Immediately archive ChannelMonitors for inbound unfuned channels - #4081

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wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
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Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
@TheBlueMatt

TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Add copy buttons to all
 blocks\n(function() {\n function addCopyButtons() {\n document.querySelectorAll('pre code').forEach(function(codeBlock) {\n if (codeBlock.parentElement.hasAttribute('data-copy-added')) return;\n codeBlock.parentElement.setAttribute('data-copy-added', 'true');\n \n var btn = document.createElement('button');\n btn.textContent = 'Copy';\n btn.style.cssText = 'position:absolute;top:4px;right:4px;padding:2px 8px;font-size:11px;background:#4ecdc4;border:none;border-radius:4px;color:#1a1a2e;cursor:pointer;opacity:0.7;transition:opacity 0.2s;';\n btn.onmouseover = function() { this.style.opacity = '1'; };\n btn.onmouseout = function() { this.style.opacity = '0.7'; };\n btn.onclick = function() {\n navigator.clipboard.writeText(codeBlock.textContent).then(function() {\n btn.textContent = 'Copied!';\n setTimeout(function() { btn.textContent = 'Copy'; }, 1500);\n });\n };\n codeBlock.parentElement.style.position = 'relative';\n codeBlock.parentElement.appendChild(btn);\n });\n }\n \n addCopyButtons();\n \n // Re-run on dynamic content\n var observer = new MutationObserver(addCopyButtons);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Add Copy Buttons to Code Blocks");
}
} catch(__e) { console.warn('[Userscript:Add Copy Buttons to Code Blocks]', __e); }
})();
(function(){
try {
var __m = "github.com";
var __re = new RegExp('^' + "github\\.com" + '
Skip to content

Immediately archive ChannelMonitors for inbound unfuned channels - #4081

Merged
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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@TheBlueMatt

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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👋 I see @tankyleo was un-assigned.
If you'd like another reviewer assignment, please click here.

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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

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📢 Have feedback on the report? Share it here.

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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
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TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Force GitHub README to respect dark mode\n(function() {\n var style = document.createElement('style');\n style.textContent = '\n .markdown-body {\n color-scheme: dark light;\n }\n .markdown-body pre { background: #161b22 !important; }\n .markdown-body code { background: rgba(110, 118, 129, 0.4) !important; }\n .markdown-body table th, .markdown-body table td { border-color: #30363d !important; }\n .markdown-body img { background: #0d1117; }\n .markdown-body blockquote { border-left-color: #8b949e; }\n .markdown-body hr { border-color: #30363d; }\n ';\n document.head.appendChild(style);\n})();", "GitHub Dark Mode README Fix"); } } catch(__e) { console.warn('[Userscript:GitHub Dark Mode README Fix]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Immediately archive ChannelMonitors for inbound unfuned channels - #4081

Merged
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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@TheBlueMatt

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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👋 I see @tankyleo was un-assigned.
If you'd like another reviewer assignment, please click here.

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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

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📢 Have feedback on the report? Share it here.

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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Highlight search terms from Google/DuckDuckGo/Bing referrer\n(function() {\n var ref = document.referrer;\n var terms = [];\n \n if (ref.includes('google.com') || ref.includes('duckduckgo.com') || ref.includes('bing.com')) {\n var url = new URL(ref);\n var q = url.searchParams.get('q') || url.searchParams.get('p');\n if (q) {\n terms = q.split(/\\s+/).filter(function(t) { return t.length > 2; });\n }\n }\n \n if (terms.length === 0) return;\n \n var style = document.createElement('style');\n style.textContent = '.userscript-highlight { background: #fbbf24; color: #1a1a2e; padding: 1px 3px; border-radius: 2px; }';\n document.head.appendChild(style);\n \n function highlight(node) {\n if (node.nodeType === 3) { // text node\n var text = node.textContent;\n var found = false;\n terms.forEach(function(term) {\n var regex = new RegExp('(' + term.replace(/[.*+?^${}()|[\\]\\\\]/g, '\\\\') + ')', 'gi');\n if (regex.test(text)) {\n found = true;\n var frag = document.createDocumentFragment();\n var parts = text.split(regex);\n parts.forEach(function(part, i) {\n if (i % 2 === 0) {\n frag.appendChild(document.createTextNode(part));\n } else {\n var span = document.createElement('span');\n span.className = 'userscript-highlight';\n span.textContent = part;\n frag.appendChild(span);\n }\n });\n node.parentNode.replaceChild(frag, node);\n }\n });\n } else if (node.nodeType === 1 && node.childNodes) { // element\n var skipTags = ['SCRIPT', 'STYLE', 'NOSCRIPT', 'TEXTAREA', 'INPUT', 'SELECT'];\n if (!skipTags.includes(node.tagName)) {\n Array.from(node.childNodes).forEach(highlight);\n }\n }\n }\n \n highlight(document.body);\n \n // Re-highlight on dynamic content\n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1 || node.nodeType === 3) highlight(node);\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Highlight Search Terms"); } } catch(__e) { console.warn('[Userscript:Highlight Search Terms]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
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Immediately archive ChannelMonitors for inbound unfuned channels - #4081

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lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
@TheBlueMatt

TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Strip utm_, fbclid, gclid, etc. from all links on page\n(function() {\n var trackingParams = ['utm_source', 'utm_medium', 'utm_campaign', 'utm_term', 'utm_content',\n 'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',\n 'ref', 'ref_src', 'source', 'medium', 'campaign'];\n \n function cleanUrl(url) {\n try {\n var u = new URL(url, window.location.origin);\n var changed = false;\n trackingParams.forEach(function(p) {\n if (u.searchParams.has(p)) {\n u.searchParams.delete(p);\n changed = true;\n }\n });\n return changed ? u.toString() : url;\n } catch (e) {\n return url;\n }\n }\n \n function cleanLinks() {\n document.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n \n cleanLinks();\n \n var observer = new MutationObserver(function(mutations) {\n mutations.forEach(function(m) {\n m.addedNodes.forEach(function(node) {\n if (node.nodeType === 1) {\n if (node.tagName === 'A') cleanLinks();\n node.querySelectorAll('a[href]').forEach(function(a) {\n var clean = cleanUrl(a.href);\n if (clean !== a.href) a.href = clean;\n });\n }\n });\n });\n });\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "Remove Tracking Parameters from Links"); } } catch(__e) { console.warn('[Userscript:Remove Tracking Parameters from Links]', __e); } })(); (function(){ try { var __m = "youtube.com"; var __re = new RegExp('^' + "youtube\\.com" + '
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Immediately archive ChannelMonitors for inbound unfuned channels - #4081

Merged
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

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  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
@TheBlueMatt

TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

4 participants

@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Auto-enable theater mode on YouTube\n(function() {\n function tryTheater() {\n var btn = document.querySelector('button[aria-label=\"Theater mode\"], ytd-player #player button[title=\"Theater mode\"]');\n if (btn && !btn.classList.contains('activated')) {\n btn.click();\n }\n }\n \n // Try immediately\n tryTheater();\n \n // Try after navigation (SPA)\n var lastUrl = location.href;\n setInterval(function() {\n if (location.href !== lastUrl) {\n lastUrl = location.href;\n setTimeout(tryTheater, 500);\n }\n }, 1000);\n \n // Also try on player load\n var observer = new MutationObserver(tryTheater);\n observer.observe(document.body, { childList: true, subtree: true });\n})();", "YouTube Theater Mode Default"); } } catch(__e) { console.warn('[Userscript:YouTube Theater Mode Default]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

Immediately archive ChannelMonitors for inbound unfuned channels - #4081

Merged
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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@TheBlueMatt

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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👋 I see @tankyleo was un-assigned.
If you'd like another reviewer assignment, please click here.

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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

🚀 New features to boost your workflow:
  • ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.

Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Remove or un-stick sticky/fixed headers that block content\n(function() {\n function unstick() {\n document.querySelectorAll('header, nav, [role=\"banner\"], .header, .navbar, .sticky, .fixed-top, [style*=\"position: fixed\"], [style*=\"position:sticky\"]').forEach(function(el) {\n if (el.style.position === 'fixed' || el.style.position === 'sticky' || \n getComputedStyle(el).position === 'fixed' || getComputedStyle(el).position === 'sticky') {\n el.style.position = 'static';\n el.style.top = 'auto';\n el.style.zIndex = 'auto';\n }\n });\n }\n \n unstick();\n \n var observer = new MutationObserver(unstick);\n observer.observe(document.body, { childList: true, subtree: true, attributes: true, attributeFilter: ['style', 'class'] });\n})();", "Kill Sticky Headers"); } } catch(__e) { console.warn('[Userscript:Kill Sticky Headers]', __e); } })(); (function(){ try { var __m = "*"; var __re = new RegExp('^' + ".*" + '
Skip to content

Immediately archive ChannelMonitors for inbound unfuned channels - #4081

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wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
@TheBlueMatt

TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino
, 'i'); if (__m === '*' || __re.test(location.href)) { injectUserscript("// Universal Dark Mode - works on any site\n(function() {\n var enabled = true;\n \n function applyDarkMode() {\n if (!enabled) return;\n \n // Create style element if it doesn't exist\n var style = document.getElementById('universal-dark-mode-style');\n if (!style) {\n style = document.createElement('style');\n style.id = 'universal-dark-mode-style';\n document.head.appendChild(style);\n }\n \n // Dark mode CSS - inverts colors but preserves images/video\n style.textContent = '\n /* Invert everything except media */\n html {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #1a1a2e !important;\n }\n \n /* Restore images, videos, iframes, canvas */\n img, video, iframe, canvas, svg, picture, [style*=\"background-image\"] {\n filter: invert(1) hue-rotate(180deg) !important;\n }\n \n /* Preserve specific elements that should not be inverted */\n .no-dark-mode, .no-dark-mode *,\n [data-theme=\"light\"], [data-theme=\"light\"],\n .ace_editor, .ace_editor *,\n .CodeMirror, .CodeMirror *,\n .monaco-editor, .monaco-editor *,\n .markdown-body pre, .markdown-body pre *,\n .highlight, .highlight *,\n pre code, pre code * {\n filter: none !important;\n }\n \n /* Fix common UI elements */\n .modal, .popup, .dropdown-menu, .tooltip, .popover {\n filter: invert(1) hue-rotate(180deg) !important;\n background: #2d2d44 !important;\n border-color: #444 !important;\n }\n \n /* Scrollbars */\n ::-webkit-scrollbar { background: #1a1a2e !important; }\n ::-webkit-scrollbar-thumb { background: #444 !important; }\n ::-webkit-scrollbar-thumb:hover { background: #555 !important; }\n \n /* Selection */\n ::selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ::-moz-selection { background: #4ecdc4 !important; color: #1a1a2e !important; }\n ';\n }\n \n function removeDarkMode() {\n var style = document.getElementById('universal-dark-mode-style');\n if (style) style.remove();\n }\n \n // Toggle with Alt+Shift+D\n document.addEventListener('keydown', function(e) {\n if (e.altKey && e.shiftKey && e.key === 'D') {\n e.preventDefault();\n enabled = !enabled;\n if (enabled) {\n applyDarkMode();\n console.log('[Universal Dark Mode] Enabled');\n } else {\n removeDarkMode();\n console.log('[Universal Dark Mode] Disabled');\n }\n }\n });\n \n // Apply on load\n applyDarkMode();\n \n // Re-apply on dynamic content\n var observer = new MutationObserver(function(mutations) {\n if (enabled && !document.getElementById('universal-dark-mode-style')) {\n applyDarkMode();\n }\n });\n observer.observe(document.head, { childList: true });\n \n console.log('[Universal Dark Mode] Loaded - Press Alt+Shift+D to toggle');\n})();", "Universal Dark Mode"); } } catch(__e) { console.warn('[Userscript:Universal Dark Mode]', __e); } })(); })();
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Immediately archive ChannelMonitors for inbound unfuned channels - #4081

Merged
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors
Sep 18, 2025
Merged

Immediately archive ChannelMonitors for inbound unfuned channels#4081
wpaulino merged 1 commit into
lightningdevkit:mainfrom
TheBlueMatt:2025-09-drop-inb-unfunded-monitors

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If a peer opens a channel to us, but never actually broadcasts the funding transaction, we'll still keep a ChannelMonitor around for the channel. While we maybe shouldn't do this either, when the channel ultimately times out 2016 blocks later, we should at least immediately archive the ChannelMonitor, which we do here.

Fixes#3384

@TheBlueMattTheBlueMatt added this to the 0.2 milestone Sep 18, 2025
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If you'd like another reviewer assignment, please click here.

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Tagged this "backport 0.1" cause it seems like an important bugfix, but I'm open to feedback from reviewers on that.

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Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 88.60%. Comparing base (5ae19b4) to head (744664e).
⚠️ Report is 53 commits behind head on main.

Additional details and impacted files
@@ Coverage Diff @@## main #4081 +/- ##
==========================================
+ Coverage 88.33% 88.60% +0.26% 
==========================================
Files 177 176 -1 Lines 131896 132097 +201 Branches 131896 132097 +201 ==========================================
+ Hits 116512 117045 +533 + Misses 12728 12387 -341 - Partials 2656 2665 +9 
FlagCoverage Δ
fuzzing21.93% <25.80%> (+0.32%)⬆️
tests88.44% <100.00%> (+0.26%)⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.

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Comment threadlightning/src/chain/channelmonitor.rs Outdated
Comment threadlightning/src/ln/functional_tests.rs
@TheBlueMatt
TheBlueMattforce-pushed the 2025-09-drop-inb-unfunded-monitors branch 2 times, most recently from d0018e3 to f7d3296CompareSeptember 18, 2025 16:16
@TheBlueMatt

TheBlueMatt commented Sep 18, 2025

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$ git diff-tree -U3 278aaa1fc 744664e88
diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 0237e653db..c17cd87d49 100644
--- a/lightning/src/chain/channelmonitor.rs+++ b/lightning/src/chain/channelmonitor.rs@@ -2571,12 +2571,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
let current_height = self.current_best_block().height;
let mut inner = self.inner.lock().unwrap();
- let mut commitment_not_advanced =- inner.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- inner.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (inner.holder_tx_signed || inner.lockdown_from_offchain)- && commitment_not_advanced+ if inner.is_closed_without_updates()
&& is_all_funds_claimed
&& !inner.funding_spend_seen
{
@@ -3079,12 +3074,7 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitor<Signer> {
// Avoiding including a `Balance` if none of these are true allows us to prune monitors
// for chanels that were opened inbound to us but where the funding transaction never
// confirmed at all.
- let mut commitment_not_advanced =- us.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;- commitment_not_advanced &=- us.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;- if (!us.holder_tx_signed && !us.lockdown_from_offchain)- || !commitment_not_advanced+ if !us.is_closed_without_updates()
|| balance_candidates.iter().any(|bal| bal.amount_satoshis != 0)
{
res.push(Balance::ClaimableOnChannelClose {
@@ -4383,6 +4373,16 @@ impl<Signer: EcdsaChannelSigner> ChannelMonitorImpl<Signer> {
} else { ret }
}
+	/// Returns true if the channel has been closed (i.e. no further updates are allowed) and no+	/// commitment state updates ever happened.+	fn is_closed_without_updates(&self) -> bool {+ let mut commitment_not_advanced =+ self.current_counterparty_commitment_number == INITIAL_COMMITMENT_NUMBER;+ commitment_not_advanced &=+ self.current_holder_commitment_number == INITIAL_COMMITMENT_NUMBER;+ (self.holder_tx_signed || self.lockdown_from_offchain) && commitment_not_advanced+	}+
fn no_further_updates_allowed(&self) -> bool {
self.funding_spend_seen || self.lockdown_from_offchain || self.holder_tx_signed
}
diff --git a/lightning/src/ln/functional_tests.rs b/lightning/src/ln/functional_tests.rs
index 46ff741a54..bc089d495b 100644
--- a/lightning/src/ln/functional_tests.rs+++ b/lightning/src/ln/functional_tests.rs@@ -6635,6 +6635,10 @@ pub fn test_channel_conf_timeout() {
let funding_tx =
create_chan_between_nodes_with_value_init(&nodes[0], &nodes[1], 1_000_000, 100_000);
+	// Inbound channels which haven't advanced state at all and never were funded will generate+	// claimable `Balance`s until they're closed.+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// The outbound node should wait forever for confirmation:
// This matches `channel::FUNDING_CONF_DEADLINE_BLOCKS` and BOLT 2's suggested timeout, thus is
// copied here instead of directly referencing the constant.
@@ -6648,6 +6652,7 @@ pub fn test_channel_conf_timeout() {
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 1);
+	assert!(!nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
connect_blocks(&nodes[1], 1);
check_added_monitors(&nodes[1], 1);
@@ -6668,9 +6673,14 @@ pub fn test_channel_conf_timeout() {
_ => panic!("Unexpected event"),
}
+	// Once an inbound never-confirmed channel is closed, it will no longer generate any claimable+	// `Balance`s.+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());+
// Once the funding times out the monitor should be immediately archived.
nodes[1].chain_monitor.chain_monitor.archive_fully_resolved_channel_monitors();
assert_eq!(nodes[1].chain_monitor.chain_monitor.list_monitors().len(), 0);
+	assert!(nodes[1].chain_monitor.chain_monitor.get_claimable_balances(&[]).is_empty());
// Remove the corresponding outputs and transactions the chain source is
// watching. This is to make sure the `Drop` function assertions pass.

tnull
tnull previously approved these changes Sep 18, 2025
If a peer opens a channel to us, but never actually broadcasts the
funding transaction, we'll still keep a `ChannelMonitor` around for
the channel. While we maybe shouldn't do this either, when the
channel ultimately times out 2016 blocks later, we should at least
immediately archive the `ChannelMonitor`, which we do here.
Fixeslightningdevkit#3384
@TheBlueMatt

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Oops sorry test was wrong.

@wpaulino
wpaulino merged commit 981e95f into lightningdevkit:mainSep 18, 2025
24 of 25 checks passed
@tankyleo
tankyleo removed their request for review September 18, 2025 23:52
@TheBlueMattTheBlueMatt mentioned this pull request Oct 6, 2025
@TheBlueMatt

TheBlueMatt commented Oct 6, 2025

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Backported in #4143

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Drop ChannelMonitors for inbound, no-local-funding channels after they time out

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@TheBlueMatt@ldk-reviews-bot@tnull@wpaulino