[PATCH v3] media: allegro: add missed checks in allegro_open()

[Chuhong Yuan]

allegro_open() misses checks for v4l2_m2m_ctx_init() and results of
v4l2_ctrl_new* calls.
Add checks and error handlers to fix the problems.

Signed-off-by: Chuhong Yuan <hslester96@xxxxxxxxx>
---
Changes in v3:
  - Make code cleaner.
  - Add a check for handler->error.

 .../staging/media/allegro-dvt/allegro-core.c  | 24 +++++++++++++++----
 1 file changed, 20 insertions(+), 4 deletions(-)

diff --git a/drivers/staging/media/allegro-dvt/allegro-core.c b/drivers/staging/media/allegro-dvt/allegro-core.c
index 6f0cd0784786..e86001e42963 100644
--- a/drivers/staging/media/allegro-dvt/allegro-core.c
+++ b/drivers/staging/media/allegro-dvt/allegro-core.c
@@ -2270,15 +2270,12 @@ static int allegro_open(struct file *file)
 	struct allegro_channel *channel = NULL;
 	struct v4l2_ctrl_handler *handler;
 	u64 mask;
+	int ret;
 
 	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
 	if (!channel)
 		return -ENOMEM;
 
-	v4l2_fh_init(&channel->fh, vdev);
-	file->private_data = &channel->fh;
-	v4l2_fh_add(&channel->fh);
-
 	init_completion(&channel->completion);
 
 	channel->dev = dev;
@@ -2328,6 +2325,11 @@ static int allegro_open(struct file *file)
 			V4L2_CID_MIN_BUFFERS_FOR_OUTPUT,
 			1, 32,
 			1, 1);
+	if (handler->error != 0) {
+		ret = handler->error;
+		goto error;
+	}
+
 	channel->fh.ctrl_handler = handler;
 
 	channel->mcu_channel_id = -1;
@@ -2341,7 +2343,21 @@ static int allegro_open(struct file *file)
 	channel->fh.m2m_ctx = v4l2_m2m_ctx_init(dev->m2m_dev, channel,
 						allegro_queue_init);
 
+	if (IS_ERR(channel->fh.m2m_ctx)) {
+		ret = PTR_ERR(channel->fh.m2m_ctx);
+		goto error;
+	}
+
+	v4l2_fh_init(&channel->fh, vdev);
+	file->private_data = &channel->fh;
+	v4l2_fh_add(&channel->fh);
+
 	return 0;
+
+error:
+	v4l2_ctrl_handler_free(handler);
+	kfree(channel);
+	return ret;
 }
 
 static int allegro_release(struct file *file)
-- 
2.24.1