size_t-to-int vulnerability in Linux’s filesystem layer

Re:size_t-to-int vulnerability in Linux’s filesystem layer by mgraczyk on Tuesday July 20, 2021 @02:59PM (#27897745)

The Ethereum virtual machine addresses it's storage with 256 bits, so there's one wild example. Although in this case you'd probably not want to use usize directly to represent storage.

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Re:size_t-to-int vulnerability in Linux’s filesystem layer by eloff on Tuesday July 20, 2021 @03:09PM (#27897890)

I'm not familiar with the Ethereum virtual machine, are these really memory pointers? Surely it's represented differently?

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Re:size_t-to-int vulnerability in Linux’s filesystem layer by mgraczyk on Tuesday July 20, 2021 @03:59PM (#27898501)

EVM is a stack machine, and it has durable storage which is addressed using 256 bit "pointers". So you can do something like

    push x // 256 bit constant
    LOAD
    // top of stack now contains storage[x]

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