diff options
| author | Kees Cook <kees@kernel.org> | 2025-03-11 17:03:56 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2025-03-12 13:23:52 -0700 |
| commit | 416cf1f4d91bf52305cd160a382273ccef980b7f (patch) | |
| tree | d79e53626533effbe522ce556c48998517befb1b /lib | |
| parent | d985e4399adffb58e10b38dbb5479ef29d53cde6 (diff) | |
kunit/fortify: Expand testing of __compiletime_strlen()
It seems that Clang thinks __builtin_constant_p() of undefined variables
should return true[1]. This is being fixed separately[2], but in the
meantime, expand the fortify tests to help track this kind of thing down
faster in the future.
Link: https://github.com/ClangBuiltLinux/linux/issues/2073 [1]
Link: https://github.com/llvm/llvm-project/pull/130713 [2]
Link: https://lore.kernel.org/r/20250312000349.work.786-kees@kernel.org
Signed-off-by: Kees Cook <kees@kernel.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/tests/fortify_kunit.c | 17 |
1 files changed, 17 insertions, 0 deletions
diff --git a/lib/tests/fortify_kunit.c b/lib/tests/fortify_kunit.c index ecb638d4cde1..18dcdedf777f 100644 --- a/lib/tests/fortify_kunit.c +++ b/lib/tests/fortify_kunit.c @@ -60,6 +60,7 @@ static int fortify_write_overflows; static const char array_of_10[] = "this is 10"; static const char *ptr_of_11 = "this is 11!"; +static const char * const unchanging_12 = "this is 12!!"; static char array_unknown[] = "compiler thinks I might change"; void fortify_add_kunit_error(int write) @@ -83,12 +84,28 @@ void fortify_add_kunit_error(int write) static void fortify_test_known_sizes(struct kunit *test) { + char stack[80] = "Test!"; + + KUNIT_EXPECT_FALSE(test, __is_constexpr(__builtin_strlen(stack))); + KUNIT_EXPECT_EQ(test, __compiletime_strlen(stack), 5); + + KUNIT_EXPECT_TRUE(test, __is_constexpr(__builtin_strlen("88888888"))); KUNIT_EXPECT_EQ(test, __compiletime_strlen("88888888"), 8); + + KUNIT_EXPECT_TRUE(test, __is_constexpr(__builtin_strlen(array_of_10))); KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_of_10), 10); + + KUNIT_EXPECT_FALSE(test, __is_constexpr(__builtin_strlen(ptr_of_11))); KUNIT_EXPECT_EQ(test, __compiletime_strlen(ptr_of_11), 11); + KUNIT_EXPECT_TRUE(test, __is_constexpr(__builtin_strlen(unchanging_12))); + KUNIT_EXPECT_EQ(test, __compiletime_strlen(unchanging_12), 12); + + KUNIT_EXPECT_FALSE(test, __is_constexpr(__builtin_strlen(array_unknown))); KUNIT_EXPECT_EQ(test, __compiletime_strlen(array_unknown), SIZE_MAX); + /* Externally defined and dynamically sized string pointer: */ + KUNIT_EXPECT_FALSE(test, __is_constexpr(__builtin_strlen(test->name))); KUNIT_EXPECT_EQ(test, __compiletime_strlen(test->name), SIZE_MAX); } |