André Hentschel : mshtml: Fix possible NULL pointer access in heap_str*.

[Alexandre Julliard]

Module: wine
Branch: master
Commit: e9bfe83683266edcc2917e3d151254aefd4b070d
URL:    http://source.winehq.org/git/wine.git/?a=commit;h=e9bfe83683266edcc2917e3d15...

Author: André Hentschel <nerv(a)dawncrow.de>
Date:   Sat Nov 17 22:52:32 2012 +0100

mshtml: Fix possible NULL pointer access in heap_str*.

---

 dlls/mshtml/mshtml_private.h |   19 +++++++++++++------
 1 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/dlls/mshtml/mshtml_private.h b/dlls/mshtml/mshtml_private.h
index 6c7662e..f9c05f0 100644
--- a/dlls/mshtml/mshtml_private.h
+++ b/dlls/mshtml/mshtml_private.h
@@ -1033,7 +1033,8 @@ static inline LPWSTR heap_strdupW(LPCWSTR str)
 
         size = (strlenW(str)+1)*sizeof(WCHAR);
         ret = heap_alloc(size);
-        memcpy(ret, str, size);
+        if(ret)
+            memcpy(ret, str, size);
     }
 
     return ret;
@@ -1045,8 +1046,11 @@ static inline LPWSTR heap_strndupW(LPCWSTR str, unsigned len)
 
     if(str) {
         ret = heap_alloc((len+1)*sizeof(WCHAR));
-        memcpy(ret, str, len*sizeof(WCHAR));
-        ret[len] = 0;
+        if(ret)
+        {
+            memcpy(ret, str, len*sizeof(WCHAR));
+            ret[len] = 0;
+        }
     }
 
     return ret;
@@ -1061,7 +1065,8 @@ static inline char *heap_strdupA(const char *str)
 
         size = strlen(str)+1;
         ret = heap_alloc(size);
-        memcpy(ret, str, size);
+        if(ret)
+            memcpy(ret, str, size);
     }
 
     return ret;
@@ -1076,7 +1081,8 @@ static inline WCHAR *heap_strdupAtoW(const char *str)
 
         len = MultiByteToWideChar(CP_ACP, 0, str, -1, NULL, 0);
         ret = heap_alloc(len*sizeof(WCHAR));
-        MultiByteToWideChar(CP_ACP, 0, str, -1, ret, len);
+        if(ret)
+            MultiByteToWideChar(CP_ACP, 0, str, -1, ret, len);
     }
 
     return ret;
@@ -1089,7 +1095,8 @@ static inline char *heap_strdupWtoA(LPCWSTR str)
     if(str) {
         DWORD size = WideCharToMultiByte(CP_ACP, 0, str, -1, NULL, 0, NULL, NULL);
         ret = heap_alloc(size);
-        WideCharToMultiByte(CP_ACP, 0, str, -1, ret, size, NULL, NULL);
+        if(ret)
+            WideCharToMultiByte(CP_ACP, 0, str, -1, ret, size, NULL, NULL);
     }
 
     return ret;