lkml.org 
[lkml]   [2017]   [Jun]   [21]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v10 3/3] arm64/syscalls: Check address limit on user-mode return
On Wed, Jun 14, 2017 at 06:12:03PM -0700, Thomas Garnier wrote:
> Ensure the address limit is a user-mode segment before returning to
> user-mode. Otherwise a process can corrupt kernel-mode memory and
> elevate privileges [1].
>
> The set_fs function sets the TIF_SETFS flag to force a slow path on
> return. In the slow path, the address limit is checked to be USER_DS if
> needed.
>
> [1] https://bugs.chromium.org/p/project-zero/issues/detail?id=990
>
> Signed-off-by: Thomas Garnier <thgarnie@google.com>
> ---
> v10 redesigns the change to use work flags on set_fs as recommended by
> Linus and agreed by others.
>
> Based on next-20170609
> ---
> arch/arm64/include/asm/thread_info.h | 4 +++-
> arch/arm64/include/asm/uaccess.h | 3 +++
> arch/arm64/kernel/signal.c | 5 +++++
> 3 files changed, 11 insertions(+), 1 deletion(-)

For arm64:

Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>

\
 
 \ /
  Last update: 2017-06-21 10:16    [W:0.133 / U:0.364 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site