[glib: 9/15] guri: Clear return values on error from g_uri_params_iter_next()

[Philip Withnall <pwithnall src gnome org>]

commit ceda9755dea78a74422aac06fdf3d83ea151dd46
Author: Philip Withnall <withnall endlessm com>
Date:   Thu Aug 6 14:03:54 2020 +0100

    guri: Clear return values on error from g_uri_params_iter_next()
    
    This reduces the chance of the caller accidentally double-freeing or
    use-after-free-ing something.
    
    Signed-off-by: Philip Withnall <withnall endlessm com>

 glib/guri.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/glib/guri.c b/glib/guri.c
index f0944a050..905130255 100644
--- a/glib/guri.c
+++ b/glib/guri.c
@@ -1973,6 +1973,12 @@ g_uri_params_iter_next (GUriParamsIter *iter,
   g_return_val_if_fail (iter != NULL, FALSE);
   g_return_val_if_fail (error == NULL || *error == NULL, FALSE);
 
+  /* Pre-clear these in case of failure or finishing. */
+  if (attribute)
+    *attribute = NULL;
+  if (value)
+    *value = NULL;
+
   if (ri->attr >= ri->end)
     return FALSE;