[PATCH 5.14 125/169] kunit: fix reference count leak in kfree_at_end

Greg Kroah-Hartman
2021-10-25T19:56:47Z

From: Xiyu Yang <xiyuyang19@fudan.edu.cn>

[ Upstream commit f62314b1ced25c58b86e044fc951cd6a1ea234cf ]

The reference counting issue happens in the normal path of
kfree_at_end(). When kunit_alloc_and_get_resource() is invoked, the
function forgets to handle the returned resource object, whose refcount
increased inside, causing a refcount leak.

Fix this issue by calling kunit_alloc_resource() instead of
kunit_alloc_and_get_resource().

Fixed the following when applying:
Shuah Khan <skhan@linuxfoundation.org>

CHECK: Alignment should match open parenthesis
+ kunit_alloc_resource(test, NULL, kfree_res_free, GFP_KERNEL,
(void *)to_free);

Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Reviewed-by: Daniel Latypov <dlatypov@google.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
lib/kunit/executor_test.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/kunit/executor_test.c b/lib/kunit/executor_test.c
index cdbe54b16501..e14a18af573d 100644
--- a/lib/kunit/executor_test.c
+++ b/lib/kunit/executor_test.c
@@ -116,8 +116,8 @@ static void kfree_at_end(struct kunit *test, const void *to_free)
/* kfree() handles NULL already, but avoid allocating a no-op cleanup. */
if (IS_ERR_OR_NULL(to_free))
return;
- kunit_alloc_and_get_resource(test, NULL, kfree_res_free, GFP_KERNEL,
- (void *)to_free);
+ kunit_alloc_resource(test, NULL, kfree_res_free, GFP_KERNEL,
+ (void *)to_free);
}

static struct kunit_suite *alloc_fake_suite(struct kunit *test,
--
2.33.0