From 77efbb834a5119b93e656dce6189f36df89645bb Mon Sep 17 00:00:00 2001
From: iximeow <me@iximeow.net>
Date: Sat, 3 Jul 2021 09:41:31 -0700
Subject: reject instructions when their opcode is `Invalid`

the evex route would allow "valid" instructions that have the opcode
`invalid`. this is.. not correct.
---
 src/long_mode/display.rs | 5 -----
 src/long_mode/mod.rs     | 2 +-
 src/shared/evex.in       | 3 +++
 3 files changed, 4 insertions(+), 6 deletions(-)

(limited to 'src')

diff --git a/src/long_mode/display.rs b/src/long_mode/display.rs
index e60645b..049b96d 100644
--- a/src/long_mode/display.rs
+++ b/src/long_mode/display.rs
@@ -1806,11 +1806,6 @@ impl Opcode {
     }
 }
 
-    // AVX512CD
-
-
-    // MPX
-
 impl <T: fmt::Write, Y: YaxColors> Colorize<T, Y> for Opcode {
     fn colorize(&self, colors: &Y, out: &mut T) -> fmt::Result {
         match self {
diff --git a/src/long_mode/mod.rs b/src/long_mode/mod.rs
index 769706f..41e24e6 100644
--- a/src/long_mode/mod.rs
+++ b/src/long_mode/mod.rs
@@ -6967,7 +6967,7 @@ fn read_0f3a_opcode(opcode: u8, prefixes: &mut Prefixes) -> OpcodeRecord {
             0x61 => OpcodeRecord(Interpretation::Instruction(Opcode::PCMPESTRI), OperandCode::G_E_xmm_Ib),
             0x62 => OpcodeRecord(Interpretation::Instruction(Opcode::PCMPISTRM), OperandCode::G_E_xmm_Ib),
             0x63 => OpcodeRecord(Interpretation::Instruction(Opcode::PCMPISTRI), OperandCode::G_E_xmm_Ib),
-            0xcc => OpcodeRecord(Interpretation::Instruction(Opcode::SHA1RNDS4), OperandCode::G_E_xmm_Ib),
+//            0xcc => OpcodeRecord(Interpretation::Instruction(Opcode::SHA1RNDS4), OperandCode::G_E_xmm_Ib),
             0xce => OpcodeRecord(Interpretation::Instruction(Opcode::GF2P8AFFINEQB), OperandCode::G_E_xmm_Ub),
             0xcf => OpcodeRecord(Interpretation::Instruction(Opcode::GF2P8AFFINEINVQB), OperandCode::G_E_xmm_Ub),
             0xdf => OpcodeRecord(Interpretation::Instruction(Opcode::AESKEYGENASSIST), OperandCode::G_E_xmm_Ub),
diff --git a/src/shared/evex.in b/src/shared/evex.in
index 2bcd2f4..f9574db 100644
--- a/src/shared/evex.in
+++ b/src/shared/evex.in
@@ -86,6 +86,9 @@ pub(crate) fn read_evex<T: Reader<<Arch as yaxpeax_arch::Arch>::Address, <Arch a
         }
         instruction.prefixes.apply_compressed_disp(false);
       }
+      if instruction.opcode == Opcode::Invalid {
+        return Err(DecodeError::InvalidOpcode);
+      }
       // TODO: apply rp and bp?
     } else {
       return Err(DecodeError::InvalidOpcode);
-- 
cgit v1.1