s390/vfio-ap: fix memory leak in vfio_ap device driver

The device release callback function invoked to release the matrix device
uses the dev_get_drvdata(device *dev) function to retrieve the
pointer to the vfio_matrix_dev object in order to free its storage. The
problem is, this object is not stored as drvdata with the device; since the
kfree function will accept a NULL pointer, the memory for the
vfio_matrix_dev object is never freed.

Since the device being released is contained within the vfio_matrix_dev
object, the container_of macro will be used to retrieve its pointer.

Fixes: 1fde573413 ("s390: vfio-ap: base implementation of VFIO AP device driver")
Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
Reviewed-by: Harald Freudenberger <freude@linux.ibm.com>
Link: https://lore.kernel.org/r/20230320150447.34557-1-akrowiak@linux.ibm.com
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
This commit is contained in:
Tony Krowiak 2023-03-20 11:04:47 -04:00 committed by Vasily Gorbik
parent 89aba4c26f
commit 8f8cf76758

View File

@ -54,8 +54,9 @@ static struct ap_driver vfio_ap_drv = {
static void vfio_ap_matrix_dev_release(struct device *dev)
{
struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev);
struct ap_matrix_dev *matrix_dev;
matrix_dev = container_of(dev, struct ap_matrix_dev, device);
kfree(matrix_dev);
}