[PATCH v2 5/5] kunit: make kunit_kfree(NULL) a no-op to match kfree()

From: Daniel Latypov
Date: Fri Jul 22 2022 - 13:16:07 EST


The real kfree() function will silently return when given a NULL.
So a user might reasonably think they can write the following code:
char *buffer = NULL;
if (param->use_buffer) buffer = kunit_kzalloc(test, 10, GFP_KERNEL);
...
kunit_kfree(test, buffer);

As-is, kunit_kfree() will mark the test as FAILED when buffer is NULL.
(And in earlier times, it would segfault).

Let's match the semantics of kfree().

Suggested-by: David Gow <davidgow@xxxxxxxxxx>
Signed-off-by: Daniel Latypov <dlatypov@xxxxxxxxxx>
---
v1 -> v2: add this patch to the series.
---
lib/kunit/test.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index c7ca87484968..879c8db36cb5 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -698,6 +698,9 @@ static inline bool kunit_kfree_match(struct kunit *test,

void kunit_kfree(struct kunit *test, const void *ptr)
{
+ if (!ptr)
+ return;
+
if (kunit_destroy_resource(test, kunit_kfree_match, (void *)ptr))
KUNIT_FAIL(test, "kunit_kfree: %px already freed or not allocated by kunit", ptr);
}
--
2.37.1.359.gd136c6c3e2-goog