diff --git a/src/service/admin/mod.rs b/src/service/admin/mod.rs
index 681974b6..f496c414 100644
--- a/src/service/admin/mod.rs
+++ b/src/service/admin/mod.rs
@@ -178,9 +178,10 @@ impl Service {
 				.text_to_file(message_content.body())
 				.await
 				.expect("failed to create text file");
+			let size_u64: u64 = message_content.body().len().try_into().map_or(0, |n| n);
 			let metadata = FileInfo {
 				mimetype: Some("text/markdown".to_owned()),
-				size: Some(UInt::new_saturating(message_content.body().len() as u64)),
+				size: Some(UInt::new_saturating(size_u64)),
 				thumbnail_info: None,
 				thumbnail_source: None,
 			};