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    SubjectRe: [POC][RFC][PATCH 1/2] jump_function: Addition of new feature "jump_function"
    On Mon, Oct 08, 2018 at 01:33:14AM -0700, Andy Lutomirski wrote:
    > > Can't we hijack the relocation records for these functions before they
    > > get thrown out in the (final) link pass or something?
    >
    > I could be talking out my arse here, but I thought we could do this,
    > too, then changed my mind. The relocation records give us the
    > location of the call or jump operand, but they don’t give the address
    > of the beginning of the instruction.

    But that's like 1 byte before the operand, right? We could even double check
    this by reading back that byte and ensuring it is in fact 0xE8 (CALL).

    AFAICT there is only the _1_ CALL encoding, and that is the 5 byte: E8 <PLT32>,
    so if we have the PLT32 location, we also have the instruction location. Or am
    I missing something?

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