lkml.org 
[lkml]   [2011]   [Sep]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH resend] user namespace: usb: make usb urbs user namespace aware (v2)
Quoting Alan Stern (stern@rowland.harvard.edu):
> On Fri, 23 Sep 2011, Serge E. Hallyn wrote:
>
> > Quoting Alan Stern (stern@rowland.harvard.edu):
> > > On Fri, 23 Sep 2011, Serge E. Hallyn wrote:
> > >
> > > > (re-sending to Cc: Greg and linux-usb)
> > > >
> > > > Add to the dev_state and alloc_async structures the user namespace
> > > > corresponding to the uid and euid. Pass these to kill_pid_info_as_uid(),
> > > > which can then implement a proper, user-namespace-aware uid check.
> > > >
> > > > Changelog:
> > > > Sep 20: Per Oleg's suggestion: Instead of caching and passing user namespace,
> > > > uid, and euid each separately, pass a struct cred.
> > >
> > > This should be broken up into two separate patches: One to add
> > > kill_pid_info_as_cred() and the other to modify the usbfs driver.
> >
> > It seems like that would make the first patch harder to review (since
> > it won't just show the changes from kill_pid_info_as_uid to
> > kill_pid_info_as_cred), but I'll go ahead and split it up. I assume
> > kill_pid_info_as_uid should be removed in a third patch?
>
> No, what I meant was that all the changes to /kernel/signal.c should be
> in one patch and all the changes to drivers/usb/core/devio.c should be
> in a second patch.

But doing that in two patches would not be bisect-safe.

> You did check to make sure there are no other references to
> kill_pid_info_as_uid() in the kernel?

Yup.

> > > > if (signr)
> > > > - kill_pid_info_as_uid(sinfo.si_signo, &sinfo, pid, uid,
> > > > - euid, secid);
> > > > + kill_pid_info_as_cred(sinfo.si_signo, &sinfo, pid, cred, secid);
> > >
> > > This continues a bug that already exists in the current code. Once
> > > ps->lock is released, there is no guarantee that the async structure
> > > will still exist. It may already have been freed, and the reference to
> >
> > Yikes. That makes sense. I'll fix that for the cred and the pid as well
> > then?
>
> Right.

Ok.

thanks,
-serge


\
 
 \ /
  Last update: 2011-09-23 19:25    [W:0.206 / U:0.068 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site