examples/io_uring-cp: fix a NULL pointer dereference

In case malloc fails, the fix returns NULL to avoid NULL pointer
dereference.

Signed-off-by: zhangliguang <zhangliguang@linux.alibaba.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

1 files changed, 7 insertions, 2 deletions

diff --git a/examples/io_uring-cp.c b/examples/io_uring-cp.c
index 1dd20fc..97f61aa 100644
--- a/examples/io_uring-cp.c
+++ b/examples/io_uring-cp.c
@@ -81,11 +81,16 @@ static int queue_read(struct io_uring *ring, off_t size, off_t offset)
 	struct io_uring_sqe *sqe;
 	struct io_data *data;
 
+	data = malloc(size + sizeof(*data));
+	if (!data)
+		return 1;
+
 	sqe = io_uring_get_sqe(ring);
-	if (!sqe)
+	if (!sqe) {
+		free(data);
 		return 1;
+	}
 
-	data = malloc(size + sizeof(*data));
 	data->read = 1;
 	data->offset = data->first_offset = offset;