[Xen-changelog] [xen-3.4-testing] x86_emulate: Fixes for 'mov rm16, sreg'

["Xen patchbot-3.4-testing" <patchbot-3.4-testing@xxxxxxxxxxxxxxxxxxx>]

# HG changeset patch
# User Keir Fraser <keir.fraser@xxxxxxxxxx>
# Date 1250694095 -3600
# Node ID 090e394202d0bb0089abc5e5276ed7fda283567d
# Parent  daf1ff2c7dbd59b2ab31e6427be58ffdc14e10fd
x86_emulate: Fixes for 'mov rm16,sreg'

1. Memory reads should be 16 bits only
2. Attempt to load %cs should result in #UD

Signed-off-by: Keir Fraser <keir.fraser@xxxxxxxxxx>
xen-unstable changeset:   20035:3fe64f43944f
xen-unstable date:        Fri Aug 07 10:53:22 2009 +0100
---
 xen/arch/x86/x86_emulate/x86_emulate.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletion(-)

diff -r daf1ff2c7dbd -r 090e394202d0 xen/arch/x86/x86_emulate/x86_emulate.c
--- a/xen/arch/x86/x86_emulate/x86_emulate.c    Wed Aug 19 16:01:08 2009 +0100
+++ b/xen/arch/x86/x86_emulate/x86_emulate.c    Wed Aug 19 16:01:35 2009 +0100
@@ -113,7 +113,7 @@ static uint8_t opcode_table[256] = {
     ByteOp|DstMem|SrcReg|ModRM|Mov, DstMem|SrcReg|ModRM|Mov,
     ByteOp|DstReg|SrcMem|ModRM|Mov, DstReg|SrcMem|ModRM|Mov,
     DstMem|SrcReg|ModRM|Mov, DstReg|SrcNone|ModRM,
-    DstReg|SrcMem|ModRM|Mov, DstMem|SrcNone|ModRM|Mov,
+    DstReg|SrcMem16|ModRM|Mov, DstMem|SrcNone|ModRM|Mov,
     /* 0x90 - 0x97 */
     ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
     ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps,
@@ -2017,6 +2017,7 @@ x86_emulate(
     case 0x8e: /* mov r/m,Sreg */ {
         enum x86_segment seg = decode_segment(modrm_reg);
         generate_exception_if(seg == decode_segment_failed, EXC_UD, -1);
+        generate_exception_if(seg == x86_seg_cs, EXC_UD, -1);
         if ( (rc = load_seg(seg, (uint16_t)src.val, ctxt, ops)) != 0 )
             goto done;
         if ( seg == x86_seg_ss )

_______________________________________________
Xen-changelog mailing list
Xen-changelog@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-changelog