From 9dc3f5e6cc9d87c0cd419966ca794a7c15a6e5fe Mon Sep 17 00:00:00 2001
From: Dmitry Yemanov <dyemanov@users.noreply.github.com>
Date: Tue, 31 Jan 2023 12:01:59 +0300
Subject: [PATCH] Postfix for #7446: never attempt to delete savepoints
 belonging to a different transaction

---
 src/dsql/StmtNodes.cpp |  9 +++++++--
 src/jrd/req.h          | 35 ++++++++++++++++++++++++++++++++++-
 2 files changed, 41 insertions(+), 3 deletions(-)

diff --git a/src/dsql/StmtNodes.cpp b/src/dsql/StmtNodes.cpp
index 7b89d06ea6..453dc7ee80 100644
--- a/src/dsql/StmtNodes.cpp
+++ b/src/dsql/StmtNodes.cpp
@@ -3712,6 +3712,7 @@ const StmtNode* InAutonomousTransactionNode::execute(thread_db* tdbb, jrd_req* r
 											   org_transaction->tra_lock_timeout,
 											   org_transaction);
 
+		request->pushTransaction(org_transaction);
 		TRA_attach_request(transaction, request);
 		tdbb->setTransaction(transaction);
 
@@ -3722,12 +3723,13 @@ const StmtNode* InAutonomousTransactionNode::execute(thread_db* tdbb, jrd_req* r
 		}
 		catch (Exception&)
 		{
+			TRA_detach_request(request);
+			request->popTransaction();
 			TRA_attach_request(org_transaction, request);
 			tdbb->setTransaction(org_transaction);
 			throw;
 		}
 
-		request->req_auto_trans.push(org_transaction);
 		impure->traNumber = transaction->tra_number;
 
 		VIO_start_save_point(tdbb, transaction);
@@ -3841,8 +3843,11 @@ const StmtNode* InAutonomousTransactionNode::execute(thread_db* tdbb, jrd_req* r
 	}
 
 	impure->traNumber = impure->savNumber = 0;
-	transaction = request->req_auto_trans.pop();
 
+	// Normally request is detached by commit/rollback, but they may fail.
+	// It should be done before request->popTransaction().
+	TRA_detach_request(request);
+	transaction = request->popTransaction();
 	TRA_attach_request(transaction, request);
 	tdbb->setTransaction(transaction);
 
diff --git a/src/jrd/req.h b/src/jrd/req.h
index 4f917303d4..eb9a60becf 100644
--- a/src/jrd/req.h
+++ b/src/jrd/req.h
@@ -164,6 +164,21 @@ private:
 
 class jrd_req : public pool_alloc<type_req>
 {
+	// Context data saved/restored with every new autonomous transaction
+
+	struct AutoTranCtx
+	{
+		AutoTranCtx() : m_transaction(NULL), m_savepoints(NULL)
+		{}
+
+		AutoTranCtx(jrd_tra* tran, Savepoint* save) :
+			m_transaction(tran), m_savepoints(save)
+		{}
+
+		jrd_tra* m_transaction;
+		Savepoint* m_savepoints;
+	};
+
 public:
 	jrd_req(Attachment* attachment, /*const*/ JrdStatement* aStatement,
 			Firebird::MemoryStats* parent_stats)
@@ -263,7 +278,7 @@ public:
 	ULONG req_src_column;
 
 	dsc*			req_domain_validation;	// Current VALUE for constraint validation
-	Firebird::Stack<jrd_tra*> req_auto_trans;	// Autonomous transactions
+	Firebird::Stack<AutoTranCtx> req_auto_trans;	// Autonomous transactions
 	SortOwner req_sorts;
 	Firebird::Array<record_param> req_rpb;	// record parameter blocks
 	Firebird::Array<UCHAR> impureArea;		// impure area
@@ -294,6 +309,24 @@ public:
 		}
 		req_base_stats.assign(req_stats);
 	}
+
+	// Save context when switching to the autonomous transaction
+	void pushTransaction(jrd_tra* const transaction)
+	{
+		req_auto_trans.push(AutoTranCtx(transaction, req_proc_sav_point));
+		req_proc_sav_point = NULL;
+	}
+
+	// Restore context
+	jrd_tra* popTransaction()
+	{
+		fb_assert(!req_transaction); // must be detached
+
+		const AutoTranCtx tmp = req_auto_trans.pop();
+		req_proc_sav_point = tmp.m_savepoints;
+
+		return tmp.m_transaction;
+	}
 };
 
 // Flags for req_flags