AOF rewrite: set iterator var to NULL when freed.

The cleanup code expects that if 'di' is not NULL, it is a valid
iterator that should be freed.

The result of this bug was a crash of the AOF rewriting process if an
error occurred after the DBs data are written and the iterator is no
longer valid.

1 files changed, 1 insertions, 0 deletions

diff --git a/src/aof.c b/src/aof.c
index 90b67fd9c..63bde53cc 100644
--- a/src/aof.c
+++ b/src/aof.c
@@ -1038,6 +1038,7 @@ int rewriteAppendOnlyFile(char *filename) {
             }
         }
         dictReleaseIterator(di);
+        di = NULL;
     }
 
     /* Make sure data will not remain on the OS's output buffers */