things we forget after a break in assembly coding...

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sylware

Joined: 23 Oct 2020
Posts: 462
Location: Marseille/France

sylware 01 Aug 2022, 13:07

yeah, you know that:

Code:

mov rax, 0xeeeeeeeeeeeeeeee
or [ax|al], 1

will give you 0xeeeeeeeeeeeeeeef
but

Code:

mov rax, 0xeeeeeeeeeeeeeeee
or eax, 1

will give you 0x00000000eeeeeeef

01 Aug 2022, 13:07

revolution
When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20460
Location: In your JS exploiting you and your system

revolution 01 Aug 2022, 13:13

Yeah, an easy thing to forget, that all 32-bit register writes are zero extended to 64-bits.

But all 32-bit immediates are sign extended to 64-bits.

01 Aug 2022, 13:13

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