UTC) X-FDA: 79598306424.15.6CB472E Received: from out30-54.freemail.mail.aliyun.com (out30-54.freemail.mail.aliyun.com [115.124.30.54]) by imf15.hostedemail.com (Postfix) with ESMTP id 3242DA0093 for ; Mon, 20 Jun 2022 10:54:50 +0000 (UTC) X-Alimail-AntiSpam:AC=PASS;BC=-1|-1;BR=01201311R161e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=ay29a033018045168;MF=xianting.tian@linux.alibaba.com;NM=1;PH=DS;RN=11;SR=0;TI=SMTPD_---0VGvoA2z_1655722484; Received: from B-LB6YLVDL-0141.local(mailfrom:xianting.tian@linux.alibaba.com fp:SMTPD_---0VGvoA2z_1655722484) by smtp.aliyun-inc.com; Mon, 20 Jun 2022 18:54:46 +0800 Subject: Re: [PATCH 5.15] mm: validate buddy page before using To: Greg KH Cc: akpm@linux-foundation.org, ziy@nvidia.com, stable@vger.kernel.org, guoren@kernel.org, huanyi.xj@alibaba-inc.com, guohanjun@huawei.com, zjb194813@alibaba-inc.com, tianhu.hh@alibaba-inc.com, linux-mm@kvack.org, linux-kernel@vger.kernel.org References: <20220616161746.3565225-1-xianting.tian@linux.alibaba.com> <20220616161746.3565225-6-xianting.tian@linux.alibaba.com> From: Xianting Tian Message-ID: <35bd7396-f5aa-e154-9495-0a36fc6f6a33@linux.alibaba.com> Date: Mon, 20 Jun 2022 18:54:44 +0800 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.10.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1655722492; a=rsa-sha256; cv=none; b=bFfdpyYR8pjmVfIu1ciAYA71uIPBe7B0Abbv2A9tx5azk6uRwiivgD8zjPSGMtv4yrrwZv dlOrhIZLnE870IlS5vFdBjwZPNx9dt3G60bxcLLV1/ncqTNuZMywL9d2nI2oxwa1v44uqQ Wt2fLRLzfQLmb1JobFQxOj2nJei6RuM= ARC-Authentication-Results: i=1; imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of xianting.tian@linux.alibaba.com designates 115.124.30.54 as permitted sender) smtp.mailfrom=xianting.tian@linux.alibaba.com; dmarc=pass (policy=none) header.from=alibaba.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1655722492; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=LYi5owyvvk5d44EKWUklhzIUcIvDGzjdulkSjO16j3Q=; b=Ag4B3Uf0OCGG5nbgehNlt7FarOHn4ap5ADuuQtf+XpZbrXiD28iipGSDnntaKg+yc5rSMA lv3SB2BERe8LoOMAPg5ibkME1M4vMEv4j+xf2rN39K/3MJTUCAiYXoNIdMqM8yLiKsJPzn yDxGIW/OJ01r4+THcd/DC4gl0AsTN+A= Authentication-Results: imf15.hostedemail.com; dkim=none; spf=pass (imf15.hostedemail.com: domain of xianting.tian@linux.alibaba.com designates 115.124.30.54 as permitted sender) smtp.mailfrom=xianting.tian@linux.alibaba.com; dmarc=pass (policy=none) header.from=alibaba.com X-Rspam-User: X-Stat-Signature: za45bgz47fsrtqiumkw3upt1oaan75fy X-Rspamd-Queue-Id: 3242DA0093 X-Rspamd-Server: rspam08 X-HE-Tag: 1655722490-674751 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: 在 2022/6/20 下午6:17, Greg KH 写道: > On Fri, Jun 17, 2022 at 12:17:45AM +0800, Xianting Tian wrote: >> Commit 787af64d05cd ("mm: page_alloc: validate buddy before check its migratetype.") >> fixes a bug in 1dd214b8f21c and there is a similar bug in d9dddbf55667 that >> can be fixed in a similar way too. >> >> In unset_migratetype_isolate(), we also need the fix, so move page_is_buddy() >> from mm/page_alloc.c to mm/internal.h >> >> In addition, for RISC-V arch the first 2MB RAM could be reserved for opensbi, >> so it would have pfn_base=512 and mem_map began with 512th PFN when >> CONFIG_FLATMEM=y. >> But __find_buddy_pfn algorithm thinks the start pfn 0, it could get 0 pfn or >> less than the pfn_base value. We need page_is_buddy() to verify the buddy to >> prevent accessing an invalid buddy. >> >> Fixes: d9dddbf55667 ("mm/page_alloc: prevent merging between isolated and other pageblocks") >> Cc: stable@vger.kernel.org >> Reported-by: zjb194813@alibaba-inc.com >> Reported-by: tianhu.hh@alibaba-inc.com >> Signed-off-by: Xianting Tian >> --- >> mm/internal.h | 34 ++++++++++++++++++++++++++++++++++ >> mm/page_alloc.c | 37 +++---------------------------------- >> mm/page_isolation.c | 3 ++- >> 3 files changed, 39 insertions(+), 35 deletions(-) > What is the commit id of this in Linus's tree? It is also this one， commit 787af64d05cd528aac9ad16752d11bb1c6061bb9 Author: Zi Yan Date:   Wed Mar 30 15:45:43 2022 -0700     mm: page_alloc: validate buddy before check its migratetype.     Whenever a buddy page is found, page_is_buddy() should be called to     check its validity.  Add the missing check during pageblock merge check.     Fixes: 1dd214b8f21c ("mm: page_alloc: avoid merging non-fallbackable pageblocks with others")     Link: https://lore.kernel.org/all/20220330154208.71aca532@gandalf.local.home/     Reported-and-tested-by: Steven Rostedt     Signed-off-by: Zi Yan     Signed-off-by: Linus Torvalds > > thanks, > > greg k-h