lkml.org 
[lkml]   [2021]   [Jul]   [5]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v2] selftests/sgx: Fix Q1 and Q2 calculation in sigstruct.c
On Mon, Jul 05, 2021 at 08:09:21AM +0300, Jarkko Sakkinen wrote:
> From: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
>
> Q1 and Q2 are numbers with *maximum* length of 384 bytes. If the calculated
> length of Q1 and Q2 is less than 384 bytes, things will go wrong.
>
> E.g. if Q2 is 383 bytes, then
>
> 1. The bytes of q2 are copied to sigstruct->q2 in calc_q1q2().
> 2. The entire sigstruct->q2 is reversed, which results it being
> 256 * Q2, given that the last byte of sigstruct->q2 is added
> to before the bytes given by calc_q1q2().
>
> Either change in key or measurement can trigger the bug. E.g. an unmeasured
> heap could cause a devastating change in Q1 or Q2.
>
> Reverse exactly the bytes of Q1 and Q2 in calc_q1q2() before returning to
> the caller.
>
> Fixes: dedde2634570 ("selftests/sgx: Trigger the reclaimer in the selftests")

Oops :-(

Was meant to be

Fixes: 2adcba79e69d ("selftests/x86: Add a selftest for SGX")

/Jarkko

\
 
 \ /
  Last update: 2021-07-05 07:11    [W:0.096 / U:0.024 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site