on 3/13/2025 8:00 AM, Qasim Ijaz wrote:
> test_mb_mark_used() and test_mb_free_blocks() call kunit_kzalloc() to
> allocate memory, however both fail to ensure that the allocations
> succeeded. If kunit_kzalloc() returns NULL, then dereferencing the
> corresponding pointer without checking for NULL will lead to
> a NULL pointer dereference.
>
> To fix this call KUNIT_ASSERT_NOT_ERR_OR_NULL() to ensure
> the allocation succeeded.
Reviewed-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx>
>
> Fixes: ac96b56a2fbd ("ext4: Add unit test for mb_mark_used")
> Fixes: b7098e1fa7bc ("ext4: Add unit test for mb_free_blocks")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Qasim Ijaz <qasdev00@xxxxxxxxx>
> ---
> fs/ext4/mballoc-test.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/fs/ext4/mballoc-test.c b/fs/ext4/mballoc-test.c
> index bb2a223b207c..d634c12f1984 100644
> --- a/fs/ext4/mballoc-test.c
> +++ b/fs/ext4/mballoc-test.c
> @@ -796,6 +796,7 @@ static void test_mb_mark_used(struct kunit *test)
> KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buddy);
> grp = kunit_kzalloc(test, offsetof(struct ext4_group_info,
> bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, grp);
>
> ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
> KUNIT_ASSERT_EQ(test, ret, 0);
> @@ -860,6 +861,7 @@ static void test_mb_free_blocks(struct kunit *test)
> KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buddy);
> grp = kunit_kzalloc(test, offsetof(struct ext4_group_info,
> bb_counters[MB_NUM_ORDERS(sb)]), GFP_KERNEL);
> + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, grp);
>
> ret = ext4_mb_load_buddy(sb, TEST_GOAL_GROUP, &e4b);
> KUNIT_ASSERT_EQ(test, ret, 0);
>
