2.6.24.3

 mm

diff --git a/mm/memory.c b/mm/memory.c
index 4b0144b..da8b74b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -980,6 +980,8 @@ int get_user_pages(struct task_struct *tsk, struct mm_struct *mm,
    int i;
    unsigned int vm_flags;
 
+   if (len <= 0)
+      return 0;
    /* 
     * Require read or write permissions.
     * If 'force' is set, we only require the "MAY" flags.