lkml.org 
[lkml]   [2017]   [Aug]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [GIT PULL] Please pull NFS client changes for Linux 4.13
On Tue, Aug 1, 2017 at 10:20 AM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> So I think the 'pathname' part may actually be entirely a red herring,
> and it's the underlying access itself that just picks up a random
> pointer from a stack that now contains something different. And KASAN
> didn't notice the stale stack access itself, because the stack slot is
> still valid - it's just no longer the original 'verifier' allocation.
>
> Or *something* like that.

I think the "something like that" is actually just reading the
cdata->args.verifier->data pointer itself, and it *is* the stack
access - but the stack page has been free'd (because of the same fatal
signal that interrupted the rpc_wait_for_completion_task() call), and
then re-allocated (and free'd again) as a pathname page.

Maybe.

Regardless, my patch still looks conceptually correct, even if it
might have bugs due to total lack of testing.

Linus

\
 
 \ /
  Last update: 2017-08-01 19:54    [W:0.051 / U:7.548 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site