diff --git a/src/x11/meta-selection-source-x11.c b/src/x11/meta-selection-source-x11.c
index 35451542b..a154b21af 100644
--- a/src/x11/meta-selection-source-x11.c
+++ b/src/x11/meta-selection-source-x11.c
@@ -155,7 +155,7 @@ atoms_to_mimetypes (MetaX11Display *display,
 
   for (i = 0; i < n_atoms; i++)
     {
-      const gchar *mimetype;
+      char *mimetype;
 
       meta_x11_error_trap_push (display);
       mimetype = XGetAtomName (xdisplay, atoms[i]);
@@ -170,6 +170,8 @@ atoms_to_mimetypes (MetaX11Display *display,
       text_plain_found |= strcmp (mimetype, "text/plain") == 0;
       utf8_string_found |= strcmp (mimetype, "UTF8_STRING") == 0;
       string_found |= strcmp (mimetype, "STRING") == 0;
+
+      XFree (mimetype);
     }
 
   /* Ensure non-x11 clients get well-known mimetypes */
diff --git a/src/x11/meta-x11-selection.c b/src/x11/meta-x11-selection.c
index 0700fb506..66a1d1803 100644
--- a/src/x11/meta-x11-selection.c
+++ b/src/x11/meta-x11-selection.c
@@ -185,7 +185,7 @@ meta_x11_selection_find_target (MetaX11Display     *x11_display,
 {
   Display *xdisplay = meta_x11_display_get_xdisplay (x11_display);
   GList* mimetypes = NULL;
-  const gchar *atom_name;
+  char *atom_name;
   char *retval;
 
   mimetypes = meta_selection_get_mimetypes (selection, selection_type);
@@ -213,6 +213,7 @@ meta_x11_selection_find_target (MetaX11Display     *x11_display,
     }
 
   g_list_free_full (mimetypes, g_free);
+  XFree (atom_name);
 
   return retval;
 }