* include/grub/video.h (grub_video_register): Keep double-linked as

well as single-linked invariants.
	Reported by: qwertial.

ChangeLog

@@ -1,3 +1,9 @@
+2013-07-25  Vladimir Serbinenko  <phcoder@gmail.com>
+
+	* include/grub/video.h (grub_video_register): Keep double-linked as
+	well as single-linked invariants.
+	Reported by: qwertial.
+
 2013-07-25  Vladimir Serbinenko  <phcoder@gmail.com>
 
 	* grub-core/commands/nativedisk.c (get_uuid): Handle

include/grub/video.h

@@ -400,6 +400,10 @@ grub_video_register (grub_video_adapter_t adapter)
        p = &((*p)->next));
   adapter->next = *p;
   *p = adapter;
+
+  adapter->prev = p;
+  if (adapter->next)
+    adapter->next->prev = &adapter->next;
 }
 #endif