Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
From:   Kees Cook <keescook@chromium.org>
To:     linux-hardening@vger.kernel.org
Cc:     Kees Cook <keescook@chromium.org>, Kees Cook <kees@outflux.net>,
        Andy Shevchenko <andy@kernel.org>,
        Cezary Rojewski <cezary.rojewski@intel.com>,
        Puyou Lu <puyou.lu@gmail.com>, Mark Brown <broonie@kernel.org>,
        Josh Poimboeuf <jpoimboe@kernel.org>,
        Peter Zijlstra <peterz@infradead.org>,
        Brendan Higgins <brendan.higgins@linux.dev>,
        David Gow <davidgow@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Alexander Potapenko <glider@google.com>,
        Zhaoyang Huang <zhaoyang.huang@unisoc.com>,
        Randy Dunlap <rdunlap@infradead.org>,
        Geert Uytterhoeven <geert+renesas@glider.be>,
        Miguel Ojeda <ojeda@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Liam Howlett <liam.howlett@oracle.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        Dan Williams <dan.j.williams@intel.com>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Yury Norov <yury.norov@gmail.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Sander Vanheule <sander@svanheule.net>,
        Eric Biggers <ebiggers@google.com>,
        "Masami Hiramatsu (Google)" <mhiramat@kernel.org>,
        Andrey Konovalov <andreyknvl@gmail.com>,
        Linus Walleij <linus.walleij@linaro.org>,
        Daniel Latypov <dlatypov@google.com>,
        =?UTF-8?q?Jos=C3=A9=20Exp=C3=B3sito?= <jose.exposito89@gmail.com>,
        linux-kernel@vger.kernel.org, kunit-dev@googlegroups.com
Subject: [PATCH 2/9] fortify: Allow KUnit test to build without FORTIFY
Date:   Wed,  5 Apr 2023 17:02:01 -0700
Message-Id: <20230406000212.3442647-2-keescook@chromium.org>
In-Reply-To: <20230405235832.never.487-kees@kernel.org>
References: <20230405235832.never.487-kees@kernel.org>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

From: Kees Cook <kees@outflux.net>

In order for CI systems to notice all the skipped tests related to
CONFIG_FORTIFY_SOURCE, allow the FORTIFY_SOURCE KUnit tests to build
with or without CONFIG_FORTIFY_SOURCE.

Signed-off-by: Kees Cook <kees@outflux.net>
---
 lib/Kconfig.debug   |  2 +-
 lib/fortify_kunit.c | 15 +++++++++++++++
 2 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c8b379e2e9ad..d48a5f4b471e 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2614,7 +2614,7 @@ config STACKINIT_KUNIT_TEST
 
 config FORTIFY_KUNIT_TEST
 	tristate "Test fortified str*() and mem*() function internals at runtime" if !KUNIT_ALL_TESTS
-	depends on KUNIT && FORTIFY_SOURCE
+	depends on KUNIT
 	default KUNIT_ALL_TESTS
 	help
 	  Builds unit tests for checking internals of FORTIFY_SOURCE as used
diff --git a/lib/fortify_kunit.c b/lib/fortify_kunit.c
index c8c33cbaae9e..d054fc20a7d5 100644
--- a/lib/fortify_kunit.c
+++ b/lib/fortify_kunit.c
@@ -25,8 +25,21 @@ static const char array_of_10[] = "this is 10";
 static const char *ptr_of_11 = "this is 11!";
 static char array_unknown[] = "compiler thinks I might change";
 
+/* Handle being built without CONFIG_FORTIFY_SOURCE */
+#ifndef __compiletime_strlen
+# define __compiletime_strlen __builtin_strlen
+#endif
+
+#define skip_without_fortify()	\
+do {				\
+	if (!IS_ENABLED(CONFIG_FORTIFY_SOURCE))	\
+		kunit_skip(test, "Not built with CONFIG_FORTIFY_SOURCE=y"); \
+} while (0)
+
 static void known_sizes_test(struct kunit *test)
 {
+	skip_without_fortify();
+
 	KUNIT_EXPECT_EQ(test, __compiletime_strlen("88888888"), 8);
 	KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_of_10), 10);
 	KUNIT_EXPECT_EQ(test, __compiletime_strlen(ptr_of_11), 11);
@@ -60,6 +73,8 @@ static noinline size_t want_minus_one(int pick)
 
 static void control_flow_split_test(struct kunit *test)
 {
+	skip_without_fortify();
+
 	KUNIT_EXPECT_EQ(test, want_minus_one(pick), SIZE_MAX);
 }
 
-- 
2.34.1