lkml.org 
[lkml]   [2018]   [Mar]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/3] x86, pkeys: do not special case protection key 0
On Fri, 16 Mar 2018, Dave Hansen wrote:

>
> From: Dave Hansen <dave.hansen@linux.intel.com>
>
> mm_pkey_is_allocated() treats pkey 0 as unallocated. That is
> inconsistent with the manpages, and also inconsistent with
> mm->context.pkey_allocation_map. Stop special casing it and only
> disallow values that are actually bad (< 0).
>
> The end-user visible effect of this is that you can now use
> mprotect_pkey() to set pkey=0.
>
> This is a bit nicer than what Ram proposed because it is simpler
> and removes special-casing for pkey 0. On the other hand, it does
> allow applciations to pkey_free() pkey-0, but that's just a silly
> thing to do, so we are not going to protect against it.

What's the consequence of that? Application crashing and burning itself or
something more subtle?

Thanks,

tglx

\
 
 \ /
  Last update: 2018-03-17 10:13    [W:0.084 / U:1.356 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site