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 97656C43334 for ; Mon, 13 Jun 2022 20:54:49 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351085AbiFMUyq (ORCPT ); Mon, 13 Jun 2022 16:54:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37148 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347572AbiFMUxP (ORCPT ); Mon, 13 Jun 2022 16:53:15 -0400 Received: from out0.migadu.com (out0.migadu.com [IPv6:2001:41d0:2:267::]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 36023DE98 for ; Mon, 13 Jun 2022 13:15:25 -0700 (PDT) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1655151324; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=M2+xlJvtrt/Ak+lac7lfuJjlG7HoHnjjsXRwZzO2wkQ=; b=D7+1mF++R9rQSyexDmLe4W43C6kZeCzNSBrDNdQTA+MttNF7gXjdHPZhzzpixGpWrrZc6t QTCBf0IP0biwlIgnvWlisHawkeaiNLKJyhDsmcZfG5NfvfKzCCHagM+dR5BuUGdO4uv0TP LRUfpmJCeWw5nPyMl1dFBPg0mKF7iiw= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Peter Collingbourne , Evgenii Stepanov , Florian Mayer , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH 01/32] kasan: check KASAN_NO_FREE_META in __kasan_metadata_size Date: Mon, 13 Jun 2022 22:13:52 +0200 Message-Id: <91406e5f2a1c0a1fddfc4e7f17df22fda852591c.1655150842.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Andrey Konovalov __kasan_metadata_size() calculates the size of the redzone for objects in a slab cache. When accounting for presence of kasan_free_meta in the redzone, this function only compares free_meta_offset with 0. But free_meta_offset could also be equal to KASAN_NO_FREE_META, which indicates that kasan_free_meta is not present at all. Add a comparison with KASAN_NO_FREE_META into __kasan_metadata_size(). Signed-off-by: Andrey Konovalov --- This is a minor fix that only affects slub_debug runs, so it is probably not worth backporting. --- mm/kasan/common.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/mm/kasan/common.c b/mm/kasan/common.c index c40c0e7b3b5f..968d2365d8c1 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -223,8 +223,9 @@ size_t __kasan_metadata_size(struct kmem_cache *cache) return 0; return (cache->kasan_info.alloc_meta_offset ? sizeof(struct kasan_alloc_meta) : 0) + - (cache->kasan_info.free_meta_offset ? - sizeof(struct kasan_free_meta) : 0); + ((cache->kasan_info.free_meta_offset && + cache->kasan_info.free_meta_offset != KASAN_NO_FREE_META) ? + sizeof(struct kasan_free_meta) : 0); } struct kasan_alloc_meta *kasan_get_alloc_meta(struct kmem_cache *cache, -- 2.25.1