decode: Verify 3DNow! opcode validity

2021-01-10 18:53:32 +01:00
parent 80df5ff47c
commit 9d7b584121
2 changed files with 24 additions and 0 deletions
--- a/decode.c
+++ b/decode.c
@@ -560,6 +560,16 @@ prefix_end:
        }
    }

+    if (UNLIKELY(instr->type == FDI_3DNOW))
+    {
+        unsigned opc3dn = instr->imm;
+        if (opc3dn & 0x40)
+            return FD_ERR_UD;
+        uint64_t msk = opc3dn & 0x80 ? 0x88d144d144d14400 : 0x30003000;
+        if (!(msk >> (opc3dn & 0x3f) & 1))
+            return FD_ERR_UD;
+    }
+
    if (UNLIKELY(prefix_lock)) {
        if (!DESC_LOCK(desc) || instr->operands[0].type != FD_OT_MEM)
            return FD_ERR_UD;