Commit ca9dc8d0 authored by Oliver Neukum's avatar Oliver Neukum Committed by Mauro Carvalho Chehab
Browse files

media: airspy: respect the DMA coherency rules 



If we want to avoid memory corruption
on incoherent architectures, buffers for DMA
must not reside
- on the stack
- embedded within other structures

Allocate them separately.

v2: fix uninitialized return value

Signed-off-by: default avatarOliver Neukum <oneukum@suse.com>
Signed-off-by: default avatarHans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: default avatarMauro Carvalho Chehab <mchehab@kernel.org>
parent 6a0d6733

drivers/media/usb/airspy/airspy.c

+15 −2
Original line number Diff line number Diff line
@@ -123,7 +123,7 @@ struct airspy { 


	/* USB control message buffer */

	#define BUF_SIZE 128

	u8 buf[BUF_SIZE];

	u8 *buf;



	/* Current configuration */

	unsigned int f_adc;
@@ -856,6 +856,7 @@ static void airspy_video_release(struct v4l2_device *v) 


	v4l2_ctrl_handler_free(&s->hdl);

	v4l2_device_unregister(&s->v4l2_dev);

	kfree(s->buf);

	kfree(s);

}
@@ -963,7 +964,10 @@ static int airspy_probe(struct usb_interface *intf, 
{

	struct airspy *s;

	int ret;

	u8 u8tmp, buf[BUF_SIZE];

	u8 u8tmp, *buf;



	buf = NULL;

	ret = -ENOMEM;



	s = kzalloc(sizeof(struct airspy), GFP_KERNEL);

	if (s == NULL) {
@@ -971,6 +975,13 @@ static int airspy_probe(struct usb_interface *intf, 
		return -ENOMEM;

	}



	s->buf = kzalloc(BUF_SIZE, GFP_KERNEL);

	if (!s->buf)

		goto err_free_mem;

	buf = kzalloc(BUF_SIZE, GFP_KERNEL);

	if (!buf)

		goto err_free_mem;



	mutex_init(&s->v4l2_lock);

	mutex_init(&s->vb_queue_lock);

	spin_lock_init(&s->queued_bufs_lock);
@@ -1068,6 +1079,8 @@ static int airspy_probe(struct usb_interface *intf, 
	v4l2_ctrl_handler_free(&s->hdl);

	v4l2_device_unregister(&s->v4l2_dev);

err_free_mem:

	kfree(buf);

	kfree(s->buf);

	kfree(s);

	return ret;

}