2023.11.15

Reptar

HN: Reptar

TLDR：采用方法fuzzing test和自创的Oracle Serialization发现了有关rep前缀的处理器bug。

这个作者的另一篇文章Zenbleed提到了几个有意思的发掘处理器bug的方法：

  • reversi: The general idea is that for every random instruction you generate, you also generate the inverse (e.g. ADD r1, r2 → SUB r1, r2).
  • Oracle: 和正确的机器/模拟器进行比较
  • Oracle Serialization（作者自创的方法）: 原指令片段和顺序化(Serialization)的指令片段比较执行结果比较，

作者有意思的自我认知：

So how come this bug wasn't found earlier? I think I did a couple of things differently, perhaps with a new perspective as I don't have an EE background.