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 X-Spam-Level: X-Spam-Status: No, score=-12.6 required=3.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED,DKIM_INVALID,DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 53BF1C43461 for ; Wed, 16 Sep 2020 00:39:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0F1D620809 for ; Wed, 16 Sep 2020 00:39:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=google.com header.i=@google.com header.b="d3vnLLe0" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726255AbgIPAjO (ORCPT ); Tue, 15 Sep 2020 20:39:14 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52154 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726616AbgIONXn (ORCPT ); Tue, 15 Sep 2020 09:23:43 -0400 Received: from mail-ed1-x549.google.com (mail-ed1-x549.google.com [IPv6:2a00:1450:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C67F6C061224 for ; Tue, 15 Sep 2020 06:21:18 -0700 (PDT) Received: by mail-ed1-x549.google.com with SMTP id bm14so1262253edb.2 for ; Tue, 15 Sep 2020 06:21:18 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=PB2wGlTtPDen/ye2PAmCBJ5c7LyFB91+1y/zC60t16Q=; b=d3vnLLe0U27rdkUw/utMWI85Xqzo+BSvZHBoRRA5UpSEUiwObUd8MUdZPiQgUmCxJE UU7k9SmgcCbhS4xrIxHj/eIp9ga6OFHSD46K5FKAmZYBXjgdal+8pkIlzG+mp0MI0XOB HujQdhVlUlkQxdr6yevSBsMmhuVb5bbisjqvlAf1r15ix/2aSUTJ2Utmuf7L0CqvDx7Y /laxAwwfx+jMKKTFN6ycu3qqnSv2HlzUfsdq9YQyJ8lfYi2Z8kg4YXMkBRuJuKfzcpjO zz2n+hfmdsfxaSK8J2mJIbjQ6WNkfgf8NRADMQVSV6ljxs+unDr1HFk+WXNbQE28Rmen p5kQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=PB2wGlTtPDen/ye2PAmCBJ5c7LyFB91+1y/zC60t16Q=; b=cuZHYfutgOBhpOGHnUUAEb0O8iNrPZBmAZ2gaXpdXUr8QMjTLmmR08IyJJ2o/HYVC9 p0t7OtPFnGCMFgbDqs/fZbFUDdvwQmFTeNgY5zRGXXDgH6buHpszKDgmwiGVx0bqt3b0 V+0wYowLc/YlPJoqJeiBQkhbzM1JH2kc/zDYFBXYPP7h1PZL6NF2n45/l6L7vK862kjF o1lzhqoLhciNUjCsH+Qdq2+WeE/MWzYhMuNwAyB+cEQQAPAXWkBrE0DD7P3eaba2CZxK PZ4hkti90vaOBBNp9yVXCrhTdwbyljxjs7LwIQJDHrVw2xIWvOM3RcPiglWKZxwwAg+6 frKQ== X-Gm-Message-State: AOAM530+MbBQx2fwgmgzbgy2VBNPxVBzHJ19ny3QYVO+NCKC+yS4TA+x vmjIzkkcpWqWvRQwbTydSLzPLU9IlA== X-Google-Smtp-Source: ABdhPJyR9PqthVFqW2D/mp1NRmsTwOdF86pvoPu4AcBXbRv/V6Z/eH3CtUVQX2fa/YvMlBOBYNXzgwBGqQ== X-Received: from elver.muc.corp.google.com ([2a00:79e0:15:13:f693:9fff:fef4:2449]) (user=elver job=sendgmr) by 2002:a17:907:264c:: with SMTP id ar12mr20711635ejc.80.1600176073238; Tue, 15 Sep 2020 06:21:13 -0700 (PDT) Date: Tue, 15 Sep 2020 15:20:42 +0200 In-Reply-To: <20200915132046.3332537-1-elver@google.com> Message-Id: <20200915132046.3332537-7-elver@google.com> Mime-Version: 1.0 References: <20200915132046.3332537-1-elver@google.com> X-Mailer: git-send-email 2.28.0.618.gf4bc123cb7-goog Subject: [PATCH v2 06/10] kfence, kasan: make KFENCE compatible with KASAN From: Marco Elver To: elver@google.com, akpm@linux-foundation.org, glider@google.com Cc: hpa@zytor.com, paulmck@kernel.org, andreyknvl@google.com, aryabinin@virtuozzo.com, luto@kernel.org, bp@alien8.de, catalin.marinas@arm.com, cl@linux.com, dave.hansen@linux.intel.com, rientjes@google.com, dvyukov@google.com, edumazet@google.com, gregkh@linuxfoundation.org, mingo@redhat.com, jannh@google.com, Jonathan.Cameron@huawei.com, corbet@lwn.net, iamjoonsoo.kim@lge.com, keescook@chromium.org, mark.rutland@arm.com, penberg@kernel.org, peterz@infradead.org, cai@lca.pw, tglx@linutronix.de, vbabka@suse.cz, will@kernel.org, x86@kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, linux-arm-kernel@lists.infradead.org, linux-mm@kvack.org Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Alexander Potapenko We make KFENCE compatible with KASAN for testing KFENCE itself. In particular, KASAN helps to catch any potential corruptions to KFENCE state, or other corruptions that may be a result of freepointer corruptions in the main allocators. To indicate that the combination of the two is generally discouraged, CONFIG_EXPERT=y should be set. It also gives us the nice property that KFENCE will be build-tested by allyesconfig builds. Co-developed-by: Marco Elver Signed-off-by: Marco Elver Signed-off-by: Alexander Potapenko --- lib/Kconfig.kfence | 2 +- mm/kasan/common.c | 7 +++++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/lib/Kconfig.kfence b/lib/Kconfig.kfence index 6a90fef41832..872bcbdd8cc4 100644 --- a/lib/Kconfig.kfence +++ b/lib/Kconfig.kfence @@ -10,7 +10,7 @@ config HAVE_ARCH_KFENCE_STATIC_POOL menuconfig KFENCE bool "KFENCE: low-overhead sampling-based memory safety error detector" - depends on HAVE_ARCH_KFENCE && !KASAN && (SLAB || SLUB) + depends on HAVE_ARCH_KFENCE && (!KASAN || EXPERT) && (SLAB || SLUB) depends on JUMP_LABEL # To ensure performance, require jump labels select STACKTRACE help diff --git a/mm/kasan/common.c b/mm/kasan/common.c index 950fd372a07e..f5c49f0fdeff 100644 --- a/mm/kasan/common.c +++ b/mm/kasan/common.c @@ -18,6 +18,7 @@ #include #include #include +#include #include #include #include @@ -396,6 +397,9 @@ static bool __kasan_slab_free(struct kmem_cache *cache, void *object, tagged_object = object; object = reset_tag(object); + if (is_kfence_address(object)) + return false; + if (unlikely(nearest_obj(cache, virt_to_head_page(object), object) != object)) { kasan_report_invalid_free(tagged_object, ip); @@ -444,6 +448,9 @@ static void *__kasan_kmalloc(struct kmem_cache *cache, const void *object, if (unlikely(object == NULL)) return NULL; + if (is_kfence_address(object)) + return (void *)object; + redzone_start = round_up((unsigned long)(object + size), KASAN_SHADOW_SCALE_SIZE); redzone_end = round_up((unsigned long)object + cache->object_size, -- 2.28.0.618.gf4bc123cb7-goog