Changeset 65631 in vbox for trunk/src/VBox/VMM

Timestamp:

Feb 6, 2017 5:38:05 PM (8 years ago)

Author:

vboxsync

Message:

IEM: When loading a 16-bit stack from TSS, consistently force a 16-bit stack pointer.

File:

• trunk/src/VBox/VMM/VMMAll/IEMAll.cpp (modified) (2 diffs)

trunk/src/VBox/VMM/VMMAll/IEMAll.cpp

@@ -4574 +4574 @@
         if (rcStrict != VINF_SUCCESS)
             return rcStrict;
+        /* If the new SS is 16-bit, we are only going to use SP, not ESP. */
+        if (!DescSS.Legacy.Gen.u1DefBig)
+        {
+            Log(("iemRaiseXcptOrIntInProtMode: Forcing ESP=%#x to 16 bits\n", uNewEsp));
+            uNewEsp = (uint16_t)uNewEsp;
+        }
+
         Log7(("iemRaiseXcptOrIntInProtMode: New SS=%#x ESP=%#x (from TSS); current SS=%#x ESP=%#x\n", NewSS, uNewEsp, pCtx->ss.Sel, pCtx->esp));
 
@@ -4594 +4601 @@
         else
         {
-            if (   uNewEsp - 1 > (DescSS.Legacy.Gen.u4Type & X86_DESC_DB ? UINT32_MAX : UINT32_C(0xffff))
+            if (   uNewEsp - 1 > (DescSS.Legacy.Gen.u1DefBig ? UINT32_MAX : UINT16_MAX)
                 || uNewEsp - cbStackFrame < cbLimitSS + UINT32_C(1))
             {