From patchwork Thu Jan 3 18:45:20 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10747725 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 5D69914E5 for ; Thu, 3 Jan 2019 18:45:48 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 50D4728D04 for ; Thu, 3 Jan 2019 18:45:48 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 40A6028D06; Thu, 3 Jan 2019 18:45:48 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI, USER_IN_DEF_DKIM_WL autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id EF5F228D04 for ; Thu, 3 Jan 2019 18:45:47 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726254AbfACSpm (ORCPT ); Thu, 3 Jan 2019 13:45:42 -0500 Received: from mail-wr1-f66.google.com ([209.85.221.66]:39532 "EHLO mail-wr1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726242AbfACSpa (ORCPT ); Thu, 3 Jan 2019 13:45:30 -0500 Received: by mail-wr1-f66.google.com with SMTP id t27so34500190wra.6 for ; Thu, 03 Jan 2019 10:45:29 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references :mime-version:content-transfer-encoding; bh=wqfuZcAjUCBtOLKWkS6SRZq/hte3EYpV7rEPQw3hkz8=; b=Ba8p1LN6oK3Pi0Fl7zZMXYDUR1uRcqSUKMdpT1Q7mAQ6syoy5qLvkHGMUj6j/vGuB2 mPO5FuGEoA96YcXVqzSpSwHEKELmv7R+EvR+inn+PIduuMt4TwXWHgaGeZc0ky7vvm86 yH9L4u9oYTTxmMJbx5HQX1aqZm017enJlCtGAbNGdHs15wOBu7Y61tXbAM6zeVySF49T mmuEIvLHrEZb5taS7g9ooF90sN5EBjH7gGfduXn1VTHmhUOpSR2P22jZqk1x1eBZqFiP sH2YY6VeZEfqquy8gfHxRd99KsANe2ythZVkjVH7ZxaZekAiskkZhF+Vg3IKqAONrIV4 HEZg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=wqfuZcAjUCBtOLKWkS6SRZq/hte3EYpV7rEPQw3hkz8=; b=MrvPTtn3L5U4es/AZnSuEzzNngN1N2NQ1g0s3Wz4GFP2ar5MGEto0hYKts5TgpYAzL a8rqkP1hYtOxR0Jo1zGI8mjXlQbjIz6iQCR+u6Dbjlt73f6N22fshUo1apSERG0S/aaD k6dmxj4I6zB6tC54AlvIaV5OmDPaIIt/doTjJYjt/J47mo9Y3LJSFjpJOCOpWGmOuNHU Bb3r8o/ZXV+xyPvx4riKl8lVu4J3jzDupVhcijbBVFQ+gh1Lyj2JrPTK/GcrMRsZGPX7 eaQMWRAeOmjT4BMHDOmGwXPTmuDsWMT6gxz9IIz1+GwOOIw907x9Mws+vpbsRY+KIhRB mPLg== X-Gm-Message-State: AJcUukdTe71LJnbzbovLT202GrdYlAm1/9XtsQ8klDu/AioWEbDDzw70 ZuIC+FY+gCtV3xuHEe97gKHajA== X-Google-Smtp-Source: ALg8bN4LFcO01Vv4WTRKcuv5YTd1wsOefh/eH/jXvbvXe+jy9rGwknH3ImOWsoQ1UvdKBEe2ffL9iQ== X-Received: by 2002:a05:6000:f:: with SMTP id h15mr40972842wrx.248.1546541128878; Thu, 03 Jan 2019 10:45:28 -0800 (PST) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:13:8ce:d7fa:9f4c:492]) by smtp.gmail.com with ESMTPSA id t12sm52236944wrr.65.2019.01.03.10.45.27 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Thu, 03 Jan 2019 10:45:27 -0800 (PST) From: Andrey Konovalov To: Andrey Ryabinin , Alexander Potapenko , Dmitry Vyukov , Catalin Marinas , Will Deacon , Christoph Lameter , Andrew Morton , Mark Rutland , Nick Desaulniers , Marc Zyngier , Dave Martin , Ard Biesheuvel , "Eric W . Biederman" , Ingo Molnar , Paul Lawrence , Geert Uytterhoeven , Arnd Bergmann , "Kirill A . Shutemov" , Greg Kroah-Hartman , Kate Stewart , Mike Rapoport , Vincenzo Frascino , kasan-dev@googlegroups.com, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-sparse@vger.kernel.org, linux-mm@kvack.org, linux-kbuild@vger.kernel.org Cc: Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Jann Horn , Mark Brand , Chintan Pandya , Vishwath Mohan , Andrey Konovalov Subject: [PATCH v3 2/3] kasan: make tag based mode work with CONFIG_HARDENED_USERCOPY Date: Thu, 3 Jan 2019 19:45:20 +0100 Message-Id: <7e756a298d514c4482f52aea6151db34818d395d.1546540962.git.andreyknvl@google.com> X-Mailer: git-send-email 2.20.1.415.g653613c723-goog In-Reply-To: References: MIME-Version: 1.0 Sender: linux-sparse-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-sparse@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP With CONFIG_HARDENED_USERCOPY enabled __check_heap_object() compares and then subtracts a potentially tagged pointer with a non-tagged address of the page that this pointer belongs to, which leads to unexpected behavior. Untag the pointer in __check_heap_object() before doing any of these operations. Signed-off-by: Andrey Konovalov --- mm/slub.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/mm/slub.c b/mm/slub.c index 36c0befeebd8..1e3d0ec4e200 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -3846,6 +3846,8 @@ void __check_heap_object(const void *ptr, unsigned long n, struct page *page, unsigned int offset; size_t object_size; + ptr = kasan_reset_tag(ptr); + /* Find object and usable object size. */ s = page->slab_cache;