From patchwork Thu Apr 2 20:46:37 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Patricia Alfonso X-Patchwork-Id: 11471597 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 1C22A92A for ; Thu, 2 Apr 2020 20:46:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id EE5B220BED for ; Thu, 2 Apr 2020 20:46:51 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="uQMfb0xx" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388621AbgDBUqu (ORCPT ); Thu, 2 Apr 2020 16:46:50 -0400 Received: from mail-pl1-f201.google.com ([209.85.214.201]:35640 "EHLO mail-pl1-f201.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731783AbgDBUqu (ORCPT ); Thu, 2 Apr 2020 16:46:50 -0400 Received: by mail-pl1-f201.google.com with SMTP id a8so3614278plm.2 for ; Thu, 02 Apr 2020 13:46:48 -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=u9tYGbzZUoeKacfHKj+okUgzHoM8x17MGKsRKBVzF6I=; b=uQMfb0xxAIExjb63NAfWbxNzX58IUh4kx7YoqwNgrBWsfj/lhHMrIdkYIx2al0nsxy UfqRTHYpcFcUV6WBrfwFPIEe+gJwjPlDCB3FPhqVw72U09ICHXpJxPv5jaaTW1L2PpKI X0G1XL7JYM+UcxPWcjBFn/2eVGMHfwjdjTCjip/S1RIaycD23/Gax6iURzYDzAgLWPzk saCWrOIIbKhsXSlG1gus8JbBGskce9oOFzvRPtS6bVs7vSd+LVY9Mszb5Y7jVfkRpMGj b0H1AyBceSSYEILo57evwEUZ011Z/GKyREZAbPrWgrldD31hVWpN560HYE1wCITA6FvP wv2w== 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=u9tYGbzZUoeKacfHKj+okUgzHoM8x17MGKsRKBVzF6I=; b=eq7zIiP9E7powHK8LDljtc44DZwn8pRr5/l0PyuOONNn89ZDliwsuBLwSQ4aGU/vvk xoxl1mhsEZBaj+NSgwVGztjzUDu0K9Vam7UT8FJOEu2vmOsmHsbhc/S1C0YZMXRhcUbQ aoMCz7XWCIrjtoTX56ZfAHHQTmfV6/JmvI7OrURhEGjcs7CMn/75bj/iXDIrhj/FtuLt tR6IZ5G+8ngw+qO2/VoxD5CS0luPJDG0HI1ra0qf731rzdhuLQNcsWHAK0e0tSD/RBit sgGDpv0+vB5P6wPOe/HdXQLOo7/pVOEkMUijRr8BhG133zN7ju7iDrHULSeHhcEnAMq4 9XEw== X-Gm-Message-State: AGi0PuaVLsOLEDS5/27YOtfr0dhRLBY+uSdxPSSiMhh+zkjxtcupX8mQ kYOoODHhVf6AzHyNvGpFHbkchOHDoeP6uJEuP5Q= X-Google-Smtp-Source: APiQypLt8J4TrsEIIQmwcI8PNHLIDMU2NUDRIAyuTZFgrBUPPoV3kJF3jVa/J06xQbLRVn+3EFvxF8aGXrT1NlncZ0Y= X-Received: by 2002:a17:90a:2663:: with SMTP id l90mr5314572pje.188.1585860408019; Thu, 02 Apr 2020 13:46:48 -0700 (PDT) Date: Thu, 2 Apr 2020 13:46:37 -0700 In-Reply-To: <20200402204639.161637-1-trishalfonso@google.com> Message-Id: <20200402204639.161637-3-trishalfonso@google.com> Mime-Version: 1.0 References: <20200402204639.161637-1-trishalfonso@google.com> X-Mailer: git-send-email 2.26.0.292.g33ef6b2f38-goog Subject: [PATCH v4 4/4] KASAN: Testing Documentation From: Patricia Alfonso To: davidgow@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 Cc: linux-kernel@vger.kernel.org, kasan-dev@googlegroups.com, kunit-dev@googlegroups.com, linux-kselftest@vger.kernel.org, Patricia Alfonso Sender: linux-kselftest-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Include documentation on how to test KASAN using CONFIG_TEST_KASAN and CONFIG_TEST_KASAN_USER. Signed-off-by: Patricia Alfonso Reviewed-by: Dmitry Vyukov --- 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..287ba063d9f6 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_TEST_KASAN & CONFIG_TEST_KASAN_USER +------------------------------------------- + +``CONFIG_TEST_KASAN`` 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`` built-in, ``CONFIG_TEST_KASAN`` 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_TEST_KASAN`` 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_TEST_KASAN`` 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_USER`` 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_USER`` 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.