From: Oleg Nesterov <oleg@redhat.com>
To: Tejun Heo <tj@kernel.org>
Cc: linux-kernel@vger.kernel.org, akpm@linux-foundation.org,
torvalds@linux-foundation.org, hch@infradead.org,
John Johansen <john.johansen@canonical.com>,
Stephen Smalley <sds@tycho.nsa.gov>
Subject: Re: [PATCH 7/7] ptrace: s/tracehook_tracer_task()/ptrace_parent()/
Date: Mon, 20 Jun 2011 22:16:03 +0200 [thread overview]
Message-ID: <20110620201603.GA17157@redhat.com> (raw)
In-Reply-To: <1308322240-8247-8-git-send-email-tj@kernel.org>
On 06/17, Tejun Heo wrote:
>
> tracehook.h is on the way out. Rename tracehook_tracer_task() to
> ptrace_parent() and move it from tracehook.h to ptrace.h.
I am a bit surpised you decided to keep this helper. Can't we simply
kill it?
OK, we will see. I guess this change is mostly needed to remove yet
another function from tracehook.h.
> @@ -216,7 +216,7 @@ static struct mm_struct *__check_mem_permission(struct task_struct *task)
> if (task_is_stopped_or_traced(task)) {
> int match;
> rcu_read_lock();
> - match = (tracehook_tracer_task(task) == current);
> + match = (ptrace_parent(task) == current);
> rcu_read_unlock();
> if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
All we need
if (task_is_traced(task) && task->parent == current) {
if (ptrace_may_access()
return mm;
}
Of course I do not blame this patch, my only point is that this helper
only adds more confusion imho.
> @@ -67,7 +67,7 @@ static int may_change_ptraced_domain(struct task_struct *task,
> int error = 0;
>
> rcu_read_lock();
> - tracer = tracehook_tracer_task(task);
> + tracer = ptrace_parent(task);
> if (tracer) {
> /* released below */
> cred = get_task_cred(tracer);
Hmm. And then this task_struct is used after we dropped rcu_read_lock().
John, is this correct?
Oleg.
next prev parent reply other threads:[~2011-06-20 20:18 UTC|newest]
Thread overview: 44+ messages / expand[flat|nested] mbox.gz Atom feed top
2011-06-17 14:50 [PATCHSET] ptrace: kill most tracehooks Tejun Heo
2011-06-17 14:50 ` [PATCH 1/7] ptrace: kill task_ptrace() Tejun Heo
2011-06-17 14:50 ` [PATCH 2/7] ptrace: introduce ptrace_event_enabled() and simplify ptrace_event() and tracehook_prepare_clone() Tejun Heo
2011-06-17 14:50 ` [PATCH 3/7] ptrace: move SIGTRAP on exec(2) logic to ptrace_event() Tejun Heo
2011-06-20 20:25 ` Oleg Nesterov
2011-06-21 7:21 ` Tejun Heo
2011-06-21 20:40 ` Oleg Nesterov
2011-06-23 8:58 ` Tejun Heo
2011-06-17 14:50 ` [PATCH 4/7] ptrace: kill trivial tracehooks Tejun Heo
2011-06-17 14:50 ` [PATCH 5/7] ptrace: kill clone/exec tracehooks Tejun Heo
2011-06-20 20:33 ` Oleg Nesterov
2011-06-21 7:24 ` Tejun Heo
2011-06-17 14:50 ` [PATCH 6/7] ptrace: kill detah tracehooks Tejun Heo
2011-06-20 19:39 ` Oleg Nesterov
2011-06-21 20:23 ` Oleg Nesterov
2011-06-23 9:24 ` Tejun Heo
2011-06-22 21:07 ` [PATCH 0/8] kill task_detached() (Was: ptrace: kill detah tracehooks) Oleg Nesterov
2011-06-22 21:08 ` [PATCH 1/8] make do_notify_parent() return bool Oleg Nesterov
2011-06-23 9:52 ` Tejun Heo
2011-06-22 21:08 ` [PATCH 2/8] kill tracehook_notify_death() Oleg Nesterov
2011-06-23 12:22 ` Tejun Heo
2011-06-23 13:21 ` Oleg Nesterov
2011-06-23 13:27 ` Tejun Heo
2011-06-23 13:28 ` Oleg Nesterov
2011-06-23 17:06 ` Oleg Nesterov
2011-06-25 14:15 ` Tejun Heo
2011-06-26 20:51 ` Oleg Nesterov
2011-06-27 8:24 ` Tejun Heo
2011-06-27 14:21 ` Oleg Nesterov
2011-06-27 14:36 ` Tejun Heo
2011-06-22 21:08 ` [PATCH 3/8] __ptrace_detach: avoid task_detached(), check do_notify_parent() Oleg Nesterov
2011-06-23 13:25 ` Tejun Heo
2011-06-22 21:09 ` [PATCH 4/8] make do_notify_parent() __must_check, update the callers Oleg Nesterov
2011-06-23 13:38 ` Tejun Heo
2011-06-22 21:09 ` [PATCH 5/8] reparent_leader: check EXIT_DEAD instead of task_detached() Oleg Nesterov
2011-06-22 21:09 ` [PATCH 6/8] kill task_detached() Oleg Nesterov
2011-06-22 21:10 ` [PATCH 7/8] do not change dead_task->exit_signal Oleg Nesterov
2011-06-22 21:10 ` [PATCH 8/8] redefine thread_group_leader() as exit_signal >= 0 Oleg Nesterov
2011-06-23 13:56 ` Tejun Heo
2011-06-17 14:50 ` [PATCH 7/7] ptrace: s/tracehook_tracer_task()/ptrace_parent()/ Tejun Heo
2011-06-20 20:16 ` Oleg Nesterov [this message]
2011-06-21 11:44 ` John Johansen
2011-06-23 9:14 ` Tejun Heo
2011-06-20 11:16 ` [PATCHSET] ptrace: kill most tracehooks Christoph Hellwig
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