[PATCH] drm/tests: shmem: Fix memleak

[PATCH] drm/tests: shmem: Fix memleak

[Maxime Ripard]

The drm_gem_shmem_test_get_pages_sgt() gets a scatter-gather table using
the drm_gem_shmem_get_sg_table() function and rightfully calls
sg_free_table() on it. However, it's also supposed to kfree() the
returned sg_table, but doesn't.

This leads to a memory leak, reported by kmemleak. Fix it by adding a
kunit action to kfree the sgt when the test ends.

Reported-by: Philipp Stanner <phasta@mailbox.org>
Closes: https://lore.kernel.org/dri-devel/a7655158a6367ac46194d57f4b7433ef0772a73e.camel@mailbox.org/
Fixes: 93032ae634d4 ("drm/test: add a test suite for GEM objects backed by shmem")
Signed-off-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/tests/drm_gem_shmem_test.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_gem_shmem_test.c b/drivers/gpu/drm/tests/drm_gem_shmem_test.c
index fd4215e2f982..925fbc2cda70 100644
--- a/drivers/gpu/drm/tests/drm_gem_shmem_test.c
+++ b/drivers/gpu/drm/tests/drm_gem_shmem_test.c
@@ -214,10 +214,13 @@ static void drm_gem_shmem_test_get_pages_sgt(struct kunit *test)
 
 	sgt = drm_gem_shmem_get_sg_table(shmem);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, sgt);
 	KUNIT_EXPECT_NULL(test, shmem->sgt);
 
+	ret = kunit_add_action_or_reset(test, kfree_wrapper, sgt);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
 	ret = kunit_add_action_or_reset(test, sg_free_table_wrapper, sgt);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	for_each_sgtable_sg(sgt, sg, si) {
 		KUNIT_EXPECT_NOT_NULL(test, sg);
-- 
2.49.0

Re: [PATCH] drm/tests: shmem: Fix memleak

[Javier Martinez Canillas]

Maxime Ripard <mripard@kernel.org> writes:

Hello Maxime,

> The drm_gem_shmem_test_get_pages_sgt() gets a scatter-gather table using
> the drm_gem_shmem_get_sg_table() function and rightfully calls
> sg_free_table() on it. However, it's also supposed to kfree() the
> returned sg_table, but doesn't.
>
> This leads to a memory leak, reported by kmemleak. Fix it by adding a
> kunit action to kfree the sgt when the test ends.
>
> Reported-by: Philipp Stanner <phasta@mailbox.org>
> Closes: https://lore.kernel.org/dri-devel/a7655158a6367ac46194d57f4b7433ef0772a73e.camel@mailbox.org/
> Fixes: 93032ae634d4 ("drm/test: add a test suite for GEM objects backed by shmem")
> Signed-off-by: Maxime Ripard <mripard@kernel.org>
> ---

Reviewed-by: Javier Martinez Canillas <javierm@redhat.com>

-- 
Best regards,

Javier Martinez Canillas
Core Platforms
Red Hat

Re: [PATCH] drm/tests: shmem: Fix memleak

[Maxime Ripard]

On Tue, 08 Apr 2025 16:07:58 +0200, Maxime Ripard wrote:
> The drm_gem_shmem_test_get_pages_sgt() gets a scatter-gather table using
> the drm_gem_shmem_get_sg_table() function and rightfully calls
> sg_free_table() on it. However, it's also supposed to kfree() the
> returned sg_table, but doesn't.
> 
> This leads to a memory leak, reported by kmemleak. Fix it by adding a
> kunit action to kfree the sgt when the test ends.
> 
> [...]

Applied to misc/kernel.git (drm-misc-fixes).

Thanks!
Maxime