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=-20.9 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, USER_AGENT_GIT,USER_IN_DEF_DKIM_WL 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 81929C4727C for ; Tue, 29 Sep 2020 13:39:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 26E772145D for ; Tue, 29 Sep 2020 13:39:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="er322a8g" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730415AbgI2Njk (ORCPT ); Tue, 29 Sep 2020 09:39:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57284 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730057AbgI2Ni7 (ORCPT ); Tue, 29 Sep 2020 09:38:59 -0400 Received: from mail-qv1-xf49.google.com (mail-qv1-xf49.google.com [IPv6:2607:f8b0:4864:20::f49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3AD4AC0613D0 for ; Tue, 29 Sep 2020 06:38:58 -0700 (PDT) Received: by mail-qv1-xf49.google.com with SMTP id dj20so2493003qvb.23 for ; Tue, 29 Sep 2020 06:38:58 -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=3PLfj7Le+IfBX8a0VvW3RStHbDZmDhyxflksdHuR0eA=; b=er322a8geG68qcfF8M1guZNd7UF3m56ZBe9jI1gKY2Ai9rDqkC+XsPfeQe+Gxco71+ st8n9YtVCR4QANduoS54PpgWIz6J6ookqFiPylQPXIYD80aa0kVkBrI0GQMqzxcB+L3d aK7WiVxjzJ7vvUxnxIXhu0PvEQrzs4dw2UMzTlKskDDz8x0rnH18gN/SfzheEov2h57l oFMlpwpiR91ep+fcSlbc+dDINYyQ4dbf4MDNW6tu4aGiRvHBQ4H9axwpHrbwzJ6MXPWd 5BkMRw14eXNd/hu+SzMv1DIKxLS/ayUiiOLZSf5jQ1MonoUT6ctvp7gvSgeTZSRC51OM Yeaw== 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=3PLfj7Le+IfBX8a0VvW3RStHbDZmDhyxflksdHuR0eA=; b=Tr842bjQoxgmOChEKeVchshIiBPOqpchfX1zvVNnQaU8P/oitFJ9QGOoZYdR1H7ExG 5g4sWUfdNuZcAipwW/VBC0m6BCFLut8qtwYyukX2Yh5UWBMx9z75KDpCbCiQYA/fLkqt 4xYsD33EMdxKtNPFCEHKeHzQ4/OKMjXA5QGXOAhYIf5SBWQ2rl/8H+9PtmaikUh/V+Rl ECRDVWeKWxzEgtCfC2slpgPlpUUl18PD6thNTknbBX59bXeAtcwav9/zoNuwUTg4LHDi uFvauOhQm96ULhy8Npett2fpavGRJ059MHsPlkHnRRtqSw0ZIRvjEwcH27pv6X55fwnd aEmQ== X-Gm-Message-State: AOAM533EKrKLXFuxZp8E2N1QOQumQ/0GwyETGOQUfhfPLSfyAN3bLQpy eZecn0I5Errd37NXEWtXAAROgC+zLg== X-Google-Smtp-Source: ABdhPJxJbcDYckRS0wVuzRySp2nuYSOJOG2pvGym1ZUIs47gMLvaU61ksR2fPMifrMOlNYqiUa3bx3KdoA== Sender: "elver via sendgmr" X-Received: from elver.muc.corp.google.com ([2a00:79e0:15:13:f693:9fff:fef4:2449]) (user=elver job=sendgmr) by 2002:a05:6214:b0d:: with SMTP id u13mr4600352qvj.17.1601386737145; Tue, 29 Sep 2020 06:38:57 -0700 (PDT) Date: Tue, 29 Sep 2020 15:38:09 +0200 In-Reply-To: <20200929133814.2834621-1-elver@google.com> Message-Id: <20200929133814.2834621-7-elver@google.com> Mime-Version: 1.0 References: <20200929133814.2834621-1-elver@google.com> X-Mailer: git-send-email 2.28.0.709.gb0816b6eb0-goog Subject: [PATCH v4 06/11] 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, hdanton@sina.com, 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, sjpark@amazon.com, 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" 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. Reviewed-by: Dmitry Vyukov 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 4c2ea1c722de..6825c1c07a10 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, -- 2.28.0.709.gb0816b6eb0-goog