diff options
| author | iximeow <me@iximeow.net> | 2020-08-02 21:04:59 -0700 |
|---|---|---|
| committer | iximeow <me@iximeow.net> | 2020-08-09 01:38:57 -0700 |
| commit | aa3df6a360551c2a770863c4324101db7b22f79f (patch) | |
| tree | 016ff09f50a35f877151b16a1d27aa6dcffb4b4f | |
| parent | 4112c2282a207ab0738db44dfc69caf68fe50de9 (diff) | |
handle bad fe/ff opcode cases better
| -rw-r--r-- | src/long_mode/mod.rs | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/src/long_mode/mod.rs b/src/long_mode/mod.rs index b620092..ef7f8c9 100644 --- a/src/long_mode/mod.rs +++ b/src/long_mode/mod.rs @@ -5966,20 +5966,22 @@ fn read_operands<T: Iterator<Item=u8>>(decoder: &InstDecoder, mut bytes_iter: T, }, OperandCode::ModRM_0xfe_Eb => { instruction.operands[0] = mem_oper; + let r = (modrm >> 3) & 7; + if r >= 2 { + return Err(DecodeError::InvalidOpcode); + } instruction.opcode = [ Opcode::INC, Opcode::DEC, - Opcode::Invalid, - Opcode::Invalid, - Opcode::Invalid, - Opcode::Invalid, - Opcode::Invalid, - Opcode::Invalid - ][((modrm >> 3) & 7) as usize]; + ][r as usize]; instruction.operand_count = 1; } OperandCode::ModRM_0xff_Ev => { instruction.operands[0] = mem_oper; + let r = (modrm >> 3) & 7; + if r == 7 { + return Err(DecodeError::InvalidOpcode); + } let opcode = [ Opcode::INC, Opcode::DEC, @@ -5988,8 +5990,7 @@ fn read_operands<T: Iterator<Item=u8>>(decoder: &InstDecoder, mut bytes_iter: T, Opcode::JMP, Opcode::JMPF, Opcode::PUSH, - Opcode::Invalid - ][((modrm >> 3) & 7) as usize]; + ][r as usize]; if instruction.operands[0] == OperandSpec::RegMMM { if opcode == Opcode::CALL || opcode == Opcode::JMP { instruction.modrm_mmm.bank = RegisterBank::Q; |