[PATCH] kunit: executor: Fix a memory leak on failure in kunit_filter_tests

[PATCH] kunit: executor: Fix a memory leak on failure in kunit_filter_tests

[David Gow]

It's possible that memory allocation for the copy will fail, but for the
copy of the suite to succeed. In this case, the copy could be leaked.

Properly free 'copy' in the error case for the allocation of 'filtered'
failing.

Note that there may also have been a similar issue in
kunit_filter_subsuites, before it was removed in "kunit: flatten
kunit_suite*** to kunit_suite** in .kunit_test_suites".

This was reported by clang-analyzer via the kernel test robot, here:
https://lore.kernel.org/all/c8073b8e-7b9e-0830-4177-87c12f16349c@intel.com/

Fixes: a02353f49162 ("kunit: bail out of test filtering logic quicker if OOM")
Reported-by: kernel test robot <yujie.liu@intel.com>
Signed-off-by: David Gow <davidgow@google.com>
---
 lib/kunit/executor.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
index 6c489d6c5e5d..5e223327196a 100644
--- a/lib/kunit/executor.c
+++ b/lib/kunit/executor.c
@@ -74,8 +74,10 @@ kunit_filter_tests(const struct kunit_suite *const suite, const char *test_glob)
 		return ERR_PTR(-ENOMEM);
 
 	filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
-	if (!filtered)
+	if (!filtered) {
+		kfree(copy);
 		return ERR_PTR(-ENOMEM);
+	}
 
 	n = 0;
 	kunit_suite_for_each_test_case(suite, test_case) {
-- 
2.37.0.144.g8ac04bfd2-goog

Re: [PATCH] kunit: executor: Fix a memory leak on failure in kunit_filter_tests

[Yujie Liu]

Hi David,

On 7/12/2022 17:56, David Gow wrote:
> It's possible that memory allocation for the copy will fail, but for the

I think it is "for the _filtered_ will fail". Maybe a typo?

Thanks,
Yujie

> copy of the suite to succeed. In this case, the copy could be leaked.
> 
> Properly free 'copy' in the error case for the allocation of 'filtered'
> failing.
> 
> Note that there may also have been a similar issue in
> kunit_filter_subsuites, before it was removed in "kunit: flatten
> kunit_suite*** to kunit_suite** in .kunit_test_suites".
> 
> This was reported by clang-analyzer via the kernel test robot, here:
> https://lore.kernel.org/all/c8073b8e-7b9e-0830-4177-87c12f16349c@intel.com/
> 
> Fixes: a02353f49162 ("kunit: bail out of test filtering logic quicker if OOM")
> Reported-by: kernel test robot <yujie.liu@intel.com>
> Signed-off-by: David Gow <davidgow@google.com>
> ---
>   lib/kunit/executor.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/kunit/executor.c b/lib/kunit/executor.c
> index 6c489d6c5e5d..5e223327196a 100644
> --- a/lib/kunit/executor.c
> +++ b/lib/kunit/executor.c
> @@ -74,8 +74,10 @@ kunit_filter_tests(const struct kunit_suite *const suite, const char *test_glob)
>   		return ERR_PTR(-ENOMEM);
>   
>   	filtered = kcalloc(n + 1, sizeof(*filtered), GFP_KERNEL);
> -	if (!filtered)
> +	if (!filtered) {
> +		kfree(copy);
>   		return ERR_PTR(-ENOMEM);
> +	}
>   
>   	n = 0;
>   	kunit_suite_for_each_test_case(suite, test_case) {

Re: [PATCH] kunit: executor: Fix a memory leak on failure in kunit_filter_tests

[Daniel Latypov]

On Tue, Jul 12, 2022 at 2:56 AM David Gow <davidgow@google.com> wrote:
>
> It's possible that memory allocation for the copy will fail, but for the
> copy of the suite to succeed. In this case, the copy could be leaked.
>
> Properly free 'copy' in the error case for the allocation of 'filtered'
> failing.
>
> Note that there may also have been a similar issue in
> kunit_filter_subsuites, before it was removed in "kunit: flatten
> kunit_suite*** to kunit_suite** in .kunit_test_suites".
>
> This was reported by clang-analyzer via the kernel test robot, here:
> https://lore.kernel.org/all/c8073b8e-7b9e-0830-4177-87c12f16349c@intel.com/
>
> Fixes: a02353f49162 ("kunit: bail out of test filtering logic quicker if OOM")
> Reported-by: kernel test robot <yujie.liu@intel.com>
> Signed-off-by: David Gow <davidgow@google.com>

Reviewed-by: Daniel Latypov <dlatypov@google.com>

Thanks for taking care of this.

Re: [PATCH] kunit: executor: Fix a memory leak on failure in kunit_filter_tests

[Brendan Higgins]

On Tue, Jul 12, 2022 at 5:56 AM David Gow <davidgow@google.com> wrote:
>
> It's possible that memory allocation for the copy will fail, but for the
> copy of the suite to succeed. In this case, the copy could be leaked.
>
> Properly free 'copy' in the error case for the allocation of 'filtered'
> failing.
>
> Note that there may also have been a similar issue in
> kunit_filter_subsuites, before it was removed in "kunit: flatten
> kunit_suite*** to kunit_suite** in .kunit_test_suites".
>
> This was reported by clang-analyzer via the kernel test robot, here:
> https://lore.kernel.org/all/c8073b8e-7b9e-0830-4177-87c12f16349c@intel.com/
>
> Fixes: a02353f49162 ("kunit: bail out of test filtering logic quicker if OOM")
> Reported-by: kernel test robot <yujie.liu@intel.com>
> Signed-off-by: David Gow <davidgow@google.com>

Reviewed-by: Brendan Higgins <brendanhiggins@google.com>