From patchwork Wed Aug 29 11:35:12 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Andrey Konovalov X-Patchwork-Id: 10580041 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 A63DC17DE for ; Wed, 29 Aug 2018 11:42:31 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 924E42AE0A for ; Wed, 29 Aug 2018 11:42:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 7DAFE2ADA2; Wed, 29 Aug 2018 11:42:31 +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=-2.9 required=2.0 tests=BAYES_00,DKIM_ADSP_CUSTOM_MED, DKIM_SIGNED,DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_NONE autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 263D92ADEF for ; Wed, 29 Aug 2018 11:42:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=T41AxjwIkDEmRugLOl3jmwj2j8TvjGIIwsuWZDCIqUc=; b=oGBNubEqOsSLqZ kNxKmcWWYSzlCBplFuhSGo65MkzODqF+nmzPQ/fwYhXxtP4BgljlqCtZ9rHNVgxZzvDI80D7hkASo +AerXnNoAGR2uLoLYD9SRVz2wgAByv9W6bjhzvh17Ix3yyXWJXMrOpxmzlKgXDs6KJk1mGPvYO1JO cOWYnOMFZS87zpan9cSNUlcqMimBTET9QxyLijlzzFH3XZ3O2oZ61Fb36kTsIkKf9OSLF43g5DjkI Yt0bUtlp/3N1Q99keAsrb+bFJrspf1yO3wQodxpm38XmDgkcdOwencjOD0+Lgu6Az5SLUHy/L7pa5 a6vUMG/qSg440SUloUJA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1fuyrW-0000J4-Ql; Wed, 29 Aug 2018 11:42:14 +0000 Received: from mail-wm0-x242.google.com ([2a00:1450:400c:c09::242]) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1fuylJ-0004X6-Av for linux-arm-kernel@lists.infradead.org; Wed, 29 Aug 2018 11:36:00 +0000 Received: by mail-wm0-x242.google.com with SMTP id m199-v6so4262582wma.1 for ; Wed, 29 Aug 2018 04:35:42 -0700 (PDT) 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=tx0f81qpatBTU8Zf6Dt4IAw08NEBAMzFHV/7KuZJzc4=; b=tGIcisOz2STm0aJshASbTJeJ69RT8JMoAH3f4aCxVwgBItaA52XRJ9qdZYIaZsI2u5 84WxLKUwRjMLHaDEbGCci5rvpBoXQf4II3EtOgQRIvriYehFbI+64zM0dxij1O8dZcgA 0d4nuejpivMGGQO1gx9cPHhEWv7CdpbHsbyN8BudnoODPUQmrsBQrUnuYsKojZIqQrCt Y9gel9LN3l73cl3wtQZRwiyWtT1nUqrnnz+hgzlv/Tl+9TGC4ePGJhT2Lb0s6waiatxg 2jcKeIiW7gFzRHE/xwny+3A+SxEd+mYTqitxyw5Ii/nxehKFNx+YeMhys9uxy7VlTNq1 bVyQ== 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=tx0f81qpatBTU8Zf6Dt4IAw08NEBAMzFHV/7KuZJzc4=; b=jvkNsXMg6C1v08i8aqpIKG0stIjSjKoY2qeBWn2oCVifIig5hSHC7rEImr0SbsvPYD aCiQ/6JwxWlD+t1roZbbAl0iaLYpGz26Y+jVKrGRBR79iYL0J70Ki0uC+lAigS+Hcm4t TroO5u+4HDgMi9nFe/aXZfm7VKYQoQhAvwxmYpZGlu+M1/9HV/9LcFmrRqZMR1Rs2NOu HrOor6YqLYmfe/OcuQZmiTPwJBSWh9FHsjMFDvBkf5GLDus1KfW7Wj4mtYS7T26Dsc8T uhHT7Q4fKmdBbyCnt4noCP15I2U8Kb80b5DtZge9xzv1QwjNGO27Z6bDe0NPmJDWzIfn E+yQ== X-Gm-Message-State: APzg51Dqf4JI++Jxov6CsfwnO4Oko3ot1HS50ald1lENa+Q31MqKZl7t JVRPH8gicRP73YkdNjPXJ6cmgw== X-Google-Smtp-Source: ANB0VdY0nxFKwxx75PWHyKBWLlnvXmuWojLgvitD/kFGr51SPbBFXRZ2fLWPnFpHFc/eIOY2zo7EzA== X-Received: by 2002:a1c:2dc8:: with SMTP id t191-v6mr4162464wmt.94.1535542540551; Wed, 29 Aug 2018 04:35:40 -0700 (PDT) Received: from andreyknvl0.muc.corp.google.com ([2a00:79e0:15:10:84be:a42a:826d:c530]) by smtp.gmail.com with ESMTPSA id s10-v6sm7800454wmd.22.2018.08.29.04.35.38 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Wed, 29 Aug 2018 04:35:39 -0700 (PDT) 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 , 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 Subject: [PATCH v6 08/18] khwasan: preassign tags to objects with ctors or SLAB_TYPESAFE_BY_RCU Date: Wed, 29 Aug 2018 13:35:12 +0200 Message-Id: <95b5beb7ec13b7e998efe84c9a7a5c1fa49a9fe3.1535462971.git.andreyknvl@google.com> X-Mailer: git-send-email 2.19.0.rc0.228.g281dcd1b4d0-goog In-Reply-To: References: MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20180829_043549_426751_0C09A163 X-CRM114-Status: GOOD ( 16.27 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vishwath Mohan , Chintan Pandya , Jacob Bramley , Jann Horn , Ruben Ayrapetyan , Andrey Konovalov , Lee Smith , Kostya Serebryany , Mark Brand , Ramana Radhakrishnan , Evgeniy Stepanov Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP An object constructor can initialize pointers within this objects based on the address of the object. Since the object address might be tagged, we need to assign a tag before calling constructor. The implemented approach is to assign tags to objects with constructors when a slab is allocated and call constructors once as usual. The downside is that such object would always have the same tag when it is reallocated, so we won't catch use-after-frees on it. Also pressign tags for objects from SLAB_TYPESAFE_BY_RCU caches, since they can be validy accessed after having been freed. Signed-off-by: Andrey Konovalov --- mm/slab.c | 6 +++++- mm/slub.c | 4 ++++ 2 files changed, 9 insertions(+), 1 deletion(-) diff --git a/mm/slab.c b/mm/slab.c index 6fdca9ec2ea4..3b4227059f2e 100644 --- a/mm/slab.c +++ b/mm/slab.c @@ -403,7 +403,11 @@ static inline struct kmem_cache *virt_to_cache(const void *obj) static inline void *index_to_obj(struct kmem_cache *cache, struct page *page, unsigned int idx) { - return page->s_mem + cache->size * idx; + void *obj; + + obj = page->s_mem + cache->size * idx; + obj = khwasan_preset_slab_tag(cache, idx, obj); + return obj; } /* diff --git a/mm/slub.c b/mm/slub.c index 4206e1b616e7..086d6558a6b6 100644 --- a/mm/slub.c +++ b/mm/slub.c @@ -1531,12 +1531,14 @@ static bool shuffle_freelist(struct kmem_cache *s, struct page *page) /* First entry is used as the base of the freelist */ cur = next_freelist_entry(s, page, &pos, start, page_limit, freelist_count); + cur = khwasan_preset_slub_tag(s, cur); page->freelist = cur; for (idx = 1; idx < page->objects; idx++) { setup_object(s, page, cur); next = next_freelist_entry(s, page, &pos, start, page_limit, freelist_count); + next = khwasan_preset_slub_tag(s, next); set_freepointer(s, cur, next); cur = next; } @@ -1613,8 +1615,10 @@ static struct page *allocate_slab(struct kmem_cache *s, gfp_t flags, int node) shuffle = shuffle_freelist(s, page); if (!shuffle) { + start = khwasan_preset_slub_tag(s, start); for_each_object_idx(p, idx, s, start, page->objects) { setup_object(s, page, p); + p = khwasan_preset_slub_tag(s, p); if (likely(idx < page->objects)) set_freepointer(s, p, p + s->size); else