; Safer 'x-display-monitor-attributes-list'

* src/xfns.c (Fx_display_monitor_attributes_list): Don't access
more elements in monitor_frames than there are monitors reported
by 'gdk_display_get_n_monitors' or 'gdk_screen_get_n_monitors'.
(Bug#79941)

1 files changed, 2 insertions, 1 deletions

diff --git a/src/xfns.c b/src/xfns.c
index 70a4b6d5509..f960f36e24d 100644
--- a/src/xfns.c
+++ b/src/xfns.c
@@ -6648,7 +6648,8 @@ Internal use only, use `display-monitor-attributes-list' instead.  */)
 #else
           i = gdk_screen_get_monitor_at_window (gscreen, gwin);
 #endif
-          ASET (monitor_frames, i, Fcons (frame, AREF (monitor_frames, i)));
+          if (0 <= i && i < n_monitors)
+            ASET (monitor_frames, i, Fcons (frame, AREF (monitor_frames, i)));
         }
     }