SERVER-55681 Clustered collections should reject duplicate _id values

The WiredTigerSessionCache should not mix cursors with different
overwrite settings.

1 files changed, 7 insertions, 4 deletions

diff --git a/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp b/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
index 2f280c159c0..a627dd65d5b 100644
--- a/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
+++ b/src/mongo/db/storage/wiredtiger/wiredtiger_session_cache.cpp
@@ -111,10 +111,13 @@ void _openCursor(WT_SESSION* session,
 }
 }  // namespace
 
-WT_CURSOR* WiredTigerSession::getCachedCursor(const std::string& uri, uint64_t id) {
+WT_CURSOR* WiredTigerSession::getCachedCursor(uint64_t id, const std::string& config) {
     // Find the most recently used cursor
     for (CursorCache::iterator i = _cursors.begin(); i != _cursors.end(); ++i) {
-        if (i->_id == id) {
+        // Ensure that all properties of this cursor are identical to avoid mixing cursor
+        // configurations. Note that this uses an exact string match, so cursor configurations with
+        // parameters in different orders will not be considered equivalent.
+        if (i->_id == id && i->_config == config) {
             WT_CURSOR* c = i->_cursor;
             _cursors.erase(i);
             _cursorsOut++;
@@ -131,7 +134,7 @@ WT_CURSOR* WiredTigerSession::getNewCursor(const std::string& uri, const char* c
     return cursor;
 }
 
-void WiredTigerSession::releaseCursor(uint64_t id, WT_CURSOR* cursor) {
+void WiredTigerSession::releaseCursor(uint64_t id, WT_CURSOR* cursor, const std::string& config) {
     invariant(_session);
     invariant(cursor);
     _cursorsOut--;
@@ -139,7 +142,7 @@ void WiredTigerSession::releaseCursor(uint64_t id, WT_CURSOR* cursor) {
     invariantWTOK(cursor->reset(cursor));
 
     // Cursors are pushed to the front of the list and removed from the back
-    _cursors.push_front(WiredTigerCachedCursor(id, _cursorGen++, cursor));
+    _cursors.push_front(WiredTigerCachedCursor(id, _cursorGen++, cursor, config));
 
     // A negative value for wiredTigercursorCacheSize means to use hybrid caching.
     std::uint32_t cacheSize = abs(gWiredTigerCursorCacheSize.load());