re: media: i2c: add OV02A10 image sensor driver

From: Colin Ian King
Date: Thu Dec 03 2020 - 13:01:06 EST


Hi,

Static analysis on linux-next with Coverity has detected an issue with
the following commit:

529 static int ov02a10_s_stream(struct v4l2_subdev *sd, int on)
530 {
531 struct ov02a10 *ov02a10 = to_ov02a10(sd);
532 struct i2c_client *client =
v4l2_get_subdevdata(&ov02a10->subdev);

1. var_decl: Declaring variable ret without initializer.

533 int ret;
534
535 mutex_lock(&ov02a10->mutex);
536

2. Condition ov02a10->streaming == on, taking true branch.

537 if (ov02a10->streaming == on)

3. Jumping to label unlock_and_return.

538 goto unlock_and_return;
539
540 if (on) {
541 ret = pm_runtime_get_sync(&client->dev);
542 if (ret < 0) {
543 pm_runtime_put_noidle(&client->dev);
544 goto unlock_and_return;
545 }
546
547 ret = __ov02a10_start_stream(ov02a10);
548 if (ret) {
549 __ov02a10_stop_stream(ov02a10);
550 ov02a10->streaming = !on;
551 goto err_rpm_put;
552 }
553 } else {
554 __ov02a10_stop_stream(ov02a10);
555 pm_runtime_put(&client->dev);
556 }
557
558 ov02a10->streaming = on;
559 mutex_unlock(&ov02a10->mutex);
560
561 return 0;
562
563 err_rpm_put:
564 pm_runtime_put(&client->dev);
565 unlock_and_return:
566 mutex_unlock(&ov02a10->mutex);
567

Uninitialized scalar variable (UNINIT)
4. uninit_use: Using uninitialized value ret.

568 return ret;
569 }

Variable ret has not been initialized, so the error return value is a
garbage value. It should be initialized with some appropriate negative
error code, or ret could be removed and the return should return a
literal value of a error code.

I was unsure what value is appropriate to fix this, so instead I'm
reporting this issue.

Colin