From patchwork Fri Apr 24 06:13:41 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 11507161 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 0CB4D81 for ; Fri, 24 Apr 2020 06:14:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E90D220857 for ; Fri, 24 Apr 2020 06:14:07 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="ulwvVvdq" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726554AbgDXGOH (ORCPT ); Fri, 24 Apr 2020 02:14:07 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49898 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1725889AbgDXGOG (ORCPT ); Fri, 24 Apr 2020 02:14:06 -0400 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E12BEC09B045 for ; Thu, 23 Apr 2020 23:14:05 -0700 (PDT) Received: by mail-yb1-xb4a.google.com with SMTP id m138so2435862ybf.12 for ; Thu, 23 Apr 2020 23:14:05 -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=5epptiP6vyK9ksah1mqKRXgiRHBz5N7tvZFE7or+VcA=; b=ulwvVvdqEW+IJ4ZDJ8/ufTJ/zOyYKVP39a143BYyHnkike1p3jMupT4mYRbcDXGObR kt/ycV+2w4PE+xLdGnOd72QOFvCtb/zTp89MZBAKxwolAEK+nUufeHi1AZWm29hq6ZLE /JML3lImDzCGevk5SkhdI9IFNaCtuGfbobXCQdycrnVlghyg7LW9hskkiNHXoEiv4Q0x rmlxt8TuRi6I3Xvy2IO/59Thimn5irJyuGxgPvcAWQlnZx4fGRXe7BUbboXF7AhNN9A8 foEVvkDb5g9p+3H2LXbAwJxzam5E5LlTyqgw7/J3v5JKu+oeY0LSoSUKznBIdMx96hNW //gA== 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=5epptiP6vyK9ksah1mqKRXgiRHBz5N7tvZFE7or+VcA=; b=k71iB0z94S0HEUZao8iQZlql6QXe3v9Zi3JjbHb8s/whtBSRyRy2sd96D5UAp4WZLL 3mX6DNQbhlOdfohlt987Mryt/M7uByg7ABieehamk7reSB4616p6mlOIu2NOxEh5JzGh 84WR0hYHDz8o2FIFXdjjkwVQnDiEwjbnFlf/HIPGyC1c61scQb88bJZWjNK1VXIN4/TO BNTPace37MMXQP+vOW7AilnXDRHuSyLxI8PdA2pVoquVtoLzckiYJwRX+kgFQFlxU+kd JNNBSOZhKZdZ2/Reuo9C2cRIdQ7Ogc23bzuCFhmk2Gcv2F0qUDO0bpIuZg0ZNnRMsfPC a6wg== X-Gm-Message-State: AGi0PuahUEc6Zej/adv8QsQPezoJr3VBUm6XLGxusG12Kii/kMuriT1+ cwyQt/KczfqB6Yly6I0lNlfKVk/qs2eqFA== X-Google-Smtp-Source: APiQypJovP6+qI5o42bhNd8V9jsDjBcJywaFZ16qLB01QR5bZhAswW3ktdSN1KWfx+4lWLLGUYKhYpLKpM5S/w== X-Received: by 2002:a25:bd4c:: with SMTP id p12mr13287597ybm.140.1587708844982; Thu, 23 Apr 2020 23:14:04 -0700 (PDT) Date: Thu, 23 Apr 2020 23:13:41 -0700 In-Reply-To: <20200424061342.212535-1-davidgow@google.com> Message-Id: <20200424061342.212535-5-davidgow@google.com> Mime-Version: 1.0 References: <20200424061342.212535-1-davidgow@google.com> X-Mailer: git-send-email 2.26.2.303.gf8c07b1a785-goog Subject: [PATCH v7 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 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 Reviewed-by: Dmitry Vyukov Signed-off-by: David Gow Reviewed-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 c652d740735d..b4b109d88f9e 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_KUNIT & CONFIG_TEST_KASAN_MODULE +-------------------------------------------------- + +``CONFIG_TEST_KASAN_KUNIT`` 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_TEST_KASAN_KUNIT`` 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_KUNIT`` 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_KUNIT`` 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.