[PATCH 1/1] ntdll: Match Windows used block filling.

[Paul Gofman]

From: Paul Gofman

---
 dlls/kernel32/tests/heap.c | 41 ++++++++++++++++++++++++++++++++++++++
 dlls/ntdll/heap.c          |  6 ++++--
 2 files changed, 45 insertions(+), 2 deletions(-)

diff --git a/dlls/kernel32/tests/heap.c b/dlls/kernel32/tests/heap.c
index 59a82c0c579..a1d72302098 100644
--- a/dlls/kernel32/tests/heap.c
+++ b/dlls/kernel32/tests/heap.c
@@ -3270,8 +3270,49 @@ static void test_heap_checks( DWORD flags )
     ret = HeapFree( GetProcessHeap(), 0, p );
     ok( ret, "HeapFree failed\n" );

+    if (flags & HEAP_FREE_CHECKING_ENABLED)
+    {
+        void *p_prev;
+        SIZE_T count;
+
+        p = pHeapAlloc( GetProcessHeap(), 0, 39 );
+        ok( !!p, "HeapAlloc failed\n" );
+        for (i = 0; i < 39 / sizeof(int); ++i)
+            ok( ((unsigned int *)p)[i] == 0xbaadf00d, "got %#x, i %Iu.\n", ((unsigned int *)p)[i], i );
+        memset( p, 0xcc, 39 );
+
+        p_prev = p;
+        count = 5;
+        p = pHeapReAlloc( GetProcessHeap(), 0, p, 39 + count * 4 );
+        ok( !!p, "got NULL.\n" );
+
+        winetest_push_context( "in place %d", p == p_prev);
+        if (p == p_prev)
+        {
+            if (flags & HEAP_TAIL_CHECKING_ENABLED)
+                ok( p[39] == 0xab, "got %#x.\n", p[39] );
+            for (i = 0; i < count - 1; ++i)
+                ok( ((unsigned int *)p)[10 + i] == 0xbaadf00d, "got %#x, i %Iu.\n", ((unsigned int *)p)[10 + i], i );
+        }
+        else
+        {
+            ok( p[39] == 0xba, "got %#x.\n", p[39] );
+            for (i = 0; i < count - 1; ++i)
+                ok( ((unsigned int *)p)[10 + i] == 0xbaadf00d, "got %#x, i %Iu.\n", ((unsigned int *)p)[10 + i], i );
+        }
+        winetest_pop_context();
+
+        ret = pHeapFree( GetProcessHeap(), 0, p );
+        ok( ret, "failed.\n" );
+    }
+
     p = HeapAlloc( GetProcessHeap(), 0, 37 );
     ok( p != NULL, "HeapAlloc failed\n" );
+    if (flags & HEAP_FREE_CHECKING_ENABLED)
+    {
+        for (i = 0; i < 37 / sizeof(int); ++i)
+            ok( ((unsigned int *)p)[i] == 0xbaadf00d, "got %#x, i %Iu.\n", ((unsigned int *)p)[i], i );
+    }
     memset( p, 0xcc, 37 );

ret = pHeapFree( GetProcessHeap(), 0, p );
diff --git a/dlls/ntdll/heap.c b/dlls/ntdll/heap.c
index aca8e7181a8..5ce7f8fad2f 100644
--- a/dlls/ntdll/heap.c
+++ b/dlls/ntdll/heap.c
@@ -139,7 +139,7 @@ C_ASSERT( sizeof(ARENA_LARGE) == 4 * BLOCK_ALIGN );
 #define BLOCK_TYPE_FREE        'F'
 #define BLOCK_TYPE_LARGE       'L'

-#define BLOCK_FILL_USED        0x55
+#define BLOCK_FILL_USED        0xbaadf00d
 #define BLOCK_FILL_TAIL        0xab
 #define BLOCK_FILL_FREE        0xfeeefeee

@@ -513,6 +513,7 @@ static inline void mark_block_tail( struct block *block, DWORD flags )
 static inline void initialize_block( struct block *block, SIZE_T old_size, SIZE_T size, DWORD flags )
 {
     char *data = (char *)(block + 1);
+    SIZE_T i;

if (size <= old_size) return;

@@ -524,7 +525,8 @@ static inline void initialize_block( struct block *block, SIZE_T old_size, SIZE_
     else if (flags & HEAP_FREE_CHECKING_ENABLED)
     {
         valgrind_make_writable( data + old_size, size - old_size );
-        memset( data + old_size, BLOCK_FILL_USED, size - old_size );
+        i = ROUND_SIZE( old_size, sizeof(DWORD) - 1 ) / sizeof(DWORD);
+        for (; i < size / sizeof(DWORD); ++i) ((DWORD *)data)[i] = BLOCK_FILL_USED;
     }
 }