Re: [PATCH v9 06/29] x86/mpx: Use signed variables to compute effective addresses

[Borislav Petkov]

On Tue, Oct 03, 2017 at 08:54:09PM -0700, Ricardo Neri wrote:
> Even though memory addresses are unsigned, the operands used to compute the
> effective address do have a sign. This is true for ModRM.rm, SIB.base,
> SIB.index as well as the displacement bytes. Thus, signed variables shall
> be used when computing the effective address from these operands. Once the
> signed effective address has been computed, it is casted to an unsigned
> long to determine the linear address.
> 
> Variables are renamed to better reflect the type of address being
> computed.
> 
> Cc: Borislav Petkov <bp@xxxxxxx>
> Cc: Andy Lutomirski <luto@xxxxxxxxxx>
> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx>
> Cc: Adam Buchbinder <adam.buchbinder@xxxxxxxxx>
> Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx>
> Cc: Lorenzo Stoakes <lstoakes@xxxxxxxxx>
> Cc: Qiaowei Ren <qiaowei.ren@xxxxxxxxx>
> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
> Cc: Nathan Howard <liverlint@xxxxxxxxx>
> Cc: Adan Hawthorn <adanhawthorn@xxxxxxxxx>
> Cc: Joe Perches <joe@xxxxxxxxxxx>
> Cc: Ravi V. Shankar <ravi.v.shankar@xxxxxxxxx>
> Cc: x86@xxxxxxxxxx
> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@xxxxxxxxxxxxxxx>
> ---
>  arch/x86/mm/mpx.c | 20 ++++++++++++++------
>  1 file changed, 14 insertions(+), 6 deletions(-)

Reviewed-by: Borislav Petkov <bp@xxxxxxx>

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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