Almost all r128's private ioctls require that the CCE state has
already been initialised. However, most do not test that this has
been done, and will proceed to dereference a null pointer. This may
result in a security vulnerability, since some ioctls are
unprivileged.
This adds a macro for the common initialisation test and changes all
ioctl implementations that require prior initialisation to use that
macro.
Also, r128_do_init_cce() does not test that the CCE state has not
been initialised already. Repeated initialisation may lead to a crash
or resource leak. This adds that test.
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Dave Airlie <airlied@redhat.com>
7dc482dfee