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 61B55C05027 for ; Tue, 14 Feb 2023 12:06:47 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C1C1E6B0073; Tue, 14 Feb 2023 07:06:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BCC3A6B0074; Tue, 14 Feb 2023 07:06:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id A943C6B0075; Tue, 14 Feb 2023 07:06:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 99A836B0073 for ; Tue, 14 Feb 2023 07:06:46 -0500 (EST) Received: from smtpin22.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 68C521C62E5 for ; Tue, 14 Feb 2023 12:06:46 +0000 (UTC) X-FDA: 80465770812.22.20CA063 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by imf17.hostedemail.com (Postfix) with ESMTP id C1EEA40002 for ; Tue, 14 Feb 2023 12:06:42 +0000 (UTC) Authentication-Results: imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="eBK4+Uo/"; spf=pass (imf17.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1676376404; 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:dkim-signature; bh=euiiuweCAO9A3Q4t5/zzDeSJbnrREM9paD+/WzRY4kk=; b=hvAcm1rqjvMPXuKLvAjwYPgXoOSoBf5o9mD8pghUv7ycQsStilPwRQ3LhXzh74vnO/bllo 0un0A3r5/mxVe+QCdiGsyXOVrtIQv5mmd2xvVxMpJ5sQWKGIzf6oH/0bYD2zh/i3/loVWd aAWDiYh3WNzNNQXW/qZkSPBA6dKkPqk= ARC-Authentication-Results: i=1; imf17.hostedemail.com; dkim=pass header.d=redhat.com header.s=mimecast20190719 header.b="eBK4+Uo/"; spf=pass (imf17.hostedemail.com: domain of david@redhat.com designates 170.10.133.124 as permitted sender) smtp.mailfrom=david@redhat.com; dmarc=pass (policy=none) header.from=redhat.com ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1676376404; a=rsa-sha256; cv=none; b=YPJt87M4tvBaZauFwYHeThPXzXFaXa/i5SeO02OeivDVoscSOZohY9bBrWM+EGzJSgYWjJ fZ0AShc5JTaMzNPSAMRMhQhtdb+h1XzOWfOuF0zhVALRPdV71kFxZiE3AX4/IHni/a1L8D 4awKATE56pF5oqPEEi2defjDQVGsSt8= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1676376402; h=from:from: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=euiiuweCAO9A3Q4t5/zzDeSJbnrREM9paD+/WzRY4kk=; b=eBK4+Uo/nUNPk3LAWYKE/djT1BAlz4z3BmnSUic3yhK8fpcrR8F/wxO/fC5icDFhtLheVG hZ/Qyas97FhQhD2PMixG+3NBIMsaL6ai/poqFYDbzC+b5ONyjCP9N1bs5t6RUdd0HepP50 u/6y/qlwcOFIhMQV6YC5JmVIaBWOpBw= Received: from mail-wm1-f70.google.com (mail-wm1-f70.google.com [209.85.128.70]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-224-SQ-aSQ-EPSOg_E-UcdpDUA-1; Tue, 14 Feb 2023 07:06:40 -0500 X-MC-Unique: SQ-aSQ-EPSOg_E-UcdpDUA-1 Received: by mail-wm1-f70.google.com with SMTP id k17-20020a05600c1c9100b003dd41ad974bso8529691wms.3 for ; Tue, 14 Feb 2023 04:06:40 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:organization:from:references :cc:to:content-language:subject:user-agent:mime-version:date :message-id:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=euiiuweCAO9A3Q4t5/zzDeSJbnrREM9paD+/WzRY4kk=; b=zt7exoCeesygkMUVeHo6IfKfVpBo0wqvboE2UPr+0WTivR7fMD4BfRdAvgGg64o419 f9aywk4I1CgOW1YQXjtXsmBO2jy0zp1YXoRxELTVOUpLPnsRMILTQiU31DMIdCur8EOA Yr/UrJMe87e84kAKZE621Wsu2NTET05DFPRimnRmpw9cqoD41GTrGMsKA6YgB5AsdJsG Buvk2GXX6wKmjtOo9O69vBYKli4Zr3bblehcFOHp/QcktJu8fvI+QJjLaivy8J4WAMWO gEZlnY8WU1rWU1yNtFqrzIDpnMfOSccHI0bjd0E4dtSXFpygLtqz9wXjZN7VslB8IVLB r2Yw== X-Gm-Message-State: AO0yUKVYL5ahMjEfV2v+NhJENHGYLmkkw+vfrSMgtYWG7Hwd9eiaKE43 w7Oy1e+653VQ7MUM3MK1I/gUW6i1zDhtKtuHaFqzX7Cr4+DHAK/jpfuSTv1JXmLG8ht7MOSC7cb ORrCfo3ZLwlM= X-Received: by 2002:adf:dcc3:0:b0:2bf:d285:b787 with SMTP id x3-20020adfdcc3000000b002bfd285b787mr1686050wrm.56.1676376399330; Tue, 14 Feb 2023 04:06:39 -0800 (PST) X-Google-Smtp-Source: AK7set+W753jeHqtpGQxLIgDZfvGbzW6/dD0PZ/oQPucec32eb/nFmu/1/JHUAJ2DYZ7/OAI85kjyg== X-Received: by 2002:adf:dcc3:0:b0:2bf:d285:b787 with SMTP id x3-20020adfdcc3000000b002bfd285b787mr1686035wrm.56.1676376399066; Tue, 14 Feb 2023 04:06:39 -0800 (PST) Received: from ?IPV6:2003:cb:c709:1700:969:8e2b:e8bb:46be? (p200300cbc709170009698e2be8bb46be.dip0.t-ipconnect.de. [2003:cb:c709:1700:969:8e2b:e8bb:46be]) by smtp.gmail.com with ESMTPSA id a7-20020a056000050700b002c3e3ee7d1asm12888230wrf.79.2023.02.14.04.06.38 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 14 Feb 2023 04:06:38 -0800 (PST) Message-ID: Date: Tue, 14 Feb 2023 13:06:37 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.6.0 Subject: Re: [PATCH] mm/khugepaged: Fix invalid page access in release_pte_pages() To: "Vishal Moola (Oracle)" , akpm@linux-foundation.org Cc: willy@infradead.org, m.szyprowski@samsung.com, alex@ghiti.fr, linux-mm@kvack.org References: <20230213214324.34215-1-vishal.moola@gmail.com> From: David Hildenbrand Organization: Red Hat In-Reply-To: <20230213214324.34215-1-vishal.moola@gmail.com> X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Language: en-US Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Rspamd-Queue-Id: C1EEA40002 X-Stat-Signature: dqop5ca446dwmkrjtmjyxsnok8oqwq7i X-Rspam-User: X-Rspamd-Server: rspam08 X-HE-Tag: 1676376402-235494 X-HE-Meta: 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 f5Zq9Opb 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 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: On 13.02.23 22:43, Vishal Moola (Oracle) wrote: > release_pte_pages() converts from a pfn to a folio by using pfn_folio(). > If the pte is not mapped, pfn_folio() will result in undefined behavior > which ends up causing a kernel panic[1]. > > Only call pfn_folio() once we have validated that the pte is both valid > and mapped to fix the issue. > > [1] https://lore.kernel.org/linux-mm/ff300770-afe9-908d-23ed-d23e0796e899@samsung.com/ > > Fixes: 9bdfeea46f49 ("mm/khugepaged: convert release_pte_pages() to use folios") > Reported-by: Marek Szyprowski > Debugged-by: Alexandre Ghiti > Cc: Matthew Wilcox > Signed-off-by: Vishal Moola (Oracle) > --- > mm/khugepaged.c | 14 ++++++++++---- > 1 file changed, 10 insertions(+), 4 deletions(-) > > diff --git a/mm/khugepaged.c b/mm/khugepaged.c > index b39ab219d5b7..bd54b957f69a 100644 > --- a/mm/khugepaged.c > +++ b/mm/khugepaged.c > @@ -511,11 +511,17 @@ static void release_pte_pages(pte_t *pte, pte_t *_pte, > > while (--_pte >= pte) { > pte_t pteval = *_pte; > + unsigned long pfn; > > - folio = pfn_folio(pte_pfn(pteval)); > - if (!pte_none(pteval) && !is_zero_pfn(pte_pfn(pteval)) && > - !folio_test_large(folio)) > - release_pte_folio(folio); > + if (pte_none(pteval)) > + continue; > + pfn = pte_pfn(pteval); > + if (is_zero_pfn(pfn)) > + continue; > + folio = pfn_folio(pfn); > + if (folio_test_large(folio)) > + continue; > + release_pte_folio(folio); > } > > list_for_each_entry_safe(folio, tmp, compound_pagelist, lru) { Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb