From 14221efe4b551642b177b4be35b4659b43555840 Mon Sep 17 00:00:00 2001
From: Mael Guillossou <mael.guillossou@gmail.com>
Date: Thu, 18 Mar 2021 12:04:25 +0100
Subject: [PATCH] Check bit "long mode active"

---
 mythril/src/emulate/memio.rs | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/mythril/src/emulate/memio.rs b/mythril/src/emulate/memio.rs
index ddfc982..4d7a5a6 100644
--- a/mythril/src/emulate/memio.rs
+++ b/mythril/src/emulate/memio.rs
@@ -415,7 +415,11 @@ fn process_memio_op(
 
     let efer = vcpu.vmcs.read_field(vmcs::VmcsField::GuestIa32Efer)?;
     // TODO: 16bit support
-    let mode = if efer & 0x00000100 != 0 { 64 } else { 32 };
+    let mode = if efer & (1 << 8) != 0 && efer & (1 << 10) != 0 {
+        64
+    } else {
+        32
+    };
 
     let mut decoder =
         iced_x86::Decoder::new(mode, &bytes, iced_x86::DecoderOptions::NONE);