diff --git a/src/boot/efi/cpio.c b/src/boot/efi/cpio.c
index c71c218e4f..a800959c88 100644
--- a/src/boot/efi/cpio.c
+++ b/src/boot/efi/cpio.c
@@ -504,7 +504,7 @@ EFI_STATUS pack_cpio_literal(
 
         uint32_t inode = 1; /* inode counter, so that each item gets a new inode */
         _cleanup_free_ void *buffer = NULL;
-        UINTN buffer_size;
+        UINTN buffer_size = 0;
         EFI_STATUS err;
 
         assert(data || data_size == 0);