[media] cx25840: fix unchecked return values

In functions cx25840_initialize(), cx231xx_initialize(), and
cx23885_initialize(), the return value of create_singlethread_workqueue()
is used without validation. This may result in NULL dereference and cause
kernel crash. This patch fixes it.

Signed-off-by: Pan Bian <bianpan2016@163.com>
Signed-off-by: Hans Verkuil <hans.verkuil@cisco.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@s-opensource.com>
This commit is contained in:
Pan Bian 2017-04-23 10:06:36 -03:00 committed by Mauro Carvalho Chehab
parent b9150e8131
commit 35378ce143

View File

@ -416,11 +416,13 @@ static void cx25840_initialize(struct i2c_client *client)
INIT_WORK(&state->fw_work, cx25840_work_handler);
init_waitqueue_head(&state->fw_wait);
q = create_singlethread_workqueue("cx25840_fw");
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
if (q) {
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
}
/* 6. */
cx25840_write(client, 0x115, 0x8c);
@ -630,11 +632,13 @@ static void cx23885_initialize(struct i2c_client *client)
INIT_WORK(&state->fw_work, cx25840_work_handler);
init_waitqueue_head(&state->fw_wait);
q = create_singlethread_workqueue("cx25840_fw");
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
if (q) {
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
}
/* Call the cx23888 specific std setup func, we no longer rely on
* the generic cx24840 func.
@ -748,11 +752,13 @@ static void cx231xx_initialize(struct i2c_client *client)
INIT_WORK(&state->fw_work, cx25840_work_handler);
init_waitqueue_head(&state->fw_wait);
q = create_singlethread_workqueue("cx25840_fw");
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
if (q) {
prepare_to_wait(&state->fw_wait, &wait, TASK_UNINTERRUPTIBLE);
queue_work(q, &state->fw_work);
schedule();
finish_wait(&state->fw_wait, &wait);
destroy_workqueue(q);
}
cx25840_std_setup(client);