Index: /trunk/src/VBox/Devices/EFI/DevSmc.cpp
===================================================================
--- /trunk/src/VBox/Devices/EFI/DevSmc.cpp	(revision 71775)
+++ /trunk/src/VBox/Devices/EFI/DevSmc.cpp	(revision 71776)
@@ -1288,4 +1288,5 @@
     PDEVSMC pThis = PDMINS_2_DATA(pDevIns, PDEVSMC);
     uint32_t uReg = Port - SMC_PORT_FIRST;
+    AssertReturn(uReg < RT_ELEMENTS(g_aSmcRegs), VERR_INTERNAL_ERROR_3); /* impossible*/
     int rc = g_aSmcRegs[uReg].pfnWrite(pThis, uReg, u32);
 
@@ -1331,4 +1332,5 @@
      */
     uint32_t uReg = Port - SMC_PORT_FIRST;
+    AssertReturn(uReg < RT_ELEMENTS(g_aSmcRegs), VERR_INTERNAL_ERROR_3); /* impossible*/
     Log2(("smcIoPortRead: %#04x read access: LB %u\n", uReg, cb));
     uint8_t bValue = 0xff;