Fix handling of duplicate initial `ChannelMonitor` writing

[rust-lightning] / lightning / src / ln / channelmanager.rs

diff --git a/lightning/src/ln/channelmanager.rs b/lightning/src/ln/channelmanager.rs
index 7fe99607528f1bef92007199dc4c04417161c167..81b9d766d7b39a3e91b633e62ea72b94e1eab5bb 100644 (file)
--- a/lightning/src/ln/channelmanager.rs
+++ b/lightning/src/ln/channelmanager.rs
@@ -6374,7 +6374,7 @@ where
                                        let res =
                                                chan.funding_signed(&msg, best_block, &self.signer_provider, &&logger);
                                        match res {
-                                               Ok((chan, monitor)) => {
+                                               Ok((mut chan, monitor)) => {
                                                        if let Ok(persist_status) = self.chain_monitor.watch_channel(chan.context.get_funding_txo().unwrap(), monitor) {
                                                                // We really should be able to insert here without doing a second
                                                                // lookup, but sadly rust stdlib doesn't currently allow keeping
@@ -6386,6 +6386,11 @@ where
                                                                Ok(())
                                                        } else {
                                                                let e = ChannelError::Close("Channel funding outpoint was a duplicate".to_owned());
+                                                               // We weren't able to watch the channel to begin with, so no
+                                                               // updates should be made on it. Previously, full_stack_target
+                                                               // found an (unreachable) panic when the monitor update contained
+                                                               // within `shutdown_finish` was applied.
+                                                               chan.unset_funding_info(msg.channel_id);
                                                                return Err(convert_chan_phase_err!(self, e, &mut ChannelPhase::Funded(chan), &msg.channel_id).1);
                                                        }
                                                },