From 90d1fc066554c3dc988585f1fdd53b36c4ab8715 Mon Sep 17 00:00:00 2001
From: yungen-lu <70182238+yungen-lu@users.noreply.github.com>
Date: Sun, 27 Apr 2025 17:32:43 +0800
Subject: [PATCH] feat: finish lab5

---
 lab5/antiasan.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/lab5/antiasan.c b/lab5/antiasan.c
index 8a8936d..61e4a70 100644
--- a/lab5/antiasan.c
+++ b/lab5/antiasan.c
@@ -2,5 +2,11 @@
 
 void antiasan(unsigned long addr)
 {
-
+    // Calculate shadow memory address for gS (after gBadBuf)
+    unsigned long shadow_addr = ((addr + 0x87) >> 3) + 0x7fff8000;
+    
+    // Mark 16 bytes of shadow memory as valid (covers gS[0x17] to gS[0x27])
+    for (int i = 0; i < 16; i++) {
+        *(char *)(shadow_addr + i) = 0;
+    }
 }