diff options
author | iximeow <me@iximeow.net> | 2021-07-03 13:41:33 -0700 |
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committer | iximeow <me@iximeow.net> | 2021-07-03 13:43:39 -0700 |
commit | 4ef72a72b2984bcca177724b65cf7290411c1ea0 (patch) | |
tree | 1fa8c178f4aeb5a83659e22a7e13006230447171 /src/shared | |
parent | 7796f7e088c5aa878cfb61b5a885b64daf390808 (diff) |
enforce reserved evex prefix bits
Diffstat (limited to 'src/shared')
-rw-r--r-- | src/shared/evex.in | 9 |
1 files changed, 8 insertions, 1 deletions
diff --git a/src/shared/evex.in b/src/shared/evex.in index b9a77e8..989d463 100644 --- a/src/shared/evex.in +++ b/src/shared/evex.in @@ -14,6 +14,14 @@ pub(crate) fn read_evex<T: Reader<<Arch as yaxpeax_arch::Arch>::Address, <Arch a let evex_byte_two = words.next().ok().ok_or(DecodeError::ExhaustedInput)?; let evex_byte_three = words.next().ok().ok_or(DecodeError::ExhaustedInput)?; let p = evex_byte_two & 0x03; + if evex_byte_one & 0x0c != 0 { + // the two bits above `m` are reserved and must be 0 + return Err(DecodeError::InvalidOpcode); + } + if evex_byte_two & 0x04 == 0 { + // the one bit above `p` is reserved and must be 1 + return Err(DecodeError::InvalidOpcode); + } let m = evex_byte_one & 0x03; if m == 0 { return Err(DecodeError::InvalidOpcode); @@ -340,7 +348,6 @@ pub(crate) fn read_evex_operands<T: Reader<<Arch as yaxpeax_arch::Arch>::Address set_reg_sizes(instruction, RegisterBank::X); } generated::EVEXOperandCode::Gm_V_Ed_LL_sae => { - deny_vex_reg(instruction)?; check_mask_reg(instruction)?; let modrm = read_modrm(words)?; |