ALSA: core: Fix possible NULL dereference caused by kunit_kzalloc()

kunit_kzalloc() may return a NULL pointer, dereferencing it without
NULL check may lead to NULL dereference.
Add NULL checks for all the kunit_kzalloc() in sound_kunit.c

Fixes: 3e39acf ("ALSA: core: Add sound core KUnit test")
Signed-off-by: Zichen Xie <zichenxie0106@gmail.com>
Link: https://patch.msgid.link/20241126192448.12645-1-zichenxie0106@gmail.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>

Author: Gax-c

sound/core/sound_kunit.c

@@ -172,6 +172,7 @@ static void test_format_fill_silence(struct kunit *test)
 	u32 i, j;
 
 	buffer = kunit_kzalloc(test, SILENCE_BUFFER_SIZE, GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buffer);
 
 	for (i = 0; i < ARRAY_SIZE(buf_samples); i++) {
 		for (j = 0; j < ARRAY_SIZE(valid_fmt); j++)
@@ -208,8 +209,12 @@ static void test_playback_avail(struct kunit *test)
 	struct snd_pcm_runtime *r = kunit_kzalloc(test, sizeof(*r), GFP_KERNEL);
 	u32 i;
 
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r);
+
 	r->status = kunit_kzalloc(test, sizeof(*r->status), GFP_KERNEL);
 	r->control = kunit_kzalloc(test, sizeof(*r->control), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r->status);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r->control);
 
 	for (i = 0; i < ARRAY_SIZE(p_avail_data); i++) {
 		r->buffer_size = p_avail_data[i].buffer_size;
@@ -232,8 +237,12 @@ static void test_capture_avail(struct kunit *test)
 	struct snd_pcm_runtime *r = kunit_kzalloc(test, sizeof(*r), GFP_KERNEL);
 	u32 i;
 
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r);
+
 	r->status = kunit_kzalloc(test, sizeof(*r->status), GFP_KERNEL);
 	r->control = kunit_kzalloc(test, sizeof(*r->control), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r->status);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, r->control);
 
 	for (i = 0; i < ARRAY_SIZE(c_avail_data); i++) {
 		r->buffer_size = c_avail_data[i].buffer_size;
@@ -247,6 +256,7 @@ static void test_capture_avail(struct kunit *test)
 static void test_card_set_id(struct kunit *test)
 {
 	struct snd_card *card = kunit_kzalloc(test, sizeof(*card), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, card);
 
 	snd_card_set_id(card, VALID_NAME);
 	KUNIT_EXPECT_STREQ(test, card->id, VALID_NAME);
@@ -280,6 +290,7 @@ static void test_pcm_format_name(struct kunit *test)
 static void test_card_add_component(struct kunit *test)
 {
 	struct snd_card *card = kunit_kzalloc(test, sizeof(*card), GFP_KERNEL);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, card);
 
 	snd_component_add(card, TEST_FIRST_COMPONENT);
 	KUNIT_ASSERT_STREQ(test, card->components, TEST_FIRST_COMPONENT);