lkml.org 
[lkml]   [2018]   [Dec]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Subject[PATCH v2 0/2] uaccess: Add unsafe accessors for arm64
Date
Hi,

First version of this series[1] was briefly in linux-next but had to be
reverted due to a bug where schedule would end up being called while
user_access was active[2].

After clarifications[3], rescheduling while in a user_access region is not
allowed.

* Patch 1 clarifies this restriction in the API and attempts to check
against violations of the restriction.
* Patch 2 implements the unsafe accessors for arm64

Changes since v1:
- Add a way to detect code calling schedule within a user_access region
- Make sure put_user/get_user arguments are evaluated before disabling PAN

[1] https://www.spinics.net/lists/arm-kernel/msg674925.html
[2] https://patchwork.kernel.org/patch/10634783/
[3] https://lkml.org/lkml/2018/11/28/50

Cheers,

Julien

-->

Julien Thierry (2):
uaccess: Check no rescheduling function is called in unsafe region
arm64: uaccess: Implement unsafe accessors

arch/arm64/include/asm/sysreg.h | 2 +
arch/arm64/include/asm/uaccess.h | 89 +++++++++++++++++++++++++++++++---------
include/linux/kernel.h | 6 ++-
include/linux/uaccess.h | 11 +++++
kernel/sched/core.c | 19 +++++++++
5 files changed, 105 insertions(+), 22 deletions(-)

--
1.9.1

\
 
 \ /
  Last update: 2018-12-03 14:56    [W:0.093 / U:4.564 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site