wininet: Fixed handling NULL buffer in INTERNET_OPTION_PROXY queries.

dlls/wininet/internet.c

@@ -821,7 +821,7 @@ static DWORD APPINFO_QueryOption(object_header_t *hdr, DWORD option, void *buffe
                 proxyBytesRequired = (lstrlenW(ai->proxy) + 1) * sizeof(WCHAR);
             if (ai->proxyBypass)
                 proxyBypassBytesRequired = (lstrlenW(ai->proxyBypass) + 1) * sizeof(WCHAR);
-            if (*size < sizeof(INTERNET_PROXY_INFOW) + proxyBytesRequired + proxyBypassBytesRequired)
+            if (!pi || *size < sizeof(INTERNET_PROXY_INFOW) + proxyBytesRequired + proxyBypassBytesRequired)
             {
                 *size = sizeof(INTERNET_PROXY_INFOW) + proxyBytesRequired + proxyBypassBytesRequired;
                 return ERROR_INSUFFICIENT_BUFFER;
@@ -854,7 +854,7 @@ static DWORD APPINFO_QueryOption(object_header_t *hdr, DWORD option, void *buffe
             if (ai->proxyBypass)
                 proxyBypassBytesRequired = WideCharToMultiByte(CP_ACP, 0, ai->proxyBypass, -1,
                         NULL, 0, NULL, NULL);
-            if (*size < sizeof(INTERNET_PROXY_INFOA) + proxyBytesRequired + proxyBypassBytesRequired)
+            if (!pi || *size < sizeof(INTERNET_PROXY_INFOA) + proxyBytesRequired + proxyBypassBytesRequired)
             {
                 *size = sizeof(INTERNET_PROXY_INFOA) + proxyBytesRequired + proxyBypassBytesRequired;
                 return ERROR_INSUFFICIENT_BUFFER;

dlls/wininet/tests/internet.c

@@ -164,6 +164,12 @@ static void test_InternetQueryOptionA(void)
   int retval;
   BOOL res;
 
+  SetLastError(0xdeadbeef);
+  len = 0xdeadbeef;
+  retval = InternetQueryOptionA(NULL, INTERNET_OPTION_PROXY, NULL, &len);
+  ok(!retval && GetLastError() == ERROR_INSUFFICIENT_BUFFER, "Got wrong error %x(%u)\n", retval, GetLastError());
+  ok(len >= sizeof(INTERNET_PROXY_INFO) && len != 0xdeadbeef,"len = %u\n", len);
+
   hinet = InternetOpenA(useragent,INTERNET_OPEN_TYPE_DIRECT,NULL,NULL, 0);
   ok((hinet != 0x0),"InternetOpen Failed\n");