From 083392fa158e625d1e4e2bc9c7e4293a06fe2a9c Mon Sep 17 00:00:00 2001
From: daan <daanl@outlook.com>
Date: Mon, 6 Apr 2020 13:42:39 -0700
Subject: [PATCH] add padding check in usable size

---
 src/alloc.c                 |  3 ++-
 test/main-override-static.c | 14 +++++++-------
 2 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/alloc.c b/src/alloc.c
index bcd94673..62445040 100644
--- a/src/alloc.c
+++ b/src/alloc.c
@@ -213,7 +213,8 @@ static bool mi_page_decode_padding(const mi_page_t* page, const mi_block_t* bloc
 static size_t mi_page_usable_size_of(const mi_page_t* page, const mi_block_t* block) {
   size_t bsize;
   size_t delta;
-  bool ok = mi_page_decode_padding(page, block, &delta, &bsize);
+  bool ok = mi_page_decode_padding(page, block, &delta, &bsize);  
+  if (!ok) { mi_check_padding(page, block); }
   mi_assert_internal(ok); mi_assert_internal(delta <= bsize);
   return (ok ? bsize - delta : 0);
 }
diff --git a/test/main-override-static.c b/test/main-override-static.c
index c7c10ddc..ecf61468 100644
--- a/test/main-override-static.c
+++ b/test/main-override-static.c
@@ -17,9 +17,9 @@ int main() {
   mi_version();
 
   // detect double frees and heap corruption
-  double_free1();
-  double_free2();
-  corrupt_free();
+  // double_free1();
+  // double_free2();
+  // corrupt_free();
   block_overflow1();
   // dangling_ptr_write();
 
@@ -98,8 +98,8 @@ static void double_free2() {
 
 
 // Try to corrupt the heap through buffer overflow
-#define N   256
-#define SZ  64
+#define N   1024
+#define SZ  40
 
 static void corrupt_free() {
   void* p[N];
@@ -115,12 +115,12 @@ static void corrupt_free() {
   // try to corrupt the free list
   for (int i = 0; i < N; i++) {
     if (p[i] != NULL) {
-      memset(p[i], 0, SZ+8);
+      memset(p[i], 0, SZ+32);
     }
   }
   // allocate more.. trying to trigger an allocation from a corrupted entry
   // this may need many allocations to get there (if at all)
-  for (int i = 0; i < 4096; i++) {
+  for (int i = 0; i < 4*4096; i++) {
     malloc(SZ);
   }
 }