diff --git a/kernel/system/do_umap.c b/kernel/system/do_umap.c
index a19f191d0..eb83db7d9 100644
--- a/kernel/system/do_umap.c
+++ b/kernel/system/do_umap.c
@@ -53,8 +53,8 @@ PUBLIC int do_umap(struct proc * caller, message * m_ptr)
 	int new_proc_nr;
 	cp_grant_id_t grant = (cp_grant_id_t) offset;
 
-        if(verify_grant(targetpr->p_endpoint, ANY, grant, count, 0, 0,
-                &newoffset, &newep) != OK) {
+        if(verify_grant(targetpr->p_endpoint, caller->p_endpoint, grant, count,
+                0, 0, &newoffset, &newep) != OK) {
                 printf("SYSTEM: do_umap: verify_grant in %s, grant %d, bytes 0x%lx, failed, caller %s\n", targetpr->p_name, offset, count, caller->p_name);
 		proc_stacktrace(caller);
                 return EFAULT;