X-Git-Url: http://git.bitcoin.ninja/index.cgi?a=blobdiff_plain;f=lightning%2Fsrc%2Fchain%2Fchannelmonitor.rs;h=a664c7c794efe019dd82e909c132c1fd839b9ccf;hb=refs%2Fheads%2F2023-02-no-recursive-read-locks;hp=8b281db6030dba2f681720a91eba819918d20d3f;hpb=a0c65c32a53077d548935835a8c2d211e91ce2cb;p=rust-lightning

diff --git a/lightning/src/chain/channelmonitor.rs b/lightning/src/chain/channelmonitor.rs
index 8b281db6..a664c7c7 100644
--- a/lightning/src/chain/channelmonitor.rs
+++ b/lightning/src/chain/channelmonitor.rs
@@ -60,7 +60,7 @@ use core::{cmp, mem};
 use crate::io::{self, Error};
 use core::convert::TryInto;
 use core::ops::Deref;
-use crate::sync::Mutex;
+use crate::sync::{Mutex, LockTestExt};
 
 /// An update generated by the underlying channel itself which contains some new information the
 /// [`ChannelMonitor`] should be made aware of.
@@ -851,9 +851,13 @@ pub type TransactionOutputs = (Txid, Vec<(u32, TxOut)>);
 
 impl<Signer: WriteableEcdsaChannelSigner> PartialEq for ChannelMonitor<Signer> where Signer: PartialEq {
 	fn eq(&self, other: &Self) -> bool {
-		let inner = self.inner.lock().unwrap();
-		let other = other.inner.lock().unwrap();
-		inner.eq(&other)
+		// We need some kind of total lockorder. Absent a better idea, we sort by position in
+		// memory and take locks in that order (assuming that we can't move within memory while a
+		// lock is held).
+		let ord = ((self as *const _) as usize) < ((other as *const _) as usize);
+		let a = if ord { self.inner.unsafe_well_ordered_double_lock_self() } else { other.inner.unsafe_well_ordered_double_lock_self() };
+		let b = if ord { other.inner.unsafe_well_ordered_double_lock_self() } else { self.inner.unsafe_well_ordered_double_lock_self() };
+		a.eq(&b)
 	}
 }
 
@@ -4066,7 +4070,10 @@ mod tests {
 	fn test_prune_preimages() {
 		let secp_ctx = Secp256k1::new();
 		let logger = Arc::new(TestLogger::new());
-		let broadcaster = Arc::new(TestBroadcaster{txn_broadcasted: Mutex::new(Vec::new()), blocks: Arc::new(Mutex::new(Vec::new()))});
+		let broadcaster = Arc::new(TestBroadcaster {
+			txn_broadcasted: Mutex::new(Vec::new()),
+			blocks: Arc::new(Mutex::new(Vec::new()))
+		});
 		let fee_estimator = TestFeeEstimator { sat_per_kw: Mutex::new(253) };
 
 		let dummy_key = PublicKey::from_secret_key(&secp_ctx, &SecretKey::from_slice(&[42; 32]).unwrap());