Add more boundary checking to sse3/4 parsing

ssse3 uses tables with only two entries per op, but it is indexed
with b1 which can contain variables upto 3. This happens when ssse3
or sse4 are used with REP* prefixes.

Add boundary checking for this case.
Signed-off-by: NAndi Kleen <ak@linux.intel.com>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>

target-i386/translate.c

@@ -3472,6 +3472,9 @@ static void gen_sse(DisasContext *s, int b, target_ulong pc_start, int rex_r)
         case 0x171: /* shift xmm, im */
         case 0x172:
         case 0x173:
+            if (b1 >= 2) {
+	        goto illegal_op;
+            }
             val = ldub_code(s->pc++);
             if (is_xmm) {
                 gen_op_movl_T0_im(val);
@@ -3699,6 +3702,9 @@ static void gen_sse(DisasContext *s, int b, target_ulong pc_start, int rex_r)
             rm = modrm & 7;
             reg = ((modrm >> 3) & 7) | rex_r;
             mod = (modrm >> 6) & 3;
+            if (b1 >= 2) {
+                goto illegal_op;
+            }
 
             sse_op2 = sse_op_table6[b].op[b1];
             if (!sse_op2)
@@ -3798,6 +3804,9 @@ static void gen_sse(DisasContext *s, int b, target_ulong pc_start, int rex_r)
             rm = modrm & 7;
             reg = ((modrm >> 3) & 7) | rex_r;
             mod = (modrm >> 6) & 3;
+            if (b1 >= 2) {
+                goto illegal_op;
+            }
 
             sse_op2 = sse_op_table7[b].op[b1];
             if (!sse_op2)