Avoid removing stale preimages when hashes collide in fuzzing

diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index a664c7c794efe019dd82e909c132c1fd839b9ccf..9e3afec6f53b8e67c4b76edcce2c491addb82af9 100644 (file)
--- a/lightning/src/chain/channelmonitor.rs
+++ b/lightning/src/chain/channelmonitor.rs
@@ -2041,8 +2041,12 @@ impl<Signer: WriteableEcdsaChannelSigner> ChannelMonitorImpl<Signer> {
                // Prune HTLCs from the previous counterparty commitment tx so we don't generate failure/fulfill
                // events for now-revoked/fulfilled HTLCs.
                if let Some(txid) = self.prev_counterparty_commitment_txid.take() {
-                       for &mut (_, ref mut source) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
-                               *source = None;
+                       if self.current_counterparty_commitment_txid.unwrap() != txid {
+                               for &mut (_, ref mut source_opt) in self.counterparty_claimable_outpoints.get_mut(&txid).unwrap() {
+                                       *source_opt = None;
+                               }
+                       } else {
+                               assert!(cfg!(fuzzing), "Commitment txids are unique outside of fuzzing, where hashes can collide");
                        }
                }
 
@@ -4168,10 +4172,10 @@ mod tests {
 
                monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..10])).unwrap();
                let dummy_txid = dummy_tx.txid();
-               monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
-               monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
-               monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
-               monitor.provide_latest_counterparty_commitment_tx(dummy_txid, preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
+               monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"1").into_inner()),
+                       preimages_slice_to_htlc_outputs!(preimages[5..15]), 281474976710655, dummy_key, &logger);
+               monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"2").into_inner()),
+                       preimages_slice_to_htlc_outputs!(preimages[15..20]), 281474976710654, dummy_key, &logger);
                for &(ref preimage, ref hash) in preimages.iter() {
                        let bounded_fee_estimator = LowerBoundedFeeEstimator::new(&fee_estimator);
                        monitor.provide_payment_preimage(hash, preimage, &broadcaster, &bounded_fee_estimator, &logger);
@@ -4185,6 +4189,9 @@ mod tests {
                test_preimages_exist!(&preimages[0..10], monitor);
                test_preimages_exist!(&preimages[15..20], monitor);
 
+               monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"3").into_inner()),
+                       preimages_slice_to_htlc_outputs!(preimages[17..20]), 281474976710653, dummy_key, &logger);
+
                // Now provide a further secret, pruning preimages 15-17
                secret[0..32].clone_from_slice(&hex::decode("c7518c8ae4660ed02894df8976fa1a3659c1a8b4b5bec0c4b872abeba4cb8964").unwrap());
                monitor.provide_secret(281474976710654, secret.clone()).unwrap();
@@ -4192,6 +4199,9 @@ mod tests {
                test_preimages_exist!(&preimages[0..10], monitor);
                test_preimages_exist!(&preimages[17..20], monitor);
 
+               monitor.provide_latest_counterparty_commitment_tx(Txid::from_inner(Sha256::hash(b"4").into_inner()),
+                       preimages_slice_to_htlc_outputs!(preimages[18..20]), 281474976710652, dummy_key, &logger);
+
                // Now update holder commitment tx info, pruning only element 18 as we still care about the
                // previous commitment tx's preimages too
                monitor.provide_latest_holder_commitment_tx(HolderCommitmentTransaction::dummy(), preimages_to_holder_htlcs!(preimages[0..5])).unwrap();