Re: [PATCH v5 05/20] x86/decompressor: Use proper sequence to take the address of the GOT

[Borislav Petkov]

On Fri, Jun 23, 2023 at 04:00:30PM +0200, Ard Biesheuvel wrote:
> if you assemble this
> 
> movl $_GLOBAL_OFFSET_TABLE_, %eax
> movl $_GLOBAL_OFFSET_TABLE, %eax
> 
> you'll end up with
> 
>    0: b8 01 00 00 00        mov    $0x1,%eax
> 1: R_386_GOTPC _GLOBAL_OFFSET_TABLE_
>    5: b8 00 00 00 00        mov    $0x0,%eax
> 6: R_386_32 _GLOBAL_OFFSET_TABLE
> 
> So it is not possible to take the absolute address of
> _GLOBAL_OFFSET_TABLE_ via an absolute relocation, you will always get
> the relative offset instead.

Right.

Thx.

-- 
Regards/Gruss,
    Boris.

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