From 8bd124874043725b71445d2992939745ef378ccb Mon Sep 17 00:00:00 2001
From: taoshuning <616811991@qq.com>
Date: Wed, 26 Jul 2023 13:12:22 +0000
Subject: [PATCH] Add defensive for log restore mysql provider access
 concurrency control

---
 src/share/ob_log_restore_proxy.cpp | 13 ++++++++++---
 src/share/ob_log_restore_proxy.h   |  6 ++++++
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/src/share/ob_log_restore_proxy.cpp b/src/share/ob_log_restore_proxy.cpp
index d4b7e56c5b..1db1f94e30 100644
--- a/src/share/ob_log_restore_proxy.cpp
+++ b/src/share/ob_log_restore_proxy.cpp
@@ -65,11 +65,11 @@ namespace share
   } while (OB_FAIL(ret) && retry_time++ < server_prover_.get_server_count() - 1);
 
 
-ObLogRestoreMySQLProvider::ObLogRestoreMySQLProvider() : server_list_() {}
+ObLogRestoreMySQLProvider::ObLogRestoreMySQLProvider() : server_list_(), lock_() {}
 
 ObLogRestoreMySQLProvider::~ObLogRestoreMySQLProvider()
 {
-  server_list_.reset();
+  destroy();
 }
 
 int ObLogRestoreMySQLProvider::init(const common::ObIArray<common::ObAddr> &server_list)
@@ -80,6 +80,7 @@ int ObLogRestoreMySQLProvider::init(const common::ObIArray<common::ObAddr> &serv
 int ObLogRestoreMySQLProvider::set_restore_source_server(const common::ObIArray<common::ObAddr> &server_list)
 {
   int ret = OB_SUCCESS;
+  WLockGuard guard(lock_);
   if (OB_UNLIKELY(server_list.count() <= 0)) {
     ret = OB_INVALID_ARGUMENT;
     LOG_WARN("invalid argument", K(server_list));
@@ -90,15 +91,20 @@ int ObLogRestoreMySQLProvider::set_restore_source_server(const common::ObIArray<
 }
 void ObLogRestoreMySQLProvider::destroy()
 {
+  WLockGuard guard(lock_);
   server_list_.reset();
 }
 
 int ObLogRestoreMySQLProvider::get_server(const int64_t svr_idx, common::ObAddr &server)
 {
+  RLockGuard guard(lock_);
   int ret = OB_SUCCESS;
-  if (OB_UNLIKELY(svr_idx < 0 || svr_idx >= server_list_.count())) {
+  if (OB_UNLIKELY(svr_idx < 0)) {
     ret = OB_INVALID_INDEX;
     LOG_WARN("get_server invalid index", K(svr_idx));
+  } else if (OB_UNLIKELY(svr_idx >= server_list_.count())) {
+    ret = OB_ENTRY_NOT_EXIST;
+    LOG_WARN("svr_idx out of range", K(svr_idx), K(server_list_));
   } else {
     server = server_list_.at(svr_idx);
   }
@@ -107,6 +113,7 @@ int ObLogRestoreMySQLProvider::get_server(const int64_t svr_idx, common::ObAddr
 
 int64_t ObLogRestoreMySQLProvider::get_server_count() const
 {
+  RLockGuard guard(lock_);
   return server_list_.count();
 }
 
diff --git a/src/share/ob_log_restore_proxy.h b/src/share/ob_log_restore_proxy.h
index 7b345aa641..5017a04283 100644
--- a/src/share/ob_log_restore_proxy.h
+++ b/src/share/ob_log_restore_proxy.h
@@ -49,8 +49,14 @@ public:
   int prepare_refresh() override;
   int end_refresh() override;
 
+private:
+  typedef common::SpinRWLock RWLock;
+  typedef common::SpinRLockGuard  RLockGuard;
+  typedef common::SpinWLockGuard  WLockGuard;
+
 private:
   common::ObArray<common::ObAddr> server_list_;
+  mutable RWLock lock_;
 
 private:
   DISALLOW_COPY_AND_ASSIGN(ObLogRestoreMySQLProvider);