From 860f17971202432ee7060494a518db48df09bcb4 Mon Sep 17 00:00:00 2001
From: hvlad <hvlad@users.sourceforge.net>
Date: Sun, 17 Dec 2017 02:05:00 +0200
Subject: [PATCH] Fixed bug CORE-5681 : AV when external statement is executed
 and local transaction is rolled back

---
 src/jrd/extds/ExtDS.cpp | 31 +++++++++++++++++++++++++------
 src/jrd/extds/ExtDS.h   |  4 ++--
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/src/jrd/extds/ExtDS.cpp b/src/jrd/extds/ExtDS.cpp
index 2c3fcb58b4..81ed035e58 100644
--- a/src/jrd/extds/ExtDS.cpp
+++ b/src/jrd/extds/ExtDS.cpp
@@ -365,8 +365,24 @@ Transaction* Connection::createTransaction()
 	return tran;
 }
 
-void Connection::deleteTransaction(Transaction* tran)
+void Connection::deleteTransaction(thread_db* tdbb, Transaction* tran)
 {
+	// Close all active statements in tran context avoiding commit of already 
+	// deleted transaction
+	Statement** stmt_ptr = m_statements.begin();
+	while (stmt_ptr < m_statements.end())
+	{
+		Statement* stmt = *stmt_ptr;
+		if (stmt->getTransaction() == tran)
+		{
+			if (stmt->isActive())
+				stmt->close(tdbb, true);
+		}
+		// close() above could destroy statement and remove it from m_statements
+		if (stmt_ptr < m_statements.end() && *stmt_ptr == stmt)
+			stmt_ptr++;
+	}
+
 	FB_SIZE_T pos;
 	if (m_transactions.find(tran, pos))
 	{
@@ -378,7 +394,7 @@ void Connection::deleteTransaction(Transaction* tran)
 	}
 
 	if (!m_used_stmts && m_transactions.getCount() == 0 && !m_deleting)
-		m_provider.releaseConnection(JRD_get_thread_data(), *this);
+		m_provider.releaseConnection(tdbb, *this);
 }
 
 Statement* Connection::createStatement(const string& sql)
@@ -657,7 +673,7 @@ void Transaction::commit(thread_db* tdbb, bool retain)
 	if (!retain)
 	{
 		detachFromJrdTran();
-		m_connection.deleteTransaction(this);
+		m_connection.deleteTransaction(tdbb, this);
 	}
 }
 
@@ -670,7 +686,7 @@ void Transaction::rollback(thread_db* tdbb, bool retain)
 	if (!retain)
 	{
 		detachFromJrdTran();
-		m_connection.deleteTransaction(this);
+		m_connection.deleteTransaction(tdbb, this);
 	}
 
 	if (status->getState() & IStatus::STATE_ERRORS) {
@@ -710,7 +726,7 @@ Transaction* Transaction::getTransaction(thread_db* tdbb, Connection* conn, TraS
 		}
 		catch (const Exception&)
 		{
-			conn->deleteTransaction(ext_tran);
+			conn->deleteTransaction(tdbb, ext_tran);
 			throw;
 		}
 	}
@@ -913,7 +929,7 @@ bool Statement::fetch(thread_db* tdbb, const ValueListNode* out_params)
 	return true;
 }
 
-void Statement::close(thread_db* tdbb)
+void Statement::close(thread_db* tdbb, bool invalidTran)
 {
 	// we must stuff exception if and only if this is the first time it occurs
 	// once we stuff exception we must punt
@@ -942,6 +958,9 @@ void Statement::close(thread_db* tdbb)
 		unBindFromRequest();
 	}
 
+	if (invalidTran)
+		m_transaction = NULL;
+
 	if (m_transaction && m_transaction->getScope() == traAutonomous)
 	{
 		bool commitFailed = false;
diff --git a/src/jrd/extds/ExtDS.h b/src/jrd/extds/ExtDS.h
index 7b3c7f30d9..62e2db3946 100644
--- a/src/jrd/extds/ExtDS.h
+++ b/src/jrd/extds/ExtDS.h
@@ -201,7 +201,7 @@ public:
 	// transaction into m_transactions array and delete not needed transaction
 	// immediately (as we didn't pool transactions)
 	Transaction* createTransaction();
-	void deleteTransaction(Transaction* tran);
+	void deleteTransaction(Jrd::thread_db* tdbb, Transaction* tran);
 
 	// Statements management within connection scope : put newly created
 	// statement into m_statements array, but don't delete freed statement
@@ -325,7 +325,7 @@ public:
 	void open(Jrd::thread_db* tdbb, Transaction* tran,
 		const Firebird::MetaName* const* in_names, const Jrd::ValueListNode* in_params, bool singleton);
 	bool fetch(Jrd::thread_db* tdbb, const Jrd::ValueListNode* out_params);
-	void close(Jrd::thread_db* tdbb);
+	void close(Jrd::thread_db* tdbb, bool invalidTran = false);
 	void deallocate(Jrd::thread_db* tdbb);
 
 	const Firebird::string& getSql() const { return m_sql; }