media: media/saa7164: fix saa7164_encoder_register() memory leak bugs

Add a fix for the memory leak bugs that can occur when the
saa7164_encoder_register() function fails.
The function allocates memory without explicitly freeing
it when errors occur.
Add a better error handling that deallocate the unused buffers before the
function exits during a fail.
Signed-off-by: Daniel Niv <danielniv3@gmail.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/pci/saa7164/saa7164-encoder.c

@@ -1008,7 +1008,7 @@ int saa7164_encoder_register(struct saa7164_port *port)
 		printk(KERN_ERR "%s() failed (errno = %d), NO PCI configuration\n",
 			__func__, result);
 		result = -ENOMEM;
-		goto failed;
+		goto fail_pci;
 	}
 
 	/* Establish encoder defaults here */
@@ -1062,7 +1062,7 @@ int saa7164_encoder_register(struct saa7164_port *port)
 			  100000, ENCODER_DEF_BITRATE);
 	if (hdl->error) {
 		result = hdl->error;
-		goto failed;
+		goto fail_hdl;
 	}
 
 	port->std = V4L2_STD_NTSC_M;
@@ -1080,7 +1080,7 @@ int saa7164_encoder_register(struct saa7164_port *port)
 		printk(KERN_INFO "%s: can't allocate mpeg device\n",
 			dev->name);
 		result = -ENOMEM;
-		goto failed;
+		goto fail_hdl;
 	}
 
 	port->v4l_device->ctrl_handler = hdl;
@@ -1091,10 +1091,7 @@ int saa7164_encoder_register(struct saa7164_port *port)
 	if (result < 0) {
 		printk(KERN_INFO "%s: can't register mpeg device\n",
 			dev->name);
-		/* TODO: We're going to leak here if we don't dealloc
-		 The buffers above. The unreg function can't deal wit it.
-		*/
-		goto failed;
+		goto fail_reg;
 	}
 
 	printk(KERN_INFO "%s: registered device video%d [mpeg]\n",
@@ -1116,9 +1113,14 @@ int saa7164_encoder_register(struct saa7164_port *port)
 
 	saa7164_api_set_encoder(port);
 	saa7164_api_get_encoder(port);
+	return 0;
 
-	result = 0;
-failed:
+fail_reg:
+	video_device_release(port->v4l_device);
+	port->v4l_device = NULL;
+fail_hdl:
+	v4l2_ctrl_handler_free(hdl);
+fail_pci:
 	return result;
 }