virsh: edit: don't leak XML string on reedit or redefine

Free the old XML strings before overwriting them if the user
has chosen to reedit the file or force the redefinition.

Found by Alex Jia trying to reproduce another bug:
https://bugzilla.redhat.com/show_bug.cgi?id=977430#c3

diff --git a/tools/virsh-edit.c b/tools/virsh-edit.c
index 9d612a3e3ba3d3f2c49317f2c1ddac29163ce114..bb79853e086906562a0717f6afbd9dd2caa8a5ce 100644 (file)
--- a/tools/virsh-edit.c
+++ b/tools/virsh-edit.c
@@ -86,6 +86,7 @@ reedit:
         goto edit_cleanup;
 
     /* Read back the edited file. */
+    VIR_FREE(doc_edited);
     doc_edited = vshEditReadBackFile(ctl, tmp);
     if (!doc_edited)
         goto edit_cleanup;
@@ -102,6 +103,7 @@ redefine:
      * it was being edited?  This also catches problems such as us
      * losing a connection or the object going away.
      */
+    VIR_FREE(doc_reread);
     doc_reread = (EDIT_GET_XML);
     if (!doc_reread)
         goto edit_cleanup;