fix race condition between dropping database or colletion and map/reduce cleanup SERVER-2542

1 files changed, 3 insertions, 0 deletions

diff --git a/db/commands/mr.cpp b/db/commands/mr.cpp
index 71b09b0511d..16c604acfa6 100644
--- a/db/commands/mr.cpp
+++ b/db/commands/mr.cpp
@@ -633,6 +633,9 @@ namespace mongo {
 
                 killCurrentOp.checkForInterrupt();
             }
+            
+            // we need to release here since we temp release below
+            cursor.release();
 
             {
                 dbtempreleasecond tl;