From patchwork Fri Jul 31 04:42:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 11694075 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 151351392 for ; Fri, 31 Jul 2020 04:43:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id EF6DC21744 for ; Fri, 31 Jul 2020 04:43:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="PzMkVTq1" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730158AbgGaEnK (ORCPT ); Fri, 31 Jul 2020 00:43:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:45370 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730168AbgGaEnI (ORCPT ); Fri, 31 Jul 2020 00:43:08 -0400 Received: from mail-yb1-xb49.google.com (mail-yb1-xb49.google.com [IPv6:2607:f8b0:4864:20::b49]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 99C21C061575 for ; Thu, 30 Jul 2020 21:43:08 -0700 (PDT) Received: by mail-yb1-xb49.google.com with SMTP id z5so21107206ybo.9 for ; Thu, 30 Jul 2020 21:43:08 -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=BW8tJXunVDhJUT5XRrBOJfZjcR8xNS1VRsDjHnpq2UQ=; b=PzMkVTq10D01+nFN0V52eFmLisb/U/VEBWan8hJsJnThbAngryHxl38SbnKMApQ6qW PdabAwkR9xbxtvheieCsaIlOzrUP6Teis45mKc7ur9HBY9UaIgwwhiY3GrGX4KG7fRis 4BdBKiHTuT0clu1HgySJZcRY9XVk2go5BaQ8/0Wa63HGGKk/aXh1bM0uTCKejvlU4SzT ohMrA2PNPdWUBDBtLN45Lib/QMo3nKcNY5haiVtlHkBWYFxXGwcG+aJvVIomQKKbTIVv nAfJxnc6acozGQ8jdBijukd5XX//IL8LwykdEsbnn522DJOLQ8wphwFxyEz/Qmv+YOPQ nSNQ== 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=BW8tJXunVDhJUT5XRrBOJfZjcR8xNS1VRsDjHnpq2UQ=; b=g0+mSjnubKqrKsNaSTEhPQtC7ONVlCSOvDkdsseeHc7g/IBF2MgHbUdf1phyenkN7h b9JzjqrkbJCZ+XZnG0Y9ovcdQNHtdkgZHjdirYpP7RUdy3NahZmctEiwJNm+WY1DJi6W EoFjqIqU182b/T96MMkNa9YdwlCnu4JfhfjPSJ1X0AVXDiTLalFCCn4dq5AAb1InflEB DiXVTZnSARNnH8PUPMJCrAKLS4K0vTB7P3zzFEyx131Yf4TmRNEF3xZXinKPa4xCeLja O97wXde3GlutmZzzQRZbwspYEe3/Vzhxfur3kryXuVLpp+42dRwHV2foghgTyR1BAxUP jmzQ== X-Gm-Message-State: AOAM531VCt4xhbYj5VoFuqgE0JdVjEwWfkGEKLypXbuKgtOTplwJdn1U 8gt4BHkFpMuIyXjOSJMjRvy0+cxg0smFHw== X-Google-Smtp-Source: ABdhPJyYVIzaRc4aBuc+Ee1NuoEmRVl6x9tNw+147D/G2kf68oji9oeoR4JZ1I0m72B9SUwdn0JErt2a5Zxunw== X-Received: by 2002:a25:aaf3:: with SMTP id t106mr3273322ybi.56.1596170587795; Thu, 30 Jul 2020 21:43:07 -0700 (PDT) Date: Thu, 30 Jul 2020 21:42:41 -0700 In-Reply-To: <20200731044242.1323143-1-davidgow@google.com> Message-Id: <20200731044242.1323143-5-davidgow@google.com> Mime-Version: 1.0 References: <20200731044242.1323143-1-davidgow@google.com> X-Mailer: git-send-email 2.28.0.163.g6104cc2f0b6-goog Subject: [PATCH v9 4/5] 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 Cc: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.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 c652d740735d..1f9a75df0fc8 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.