kasan: add macros to simplify checking test constraints

Some KASAN tests require specific kernel configs to be enabled.
Instead of copy-pasting the checks for these configs add a few helper
macros and use them.

Link: https://linux-review.googlesource.com/id/I237484a7fddfedf4a4aae9cc61ecbcdbe85a0a63
Link: https://lkml.kernel.org/r/6a0fcdb9676b7e869cfc415893ede12d916c246c.1610733117.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Suggested-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Branislav Rankov <Branislav.Rankov@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Evgenii Stepanov <eugenis@google.com>
Cc: Kevin Brodsky <kevin.brodsky@arm.com>
Cc: Peter Collingbourne <pcc@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 31 insertions, 70 deletions

diff --git a/lib/test_kasan.c b/lib/test_kasan.c
index 6f46e27c2af7..714ea27fcc3e 100644
--- a/lib/test_kasan.c
+++ b/lib/test_kasan.c
@@ -73,6 +73,20 @@ static void kasan_test_exit(struct kunit *test)
 			fail_data.report_found); \
 } while (0)
 
+#define KASAN_TEST_NEEDS_CONFIG_ON(test, config) do {			\
+	if (!IS_ENABLED(config)) {					\
+		kunit_info((test), "skipping, " #config " required");	\
+		return;							\
+	}								\
+} while (0)
+
+#define KASAN_TEST_NEEDS_CONFIG_OFF(test, config) do {			\
+	if (IS_ENABLED(config)) {					\
+		kunit_info((test), "skipping, " #config " enabled");	\
+		return;							\
+	}								\
+} while (0)
+
 static void kmalloc_oob_right(struct kunit *test)
 {
 	char *ptr;
@@ -114,10 +128,7 @@ static void kmalloc_pagealloc_oob_right(struct kunit *test)
 	char *ptr;
 	size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
 
-	if (!IS_ENABLED(CONFIG_SLUB)) {
-		kunit_info(test, "CONFIG_SLUB is not enabled.");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB);
 
 	/*
 	 * Allocate a chunk that does not fit into a SLUB cache to trigger
@@ -135,10 +146,7 @@ static void kmalloc_pagealloc_uaf(struct kunit *test)
 	char *ptr;
 	size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
 
-	if (!IS_ENABLED(CONFIG_SLUB)) {
-		kunit_info(test, "CONFIG_SLUB is not enabled.");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB);
 
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
@@ -152,10 +160,7 @@ static void kmalloc_pagealloc_invalid_free(struct kunit *test)
 	char *ptr;
 	size_t size = KMALLOC_MAX_CACHE_SIZE + 10;
 
-	if (!IS_ENABLED(CONFIG_SLUB)) {
-		kunit_info(test, "CONFIG_SLUB is not enabled.");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_SLUB);
 
 	ptr = kmalloc(size, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
@@ -218,10 +223,7 @@ static void kmalloc_oob_16(struct kunit *test)
 	} *ptr1, *ptr2;
 
 	/* This test is specifically crafted for the generic mode. */
-	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_GENERIC required\n");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC);
 
 	ptr1 = kmalloc(sizeof(*ptr1) - 3, GFP_KERNEL);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr1);
@@ -454,10 +456,7 @@ static void kasan_global_oob(struct kunit *test)
 	char *p = &global_array[ARRAY_SIZE(global_array) + i];
 
 	/* Only generic mode instruments globals. */
-	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_GENERIC required");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC);
 
 	KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
 }
@@ -486,10 +485,7 @@ static void kasan_stack_oob(struct kunit *test)
 	volatile int i = OOB_TAG_OFF;
 	char *p = &stack_array[ARRAY_SIZE(stack_array) + i];
 
-	if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
-		kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK);
 
 	KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
 }
@@ -501,15 +497,8 @@ static void kasan_alloca_oob_left(struct kunit *test)
 	char *p = alloca_array - 1;
 
 	/* Only generic mode instruments dynamic allocas. */
-	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_GENERIC required");
-		return;
-	}
-
-	if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
-		kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC);
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK);
 
 	KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
 }
@@ -521,15 +510,8 @@ static void kasan_alloca_oob_right(struct kunit *test)
 	char *p = alloca_array + i;
 
 	/* Only generic mode instruments dynamic allocas. */
-	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_GENERIC required");
-		return;
-	}
-
-	if (!IS_ENABLED(CONFIG_KASAN_STACK)) {
-		kunit_info(test, "CONFIG_KASAN_STACK is not enabled");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC);
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_STACK);
 
 	KUNIT_EXPECT_KASAN_FAIL(test, *(volatile char *)p);
 }
@@ -593,11 +575,7 @@ static void kasan_memchr(struct kunit *test)
 	 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
 	 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
 	 */
-	if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
-		kunit_info(test,
-			"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT);
 
 	if (OOB_TAG_OFF)
 		size = round_up(size, OOB_TAG_OFF);
@@ -621,11 +599,7 @@ static void kasan_memcmp(struct kunit *test)
 	 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
 	 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
 	 */
-	if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
-		kunit_info(test,
-			"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT);
 
 	if (OOB_TAG_OFF)
 		size = round_up(size, OOB_TAG_OFF);
@@ -648,11 +622,7 @@ static void kasan_strings(struct kunit *test)
 	 * str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT.
 	 * See https://bugzilla.kernel.org/show_bug.cgi?id=206337 for details.
 	 */
-	if (IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT)) {
-		kunit_info(test,
-			"str* functions are not instrumented with CONFIG_AMD_MEM_ENCRYPT");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_AMD_MEM_ENCRYPT);
 
 	ptr = kmalloc(size, GFP_KERNEL | __GFP_ZERO);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ptr);
@@ -713,10 +683,7 @@ static void kasan_bitops_generic(struct kunit *test)
 	long *bits;
 
 	/* This test is specifically crafted for the generic mode. */
-	if (!IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_GENERIC required\n");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_GENERIC);
 
 	/*
 	 * Allocate 1 more byte, which causes kzalloc to round up to 16 bytes;
@@ -744,11 +711,8 @@ static void kasan_bitops_tags(struct kunit *test)
 {
 	long *bits;
 
-	/* This test is specifically crafted for the tag-based mode. */
-	if (IS_ENABLED(CONFIG_KASAN_GENERIC)) {
-		kunit_info(test, "CONFIG_KASAN_SW_TAGS required\n");
-		return;
-	}
+	/* This test is specifically crafted for tag-based modes. */
+	KASAN_TEST_NEEDS_CONFIG_OFF(test, CONFIG_KASAN_GENERIC);
 
 	/* Allocation size will be rounded to up granule size, which is 16. */
 	bits = kzalloc(sizeof(*bits), GFP_KERNEL);
@@ -777,10 +741,7 @@ static void vmalloc_oob(struct kunit *test)
 {
 	void *area;
 
-	if (!IS_ENABLED(CONFIG_KASAN_VMALLOC)) {
-		kunit_info(test, "CONFIG_KASAN_VMALLOC is not enabled.");
-		return;
-	}
+	KASAN_TEST_NEEDS_CONFIG_ON(test, CONFIG_KASAN_VMALLOC);
 
 	/*
 	 * We have to be careful not to hit the guard page.