f don't run tx_signatures checks upon receiving duplicate tx_signatures

Author: dunxen

lightning/src/ln/channel.rs

@@ -6591,7 +6591,10 @@ impl<SP: Deref> FundedChannel<SP> where
 	pub fn tx_signatures<L: Deref>(&mut self, msg: &msgs::TxSignatures, logger: &L) -> Result<(Option<Transaction>, Option<msgs::TxSignatures>), ChannelError>
 		where L::Target: Logger
 	{
-		if !matches!(self.context.channel_state, ChannelState::FundingNegotiated(flags) if flags.is_interactive_signing()) {
+		if !matches!(
+			self.context.channel_state,
+			ChannelState::FundingNegotiated(flags) if flags.is_interactive_signing() || !flags.is_their_tx_signatures_sent()
+		) {
 			return Err(ChannelError::Ignore("Ignoring tx_signatures received outside of interactive signing".to_owned()));
 		}