From ecba340c9de7202d04e338b427ae9cffe628aa08 Mon Sep 17 00:00:00 2001
From: Emilia Hane <elsaemiliaevahane@gmail.com>
Date: Wed, 28 Feb 2024 14:14:15 +0100
Subject: [PATCH] Ensure consistency between aborted set and reused ptrs
 (#6844)

---
 crates/storage/libmdbx-rs/src/error.rs       |  4 +--
 crates/storage/libmdbx-rs/src/txn_manager.rs | 34 ++++++++++++++++++++
 2 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/crates/storage/libmdbx-rs/src/error.rs b/crates/storage/libmdbx-rs/src/error.rs
index aff584619..22e440426 100644
--- a/crates/storage/libmdbx-rs/src/error.rs
+++ b/crates/storage/libmdbx-rs/src/error.rs
@@ -224,8 +224,8 @@ pub(crate) fn mdbx_result_with_tx_kind<K: TransactionKind>(
     txn_manager: &TxnManager,
 ) -> Result<bool> {
     if K::IS_READ_ONLY &&
-        err_code == ffi::MDBX_EBADSIGN &&
-        txn_manager.remove_aborted_read_transaction(txn).is_some()
+        txn_manager.remove_aborted_read_transaction(txn).is_some() &&
+        err_code == ffi::MDBX_EBADSIGN
     {
         return Err(Error::ReadTransactionAborted)
     }
diff --git a/crates/storage/libmdbx-rs/src/txn_manager.rs b/crates/storage/libmdbx-rs/src/txn_manager.rs
index 99328457c..bf46680b8 100644
--- a/crates/storage/libmdbx-rs/src/txn_manager.rs
+++ b/crates/storage/libmdbx-rs/src/txn_manager.rs
@@ -418,5 +418,39 @@ mod read_transactions {
 
             assert!(read_transactions.active.contains_key(&(txn_ptr.0 as usize)));
         }
+
+        #[test]
+        fn txn_manager_reassign_transaction_removes_from_aborted_transactions() {
+            const MAX_DURATION: Duration = Duration::from_secs(1);
+
+            let dir = tempdir().unwrap();
+            let env = Environment::builder()
+                .set_max_read_transaction_duration(MaxReadTransactionDuration::Set(MAX_DURATION))
+                .open(dir.path())
+                .unwrap();
+
+            let read_transactions = env.txn_manager().read_transactions.as_ref().unwrap();
+
+            // Create a read-only transaction, wait until `MAX_DURATION` time is elapsed so the
+            // manager kills it, use it and observe the `Error::ReadTransactionAborted` error.
+            {
+                let tx = env.begin_ro_txn().unwrap();
+                let tx_ptr = tx.txn() as usize;
+                assert!(read_transactions.active.contains_key(&tx_ptr));
+
+                sleep(MAX_DURATION + READ_TRANSACTIONS_CHECK_INTERVAL);
+
+                assert!(!read_transactions.active.contains_key(&tx_ptr));
+                assert!(read_transactions.aborted.contains(&tx_ptr));
+            }
+
+            // Create a read-only transaction, ensure this removes it from aborted set if mdbx
+            // reassigns same recently aborted transaction pointer.
+            {
+                let tx = env.begin_ro_txn().unwrap();
+                let tx_ptr = tx.txn() as usize;
+                assert!(!read_transactions.aborted.contains(&tx_ptr));
+            }
+        }
     }
 }