struct sysret sys_monitor_nullify_cap(capaddr_t cptr, uint8_t bits)
{
struct capability *root = &dcb_current->cspace.cap;
struct cte *cte;
errval_t err = caps_lookup_slot(root, cptr, bits, &cte,
CAPRIGHTS_READ_WRITE);
if (err_is_fail(err)) {
return SYSRET(err);
}
// remove from MDB
remove_mapping(cte);
// zero-out cap entry
assert(!mdb_reachable(cte));
memset(cte, 0, sizeof(*cte));
return SYSRET(SYS_ERR_OK);
}
/**
* \brief Cleanup a cap copy but not the object represented by the cap
*/
static errval_t
cleanup_copy(struct cte *cte)
{
errval_t err;
TRACE_CAP_MSG("cleaning up copy", cte);
struct capability *cap = &cte->cap;
if (type_is_vnode(cap->type) ||
cap->type == ObjType_Frame ||
cap->type == ObjType_DevFrame)
{
unmap_capability(cte);
}
if (distcap_is_foreign(cte)) {
TRACE_CAP_MSG("cleaning up non-owned copy", cte);
if (cte->mdbnode.remote_copies || cte->mdbnode.remote_descs) {
struct cte *ancestor = mdb_find_ancestor(cte);
if (ancestor) {
mdb_set_relations(ancestor, RRELS_DESC_BIT, RRELS_DESC_BIT);
}
}
}
err = mdb_remove(cte);
if (err_is_fail(err)) {
return err;
}
TRACE_CAP_MSG("cleaned up copy", cte);
assert(!mdb_reachable(cte));
memset(cte, 0, sizeof(*cte));
return SYS_ERR_OK;
}
