From f01772ca853e76d3076a561da3281034e3a46196 Mon Sep 17 00:00:00 2001
From: Marsman1996 <lqliuyuwei@outlook.com>
Date: Wed, 11 Sep 2024 16:23:21 +0800
Subject: [PATCH] Fix panic in Cursor::new by invalid Vaddr range

---
 ostd/src/mm/page_table/cursor.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ostd/src/mm/page_table/cursor.rs b/ostd/src/mm/page_table/cursor.rs
index 75b1bdb9d..ee0d3d927 100644
--- a/ostd/src/mm/page_table/cursor.rs
+++ b/ostd/src/mm/page_table/cursor.rs
@@ -141,7 +141,7 @@ where
     /// Note that this function does not ensure exclusive access to the claimed
     /// virtual address range. The accesses using this cursor may block or fail.
     pub fn new(pt: &'a PageTable<M, E, C>, va: &Range<Vaddr>) -> Result<Self, PageTableError> {
-        if !M::covers(va) {
+        if !M::covers(va) || va.is_empty() {
             return Err(PageTableError::InvalidVaddrRange(va.start, va.end));
         }
         if va.start % C::BASE_PAGE_SIZE != 0 || va.end % C::BASE_PAGE_SIZE != 0 {