From patchwork Tue Aug 11 05:39:14 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 11708579 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 1E986722 for ; Tue, 11 Aug 2020 05:39:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F2219208B3 for ; Tue, 11 Aug 2020 05:39:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="FV8uMO3a" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728274AbgHKFjq (ORCPT ); Tue, 11 Aug 2020 01:39:46 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54134 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728255AbgHKFjp (ORCPT ); Tue, 11 Aug 2020 01:39:45 -0400 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3A0CEC06174A for ; Mon, 10 Aug 2020 22:39:45 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id j8so8899622qvu.3 for ; Mon, 10 Aug 2020 22:39:45 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=45vX/OukMjmRJbYoiR0tKiPizR257EeVnpqPnjVNEcE=; b=FV8uMO3aqhjqWbi2Tgu6Hf+4cQsDPp+CXiCl3C9oF+52ljsX5mX09Vas3qnKIU8GXK Za5pTaNn7UuRaTl83zJJLC3gdnWAcvDb7og/+aXXsugtYaswwIMKVMMU4v75yer9K7Hc U3UhMilmfY0yw4B9sm+1SL8QTpVXT+IuuWJFX2XEjGAmRz35A6wGp2CjZrnCxwN1BA/0 acTIiPOu9EPlnGxJuFa7hvuKdHATL1QCcXC/t41vf5GsUw6ZPMP0bwHXftyoynnUO0Eq F1EnwJSRefMzr4xasqLztPF6XK21ka4oP3/bbSYVJpcEEAjpaCWnxEGYDaAP+JF3GIiT QL0Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=45vX/OukMjmRJbYoiR0tKiPizR257EeVnpqPnjVNEcE=; b=J7mIRHSJXhhEqxo3NzUu104UWEaGpPlhtuJbzbIZA8eD1MIbRKJU6zbJ4lbtgkkYAL G/1caOEZKLSGRpVbw6W6SB2boTmTiHVG8/imBStIQdns5UOVnKJWyyZh1lCnRH3onDwb 9y1nXTuWmnjCdRQYYRd70RBrwfXLqjWDHLksrPMs/jmN9WsT5KV3utLoWyt1qv1hVADv rfo2j3XwUJ9Gld9xQR4sWPlvUX2MtBZ5V+/u4x8zMA3WAjg9d8zlY6jWROYYEDEmSuj7 tPXtfJtBVRoM50AXwdaxa7uob/wqupDWJU4EAuKVq8jSbbc/t2MVg8HApV23nLpKBCWK 8d+w== X-Gm-Message-State: AOAM531yA2FSfyoIviR40xfH/syPZUmUNIi2V3WHxk6yCS+yxCg5QDtm I2JTRgMcPOq1884Vp+XS9smUZ+JZpIdXFg== X-Google-Smtp-Source: ABdhPJyX6cDzJ29PKias/qfWiHzlxz/CIIlnG39utN5Ohs9jzVf+HpAsJZW9sC7eGOZYJzaiFiHffLfuxlk31A== X-Received: by 2002:a0c:fdeb:: with SMTP id m11mr32366961qvu.103.1597124384218; Mon, 10 Aug 2020 22:39:44 -0700 (PDT) Date: Mon, 10 Aug 2020 22:39:14 -0700 In-Reply-To: <20200811053914.652710-1-davidgow@google.com> Message-Id: <20200811053914.652710-6-davidgow@google.com> Mime-Version: 1.0 References: <20200811053914.652710-1-davidgow@google.com> X-Mailer: git-send-email 2.28.0.236.gb10cc79966-goog Subject: [PATCH v12 5/6] KASAN: Testing Documentation From: David Gow To: trishalfonso@google.com, brendanhiggins@google.com, aryabinin@virtuozzo.com, dvyukov@google.com, mingo@redhat.com, peterz@infradead.org, juri.lelli@redhat.com, vincent.guittot@linaro.org, andreyknvl@google.com, shuah@kernel.org, akpm@linux-foundation.org Cc: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org, linux-mm@kvack.org, David Gow Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org From: Patricia Alfonso Include documentation on how to test KASAN using CONFIG_TEST_KASAN_KUNIT and CONFIG_TEST_KASAN_MODULE. Signed-off-by: Patricia Alfonso Signed-off-by: David Gow Reviewed-by: Andrey Konovalov Reviewed-by: Dmitry Vyukov Acked-by: Brendan Higgins Tested-by: Andrey Konovalov --- Documentation/dev-tools/kasan.rst | 70 +++++++++++++++++++++++++++++++ 1 file changed, 70 insertions(+) diff --git a/Documentation/dev-tools/kasan.rst b/Documentation/dev-tools/kasan.rst index 38fd5681fade..42991e40cbe1 100644 --- a/Documentation/dev-tools/kasan.rst +++ b/Documentation/dev-tools/kasan.rst @@ -281,3 +281,73 @@ unmapped. This will require changes in arch-specific code. This allows ``VMAP_STACK`` support on x86, and can simplify support of architectures that do not have a fixed module region. + +CONFIG_KASAN_KUNIT_TEST & CONFIG_TEST_KASAN_MODULE +-------------------------------------------------- + +``CONFIG_KASAN_KUNIT_TEST`` utilizes the KUnit Test Framework for testing. +This means each test focuses on a small unit of functionality and +there are a few ways these tests can be run. + +Each test will print the KASAN report if an error is detected and then +print the number of the test and the status of the test: + +pass:: + + ok 28 - kmalloc_double_kzfree +or, if kmalloc failed:: + + # kmalloc_large_oob_right: ASSERTION FAILED at lib/test_kasan.c:163 + Expected ptr is not null, but is + not ok 4 - kmalloc_large_oob_right +or, if a KASAN report was expected, but not found:: + + # kmalloc_double_kzfree: EXPECTATION FAILED at lib/test_kasan.c:629 + Expected kasan_data->report_expected == kasan_data->report_found, but + kasan_data->report_expected == 1 + kasan_data->report_found == 0 + not ok 28 - kmalloc_double_kzfree + +All test statuses are tracked as they run and an overall status will +be printed at the end:: + + ok 1 - kasan_kunit_test + +or:: + + not ok 1 - kasan_kunit_test + +(1) Loadable Module +~~~~~~~~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` enabled, ``CONFIG_KASAN_KUNIT_TEST`` can be built as +a loadable module and run on any architecture that supports KASAN +using something like insmod or modprobe. + +(2) Built-In +~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` built-in, ``CONFIG_KASAN_KUNIT_TEST`` can be built-in +on any architecure that supports KASAN. These and any other KUnit +tests enabled will run and print the results at boot as a late-init +call. + +(3) Using kunit_tool +~~~~~~~~~~~~~~~~~~~~~ + +With ``CONFIG_KUNIT`` and ``CONFIG_KASAN_KUNIT_TEST`` built-in, we can also +use kunit_tool to see the results of these along with other KUnit +tests in a more readable way. This will not print the KASAN reports +of tests that passed. Use `KUnit documentation `_ for more up-to-date +information on kunit_tool. + +.. _KUnit: https://www.kernel.org/doc/html/latest/dev-tools/kunit/index.html + +``CONFIG_TEST_KASAN_MODULE`` is a set of KASAN tests that could not be +converted to KUnit. These tests can be run only as a module with +``CONFIG_TEST_KASAN_MODULE`` built as a loadable module and +``CONFIG_KASAN`` built-in. The type of error expected and the +function being run is printed before the expression expected to give +an error. Then the error is printed, if found, and that test +should be interpretted to pass only if the error was the one expected +by the test.