SERVER-37838 prevent crash with getMore and simultaneous stepdown

1 files changed, 3 insertions, 5 deletions

diff --git a/src/mongo/db/cursor_manager.cpp b/src/mongo/db/cursor_manager.cpp
index 092e95eedb0..03caf70537b 100644
--- a/src/mongo/db/cursor_manager.cpp
+++ b/src/mongo/db/cursor_manager.cpp
@@ -185,9 +185,8 @@ bool GlobalCursorIdCache::killCursor(OperationContext* opCtx, CursorId id, bool
     if (CursorManager::isGloballyManagedCursor(id)) {
         auto pin = globalCursorManager->pinCursor(opCtx, id, CursorManager::kNoCheckSession);
         if (!pin.isOK()) {
-            invariant(pin == ErrorCodes::CursorNotFound || pin == ErrorCodes::Unauthorized);
-            // No such cursor.  TODO: Consider writing to audit log here (even though we don't
-            // have a namespace).
+            // Either the cursor doesn't exist, or it was killed during the last time it was being
+            // used, and was cleaned up after this call. Either way, we cannot kill it.
             return false;
         }
         nss = pin.getValue().getCursor()->nss();
@@ -196,8 +195,7 @@ bool GlobalCursorIdCache::killCursor(OperationContext* opCtx, CursorId id, bool
         uint32_t nsid = idFromCursorId(id);
         IdToNssMap::const_iterator it = _idToNss.find(nsid);
         if (it == _idToNss.end()) {
-            // No namespace corresponding to this cursor id prefix.  TODO: Consider writing to
-            // audit log here (even though we don't have a namespace).
+            // No namespace corresponding to this cursor id prefix.
             return false;
         }
         nss = it->second;