From patchwork Wed Aug 5 04:29:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 11701285 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 A4C271392 for ; Wed, 5 Aug 2020 04:30:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 940F222CA0 for ; Wed, 5 Aug 2020 04:30:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="TBGXVFSW" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726524AbgHEEaJ (ORCPT ); Wed, 5 Aug 2020 00:30:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45200 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726459AbgHEE36 (ORCPT ); Wed, 5 Aug 2020 00:29:58 -0400 Received: from mail-qt1-x84a.google.com (mail-qt1-x84a.google.com [IPv6:2607:f8b0:4864:20::84a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BE09CC06174A for ; Tue, 4 Aug 2020 21:29:57 -0700 (PDT) Received: by mail-qt1-x84a.google.com with SMTP id r24so10519209qtu.3 for ; Tue, 04 Aug 2020 21:29:57 -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=nr8mXyqoppq75z/FRAmv2PARhpMnaUiNjcYddLk+74Y=; b=TBGXVFSWKjIeEBqhvRaejVcq72l1gKFOpsaGCkZOAQJpdKTwqMp/DQXge1vJKAeR5/ ThVPPm/zNb2xLLpfeYEeQKNcqG1kCFRXvJwJiHpulAaJiB4j61TxQCMJFcOkOXgOLQ/Z a2+HD8lIq0X8NR4IZH3ThaMkZ5BmfQlKqHdr8xVOPWzrMhVpfzKN2qoCftelTjCce5AI cymRYGgP42zU7ZsJC3GMRNkOPIaQt/cJM7bc1TnycBnTatTc0ilWK9Nq2QCTMj/6Bb4/ FtEHlXvb7Mgo1q8joQCtFHwsHZ1OiGoQ78JdVDGjNgdnJ6t86ULnbwBakvPUfdTbNOMZ Ibtg== 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=nr8mXyqoppq75z/FRAmv2PARhpMnaUiNjcYddLk+74Y=; b=hZ2zR+Ol0cRFMQZw7WKx+XtWQOir+OCEV8Utudnt3bSf7GLUKcD7fyK9nmzQglo7DZ /1TCpnpEHMiBpmoMfm4CJhzBr8pvFhy5KXjP0gMSA+h4Ia+zd9pmv1qhauilcbzjHZF7 j89mvvnnY/IbPsrHpJjHZ4OHC0UDuIGvZYgB7mtMcGbBI7Fv3Av8ap8XNFxkTDtPE7hY qwin4cYH9uyVI/hTnBV5ro9Eeuy20D6z2z+OzuTiiqe/Th36VIDBSmr94QjJZz1FVM0E HKYmj9CFxIox6DYHin/YejJjxP5hPypytWZBoLsUo1Spl2GLuiH69DYMZF22cI8RBwzd /LfQ== X-Gm-Message-State: AOAM531WhQpvIDbfJ/UZfVwR0vMYxW9ZnqM5VkX7HI5MpcLPM6dFAae/ mJsDEgbPbLjwW1QwG7m+iHJapwU/HZYzuA== X-Google-Smtp-Source: ABdhPJyOD1VNp72JmjPWa6NqIFzpjMKCPktNfzHcJvlTS4cUwujsKARM51+jzJ3ICEGDcQvZK6HI7D4IA5H6KQ== X-Received: by 2002:ad4:4152:: with SMTP id z18mr1839378qvp.42.1596601796941; Tue, 04 Aug 2020 21:29:56 -0700 (PDT) Date: Tue, 4 Aug 2020 21:29:37 -0700 In-Reply-To: <20200805042938.2961494-1-davidgow@google.com> Message-Id: <20200805042938.2961494-6-davidgow@google.com> Mime-Version: 1.0 References: <20200805042938.2961494-1-davidgow@google.com> X-Mailer: git-send-email 2.28.0.163.g6104cc2f0b6-goog Subject: [PATCH v11 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 --- 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.