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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7EBB0C433EF for ; Tue, 26 Apr 2022 16:48:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1353456AbiDZQvg (ORCPT ); Tue, 26 Apr 2022 12:51:36 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45096 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346708AbiDZQuo (ORCPT ); Tue, 26 Apr 2022 12:50:44 -0400 Received: from mail-ed1-x54a.google.com (mail-ed1-x54a.google.com [IPv6:2a00:1450:4864:20::54a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2615348302 for ; Tue, 26 Apr 2022 09:45:45 -0700 (PDT) Received: by mail-ed1-x54a.google.com with SMTP id l24-20020a056402231800b00410f19a3103so10612285eda.5 for ; Tue, 26 Apr 2022 09:45:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20210112; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=KgfdOYR2+eRzwy3N1nFbXjWhZjMyNN/8KPMy2HvUIiA=; b=DiXJaiB8AJMG8+A1MDOZ3VuBShHUCaL1GlKQxcD6mV0R7Av/UajF571MXN7vKcH+xJ B9d0v8KhVCzlQ+z94pkBBtVLTSnlc2yIkyIXP0B+bFCdaqtmHA9pe8/5NYuKcmD5Vy3L fA34cdtJjSamNgh5dsmbUVd7b9zA7hnjKOjdt88/6jqxc/UG3ZHi4m5Nam5rWzqbzqPm cd06DBJ3ACVxlq9XrgpCh+wVKQori1dj0NvbQ7HSZw0NjHsIf9jtgKdLkxo1euBXeZpk ExnDMib7ea+byjuGF4JqXiPnkpgw3Zh2HRRI3cVSjxCjQ97crsBXKlz1IuJlZ96GONPP Cgcw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=KgfdOYR2+eRzwy3N1nFbXjWhZjMyNN/8KPMy2HvUIiA=; b=BGou/RkgZRvdZWK5APnCgjMVwxJrQ0C2f6hhmhd91xVzoXAxo6a4toYA3/5jgUrgK4 15VHCK2Y6Mq+gs/YgaDZPrVqvvXjzWya0ofAqS7GPAeD5uz3MiEOnjS+ACrUweyBvVG3 wRUvxNBAF3CZmKesjiw2z67FJ8tYV1lEKhCRSJv6xR9Zj9y/JVaM377xDko3kVV541Ny 2Khl/8V74AqtRgTQrKGPDw4cDL/cQFL4H/2HrAzq6HXJ99LokU3Jl/exQQgKu06UigJY S61dACCbvfigUUNtJmWV2muhDjKD6F6vS3+7OA9bHTtoeyHaDoCq/N07SOfGhxv+LEnL /w/g== X-Gm-Message-State: AOAM532msI6eWpTZ3R3O7wHB5sQVdWSwMGmzZuDTO5ZTxY0GJbrEYh06 woA4h2mn1JpOivt4AxvZhvWolMXH6EQ= X-Google-Smtp-Source: ABdhPJzCT8fH32RoUVNaiZCyh2VQrj6uF5kLZlCQX+kBGFsZsTKhLxpnKoIswBSqwHZF0t1dzIj5uX6h2dU= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:d580:abeb:bf6d:5726]) (user=glider job=sendgmr) by 2002:a05:6402:26c7:b0:423:e5d6:b6c6 with SMTP id x7-20020a05640226c700b00423e5d6b6c6mr25480700edd.61.1650991543391; Tue, 26 Apr 2022 09:45:43 -0700 (PDT) Date: Tue, 26 Apr 2022 18:43:01 +0200 In-Reply-To: <20220426164315.625149-1-glider@google.com> Message-Id: <20220426164315.625149-33-glider@google.com> Mime-Version: 1.0 References: <20220426164315.625149-1-glider@google.com> X-Mailer: git-send-email 2.36.0.rc2.479.g8af0fa9b8e-goog Subject: [PATCH v3 32/46] kmsan: disable physical page merging in biovec From: Alexander Potapenko To: glider@google.com Cc: Alexander Viro , Andrew Morton , Andrey Konovalov , Andy Lutomirski , Arnd Bergmann , Borislav Petkov , Christoph Hellwig , Christoph Lameter , David Rientjes , Dmitry Vyukov , Eric Dumazet , Greg Kroah-Hartman , Herbert Xu , Ilya Leoshkevich , Ingo Molnar , Jens Axboe , Joonsoo Kim , Kees Cook , Marco Elver , Mark Rutland , Matthew Wilcox , "Michael S. Tsirkin" , Pekka Enberg , Peter Zijlstra , Petr Mladek , Steven Rostedt , Thomas Gleixner , Vasily Gorbik , Vegard Nossum , Vlastimil Babka , kasan-dev@googlegroups.com, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org KMSAN metadata for adjacent physical pages may not be adjacent, therefore accessing such pages together may lead to metadata corruption. We disable merging pages in biovec to prevent such corruptions. Signed-off-by: Alexander Potapenko --- Link: https://linux-review.googlesource.com/id/Iece16041be5ee47904fbc98121b105e5be5fea5c --- block/blk.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/block/blk.h b/block/blk.h index 8ccbc6e076369..95815ac559743 100644 --- a/block/blk.h +++ b/block/blk.h @@ -93,6 +93,13 @@ static inline bool biovec_phys_mergeable(struct request_queue *q, phys_addr_t addr1 = page_to_phys(vec1->bv_page) + vec1->bv_offset; phys_addr_t addr2 = page_to_phys(vec2->bv_page) + vec2->bv_offset; + /* + * Merging adjacent physical pages may not work correctly under KMSAN + * if their metadata pages aren't adjacent. Just disable merging. + */ + if (IS_ENABLED(CONFIG_KMSAN)) + return false; + if (addr1 + vec1->bv_len != addr2) return false; if (xen_domain() && !xen_biovec_phys_mergeable(vec1, vec2->bv_page)) -- 2.36.0.rc2.479.g8af0fa9b8e-goog