MdePkg UefiDevicePathLib: Fix possible memory read/write cross boundary

The SSID field of a Wi-Fi device path node may not contain a NULL
termination.

Additonal handle is added to make sure no cross-boundary memory read/write
will occur.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Feng Tian <feng.tian@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18355 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Library/UefiDevicePathLib/DevicePathToText.c

@@ -1616,9 +1616,14 @@ DevPathToTextWiFi (
   )
 {
   WIFI_DEVICE_PATH      *WiFi;
+  UINT8                 SSId[33];
 
   WiFi = DevPath;
-  UefiDevicePathLibCatPrint (Str, L"Wi-Fi(%a)", WiFi->SSId);
+
+  SSId[32] = '\0';
+  CopyMem (SSId, WiFi->SSId, 32);
+
+  UefiDevicePathLibCatPrint (Str, L"Wi-Fi(%a)", SSId);
 }
 
 /**