From: Alan Cox <alan@lxorguk.ukuu.org.uk>
To: Kees Cook <keescook@chromium.org>
Cc: Oleg Nesterov <oleg@redhat.com>,
Peter Zijlstra <a.p.zijlstra@chello.nl>,
Fengguang Wu <fengguang.wu@intel.com>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: yama_ptrace_access_check(): possible recursive locking detected
Date: Wed, 15 Aug 2012 19:44:26 +0100 [thread overview]
Message-ID: <20120815194426.52fd7936@pyramind.ukuu.org.uk> (raw)
In-Reply-To: <CAGXu5jJ+HOdSxS7Ec=TW06h6KEpEmi-rF+Jk8L5LiQsp9gyAtg@mail.gmail.com>
> It sounds like get_task_comm shouldn't have locking at all then? It
> should just do a length-limited copy and make sure there is a trailing
> 0-byte?
It has locking so that it has a consistent state and more importantly it
has an accessor function
Directly accessing it is asking for bugs in future. If you hold the
needed lock then just add an
__get_task_comm()
method that asserts the lock is held. That way the rest of the behaviour
remains properly encapsulated for when someone changes it.
Alan
next prev parent reply other threads:[~2012-08-15 18:40 UTC|newest]
Thread overview: 17+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-07-26 13:47 yama_ptrace_access_check(): possible recursive locking detected Fengguang Wu
2012-07-26 15:41 ` Oleg Nesterov
2012-07-30 17:00 ` Kees Cook
2012-08-10 1:39 ` Kees Cook
2012-08-10 1:52 ` Fengguang Wu
2012-08-14 21:16 ` Kees Cook
2012-08-15 3:01 ` Fengguang Wu
2012-08-15 5:56 ` Kees Cook
2012-08-15 8:05 ` Peter Zijlstra
2012-08-15 13:01 ` Oleg Nesterov
2012-08-15 14:30 ` Peter Zijlstra
2012-08-15 17:56 ` Oleg Nesterov
2012-08-15 18:09 ` Kees Cook
2012-08-15 18:17 ` Oleg Nesterov
2012-08-15 18:30 ` Kees Cook
2012-08-15 18:44 ` Alan Cox [this message]
2012-08-15 18:43 ` Kees Cook
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