In the Linux kernel, the following vulnerability has been resolved:

pcmcia: Fix a NULL pointer dereference in __iodyn_find_io_region()

In __iodyn_find_io_region(), pcmcia_make_resource() is assigned to
res and used in pci_bus_alloc_resource(). There is a dereference of res
in pci_bus_alloc_resource(), which could lead to a NULL pointer
dereference on failure of pcmcia_make_resource().

Fix this bug by adding a check of res.