In the Linux kernel, the following vulnerability has been resolved:
dpaa2-switch: put MAC endpoint device on disconnect
fsl_mc_get_endpoint() returns the MAC endpoint device with a reference
taken through device_find_child(). The switch port connect path stores
that device in mac->mc_dev and keeps it for the lifetime of the connected
MAC object.
However, the disconnect path only closes the MAC and frees the dpaa2_mac
object. It does not drop the endpoint device reference stored in
mac->mc_dev, so every successful connect leaks that device reference when
the MAC is later disconnected.
Drop the endpoint device reference before freeing the dpaa2_mac object.