media: dvb-core: fix a memory leak bug

In dvb_create_media_entity(), 'dvbdev->entity' is allocated through
kzalloc(). Then, 'dvbdev->pads' is allocated through kcalloc(). However, if
kcalloc() fails, the allocated 'dvbdev->entity' is not deallocated, leading
to a memory leak bug. To fix this issue, free 'dvbdev->entity' before
returning -ENOMEM.

Signed-off-by: Wenwen Wang <[e-mail]>
Signed-off-by: Sean Young <[e-mail]>
Signed-off-by: Mauro Carvalho Chehab <[e-mail]>

drivers/media/dvb-core/dvbdev.c

···
 	if (npads) {
 		dvbdev->pads = kcalloc(npads, sizeof(*dvbdev->pads),
 				       GFP_KERNEL);
-		if (!dvbdev->pads)
+		if (!dvbdev->pads) {
+			kfree(dvbdev->entity);
 			return -ENOMEM;
+		}
 	}
 
 	switch (type) {