diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
index f59e3ea..9e079f1 100644
--- a/lib/efi_loader/efi_memory.c
+++ b/lib/efi_loader/efi_memory.c
@@ -407,11 +407,11 @@ efi_status_t efi_get_memory_map(unsigned long *memory_map_size,
 
 	map_size = map_entries * sizeof(struct efi_mem_desc);
 
+	*memory_map_size = map_size;
+
 	if (provided_map_size < map_size)
 		return EFI_BUFFER_TOO_SMALL;
 
-	*memory_map_size = map_size;
-
 	if (descriptor_size)
 		*descriptor_size = sizeof(struct efi_mem_desc);