[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Message-Id: <20090505182444.de4e0143.akpm@linux-foundation.org>
Date: Tue, 5 May 2009 18:24:44 -0700
From: Andrew Morton <akpm@...ux-foundation.org>
To: Oleg Nesterov <oleg@...hat.com>
Cc: chrisw@...s-sol.org, roland@...hat.com,
linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/3] ptrace: ptrace_attach: check PF_KTHREAD +
exit_state instead of ->mm
On Wed, 6 May 2009 01:57:36 +0200 Oleg Nesterov <oleg@...hat.com> wrote:
> On 05/05, Andrew Morton wrote:
> >
> > On Wed, 6 May 2009 00:47:22 +0200
> > Oleg Nesterov <oleg@...hat.com> wrote:
> >
> > > - Add PF_KTHREAD check to prevent attaching to the kernel thread
> > > with a borrowed ->mm.
> > >
> > > With or without this change we can race with daemonize() which
> > > can set PF_KTHREAD or clear ->mm after ptrace_attach() does the
> > > check, but this doesn't matter because reparent_to_kthreadd()
> > > does ptrace_unlink().
> > >
> > > - Kill "!task->mm" check. We don't really care about ->mm != NULL,
> > > and the task can call exit_mm() right after we drop task_lock().
> > > What we need is to make sure we can't attach after exit_notify(),
> > > check task->exit_state != 0 instead.
> > >
> >
> > These patches make a mess of utrace-core.patch. Do we really want to do that?
>
> Aaaah. Sorry! forgot to clearify...
>
> These patches depend on
>
> utrace-core-kill-exclude_xtrace-logic.patch
>
> which hopefully can be folded into utrace-core.patch. In that case these
> changes do not depend on utrace, and they can go ahead of utrace.
>
oic. Strange that the patches applied, but utrace didn't apply on them.
I now have:
#
# ptrace
#
ptrace-remove-pt_dtrace-from-arch-h8300.patch
ptrace-remove-pt_dtrace-from-avr32-mn10300-parisc-s390-sh-xtensa.patch
ptrace-remove-pt_dtrace-from-m68k-m68knommu.patch
ptrace-remove-pt_dtrace-from-arch-m32r.patch
ptrace-mm_need_new_owner-use-real_parent-to-search-in-the-siblings.patch
ptrace-tracehook_unsafe_exec-remove-the-stale-comment.patch
ptrace-tracehook_unsafe_exec-remove-the-stale-comment-fix.patch
ptrace-do-not-use-task-ptrace-directly-in-core-kernel.patch
#
# utrace
#
signals-tracehook_notify_jctl-change.patch
utrace-core.patch
utrace-core-kill-exclude_xtrace-logic.patch
#
ptrace-ptrace_attach-check-pf_kthread-exit_state-instead-of-mm.patch
ptrace-cleanup-check-set-of-pt_ptraced-during-attach.patch
ptrace-do-not-use-task_lock-for-attach.patch
ptrace_get_task_struct-s-tasklist-rcu-make-it-static.patch
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists