f - ensure splice contribution is non-zero

Author: jkczyz

lightning/src/ln/channel.rs

@@ -10676,6 +10676,15 @@ where
 		// TODO(splicing): check for quiescence
 
 		let our_funding_contribution = contribution.value();
+		if our_funding_contribution == SignedAmount::ZERO {
+			return Err(APIError::APIMisuseError {
+				err: format!(
+					"Channel {} cannot be spliced; contribution cannot be zero",
+					self.context.channel_id(),
+				),
+			});
+		}
+
 		if our_funding_contribution > SignedAmount::MAX_MONEY {
 			return Err(APIError::APIMisuseError {
 				err: format!(