From: Johannes Weiner <hannes@cmpxchg.org>
To: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>,
cgroups@vger.kernel.org, linux-kernel@vger.kernel.org,
kernel-team@fb.com
Subject: Re: [PATCH cgroup/for-4.8] cgroup: allow NULL return from ss->css_alloc()
Date: Tue, 21 Jun 2016 14:14:04 -0400 [thread overview]
Message-ID: <20160621181404.GB4501@cmpxchg.org> (raw)
In-Reply-To: <20160621170624.GK3262@mtj.duckdns.org>
On Tue, Jun 21, 2016 at 01:06:24PM -0400, Tejun Heo wrote:
> cgroup core expected css_alloc to return an ERR_PTR value on failure
> and caused NULL deref if it returned NULL. It's an easy mistake to
> make from an alloc function and there's no ambiguity in what's being
> indicated. Update css_create() so that it interprets NULL return from
> css_alloc as -ENOMEM.
>
> Signed-off-by: Tejun Heo <tj@kernel.org>
Would it be better to remove the error code instead and have everybody
return NULL? AFAICS, everybody is returning either the object or the
-ENOMEM error code right now.
What error condition is there for an allocation function?
next prev parent reply other threads:[~2016-06-21 18:18 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-06-21 17:06 [PATCH cgroup/for-4.8] cgroup: allow NULL return from ss->css_alloc() Tejun Heo
2016-06-21 18:14 ` Johannes Weiner [this message]
2016-06-21 18:57 ` Tejun Heo
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