media: vidtv: move kfree(dvb) to vidtv_bridge_dev_release()

Adding kfree(dvb) to vidtv_bridge_remove() will remove the memory
too soon: if an application still has an open filehandle to the device
when the driver is unloaded, then when that filehandle is closed, a
use-after-free access takes place to the freed memory.

Move the kfree(dvb) to vidtv_bridge_dev_release() instead.

Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Fixes: 76e21bb8be ("media: vidtv: Fix memory leak in remove")
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
This commit is contained in:
Hans Verkuil 2021-09-14 08:21:25 +01:00 committed by Mauro Carvalho Chehab
parent fe47b6d758
commit 112024a3b6

View File

@ -557,7 +557,6 @@ static int vidtv_bridge_remove(struct platform_device *pdev)
dvb_dmxdev_release(&dvb->dmx_dev);
dvb_dmx_release(&dvb->demux);
dvb_unregister_adapter(&dvb->adapter);
kfree(dvb);
dev_info(&pdev->dev, "Successfully removed vidtv\n");
return 0;
@ -565,6 +564,10 @@ static int vidtv_bridge_remove(struct platform_device *pdev)
static void vidtv_bridge_dev_release(struct device *dev)
{
struct vidtv_dvb *dvb;
dvb = dev_get_drvdata(dev);
kfree(dvb);
}
static struct platform_device vidtv_bridge_dev = {