From patchwork Tue Apr 14 03:16:48 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Gow X-Patchwork-Id: 11486619 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 758F015AB for ; Tue, 14 Apr 2020 03:18:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 5CCEE20775 for ; Tue, 14 Apr 2020 03:18:11 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CWNeHW1R" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404535AbgDNDSB (ORCPT ); Mon, 13 Apr 2020 23:18:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47350 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S2404524AbgDNDRx (ORCPT ); Mon, 13 Apr 2020 23:17:53 -0400 Received: from mail-pf1-x44a.google.com (mail-pf1-x44a.google.com [IPv6:2607:f8b0:4864:20::44a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A991EC0A3BDC for ; Mon, 13 Apr 2020 20:17:51 -0700 (PDT) Received: by mail-pf1-x44a.google.com with SMTP id o5so10596095pfp.0 for ; Mon, 13 Apr 2020 20:17:51 -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=lyafSFvaDeRHLhmsBZNecjQ1f+rw68vrQlYD5+Y3w5w=; b=CWNeHW1RO5sckHu6dLDpxyBDTx4Cg4OOH4TyzDUrypTV4Iqtnp2LvVxgZGi6ibcHVT QCFUPYNS7rg2mlXcTkM+W0ha59BbxI2NoZQqV8kznf/hB/mOnhqDOgYz/Q4x9WvxQqtP FDLd8yHlCcKguTvTvjqqlsRPy0pWzQHm99xKMK1swgEcq0WzNWfFmnhDzf4Vg4yreNIf qtegHdg9SfaSNX6m6iOTTbG5lAR7jkp0QEkwQ3ji6DonV/ZBQ0vyD36qSQQ+7U3KrxGn UqdGaHZzR7yMeeiFQoAzKLWGvyintTXYBco3E5dJE5R9jczdlO4mEPkTwVEBcwnmhOqU /Zcw== 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=lyafSFvaDeRHLhmsBZNecjQ1f+rw68vrQlYD5+Y3w5w=; b=spModQ9QKsB4lMW2uc5j7gIG71U6XAckFQi/5HHomNclTGLF4BRdeEArETwujJFPjL 7UzRzaTfdZACid8QTs5sYywnK/KmBJfRoUHTFEvJCC6Q47buAouJagK/jjHRR/DOs3ko MfwNy2Vb/RogA7R16VPgePKOfma3xb9ixBheqCbRtlrP2lOanKb/ZV8lRWg2MaONuVmz Uvn0AFfM+MHFiKmlj2BPF4vbjHDcwbuCaL2pLQEwk8GIVD/Sslo6C5GiSqspRd94o+n8 toHt6+nHuMD0n7uKfTt71/2U7q+Gpm7Ok1NxFqV67+UM6jyMSruskfiIyRsyDbduzYlo 43cg== X-Gm-Message-State: AGi0PuZZ5xnNrV/Wl82IpRNEVq9iQnkckp+nL8cM4rzpED/kB32nNXR7 oNjMTlddVRJrf1X56IoOtLTUteDnPVK2AA== X-Google-Smtp-Source: APiQypJa/aSFUd/BKg0xZ7tNeHgpbWs6EfLUQ46ZU+1HNZdQVHpeU9HKe0IRRR9LN/VkxpUAEc0tH2n31sVb8w== X-Received: by 2002:a17:90a:d101:: with SMTP id l1mr25196004pju.1.1586834271190; Mon, 13 Apr 2020 20:17:51 -0700 (PDT) Date: Mon, 13 Apr 2020 20:16:48 -0700 In-Reply-To: <20200414031647.124664-1-davidgow@google.com> Message-Id: <20200414031647.124664-5-davidgow@google.com> Mime-Version: 1.0 References: <20200414031647.124664-1-davidgow@google.com> X-Mailer: git-send-email 2.26.0.110.g2183baf09c-goog Subject: [PATCH v5 4/4] 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 and CONFIG_TEST_KASAN_USER. Signed-off-by: Patricia Alfonso Reviewed-by: Dmitry Vyukov Signed-off-by: David Gow --- 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.