Commit message: media: rc: prevent memory leak in cx23888_ir_probe

In cx23888_ir_probe if kfifo_alloc fails the allocated memory for state
should be released.

Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Sean Young <sean@mess.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
CVE: CVE-2019-19054
CWE: CWE-401
Vulnerability description: A memory leak in the cx23888_ir_probe() function in drivers/media/pci/cx23885/cx23888-ir.c in the Linux kernel through 5.3.11 allows attackers to cause a denial of service (memory consumption) by triggering kfifo_alloc() failures, aka CID-a7b2df76b42b.

Project: linux
File: cx23888-ir.c

int cx23888_ir_probe(struct cx23885_dev *dev)
{
	struct cx23888_ir_state *state;
	struct v4l2_subdev *sd;
	struct v4l2_subdev_ir_parameters default_params;
	int ret;

	state = kzalloc(sizeof(struct cx23888_ir_state), GFP_KERNEL);
	if (state == NULL)
		return -ENOMEM;

	spin_lock_init(&state->rx_kfifo_lock);
	if (kfifo_alloc(&state->rx_kfifo, CX23888_IR_RX_KFIFO_SIZE, GFP_KERNEL))
		return -ENOMEM;

	state->dev = dev;
	sd = &state->sd;

	v4l2_subdev_init(sd, &cx23888_ir_controller_ops);
	v4l2_set_subdevdata(sd, state);
	/* FIXME - fix the formatting of dev->v4l2_dev.name and use it */
	snprintf(sd->name, sizeof(sd->name), "%s/888-ir", dev->name);
	sd->grp_id = CX23885_HW_888_IR;

	ret = v4l2_device_register_subdev(&dev->v4l2_dev, sd);
	if (ret == 0) {
		/*
		 * Ensure no interrupts arrive from '888 specific conditions,
		 * since we ignore them in this driver to have commonality with
		 * similar IR controller cores.
		 */
		cx23888_ir_write4(dev, CX23888_IR_IRQEN_REG, 0);

		mutex_init(&state->rx_params_lock);
		default_params = default_rx_params;
		v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);

		mutex_init(&state->tx_params_lock);
		default_params = default_tx_params;
		v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
	} else {
		kfifo_free(&state->rx_kfifo);
	}
	return ret;
}

Project: linux
File: cx23888-ir.c

int cx23888_ir_probe(struct cx23885_dev *dev)
{
	struct cx23888_ir_state *state;
	struct v4l2_subdev *sd;
	struct v4l2_subdev_ir_parameters default_params;
	int ret;

	state = kzalloc(sizeof(struct cx23888_ir_state), GFP_KERNEL);
	if (state == NULL)
		return -ENOMEM;

	spin_lock_init(&state->rx_kfifo_lock);
	if (kfifo_alloc(&state->rx_kfifo, CX23888_IR_RX_KFIFO_SIZE,
			GFP_KERNEL)) {
		kfree(state);
		return -ENOMEM;
	}

	state->dev = dev;
	sd = &state->sd;

	v4l2_subdev_init(sd, &cx23888_ir_controller_ops);
	v4l2_set_subdevdata(sd, state);
	/* FIXME - fix the formatting of dev->v4l2_dev.name and use it */
	snprintf(sd->name, sizeof(sd->name), "%s/888-ir", dev->name);
	sd->grp_id = CX23885_HW_888_IR;

	ret = v4l2_device_register_subdev(&dev->v4l2_dev, sd);
	if (ret == 0) {
		/*
		 * Ensure no interrupts arrive from '888 specific conditions,
		 * since we ignore them in this driver to have commonality with
		 * similar IR controller cores.
		 */
		cx23888_ir_write4(dev, CX23888_IR_IRQEN_REG, 0);

		mutex_init(&state->rx_params_lock);
		default_params = default_rx_params;
		v4l2_subdev_call(sd, ir, rx_s_parameters, &default_params);

		mutex_init(&state->tx_params_lock);
		default_params = default_tx_params;
		v4l2_subdev_call(sd, ir, tx_s_parameters, &default_params);
	} else {
		kfifo_free(&state->rx_kfifo);
	}
	return ret;
}