From: Jiri Pirko <jiri@resnulli.us>
To: Vlad Buslov <vladbu@mellanox.com>
Cc: netdev@vger.kernel.org, davem@davemloft.net, jhs@mojatatu.com,
xiyou.wangcong@gmail.com, pablo@netfilter.org,
kadlec@blackhole.kfki.hu, fw@strlen.de, ast@kernel.org,
daniel@iogearbox.net, edumazet@google.com, keescook@chromium.org,
linux-kernel@vger.kernel.org, netfilter-devel@vger.kernel.org,
coreteam@netfilter.org, kliteyn@mellanox.com
Subject: Re: [PATCH 09/14] net: sched: don't release reference on action overwrite
Date: Wed, 16 May 2018 09:50:29 +0200 [thread overview]
Message-ID: <20180516075029.GD1972@nanopsycho> (raw)
In-Reply-To: <vbfd0xw11pn.fsf@reg-r-vrt-018-180.mtr.labs.mlnx>
Wed, May 16, 2018 at 09:47:32AM CEST, vladbu@mellanox.com wrote:
>
>On Wed 16 May 2018 at 07:43, Jiri Pirko <jiri@resnulli.us> wrote:
>> Mon, May 14, 2018 at 04:27:10PM CEST, vladbu@mellanox.com wrote:
>>>Return from action init function with reference to action taken,
>>>even when overwriting existing action.
>>>
>>>Action init API initializes its fourth argument (pointer to pointer to
>>>tc action) to either existing action with same index or newly created
>>>action. In case of existing index(and bind argument is zero), init
>>>function returns without incrementing action reference counter. Caller
>>>of action init then proceeds working with action without actually
>>>holding reference to it. This means that action could be deleted
>>>concurrently. To prevent such scenario this patch changes action init
>>
>> Be imperative to the codebase in the patch description.
>>
>>
>>>behavior to always take reference to action before returning
>>>successfully.
>>
>> Where's the balance? Who does the release instead? I'm probably missing
>> something.
>
>I've resplit these patches for V2 to always do take/release in same
>patch.
Good. Thanks.
>
>>
>>>
>>>Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
>>>---
>>> net/sched/act_bpf.c | 8 ++++----
>>> net/sched/act_connmark.c | 5 +++--
>>> net/sched/act_csum.c | 8 ++++----
>>> net/sched/act_gact.c | 5 +++--
>>> net/sched/act_ife.c | 12 +++++-------
>>> net/sched/act_ipt.c | 5 +++--
>>> net/sched/act_mirred.c | 5 ++---
>>> net/sched/act_nat.c | 5 +++--
>>> net/sched/act_pedit.c | 5 +++--
>>> net/sched/act_police.c | 8 +++-----
>>> net/sched/act_sample.c | 8 +++-----
>>> net/sched/act_simple.c | 5 +++--
>>> net/sched/act_skbedit.c | 5 +++--
>>> net/sched/act_skbmod.c | 8 +++-----
>>> net/sched/act_tunnel_key.c | 8 +++-----
>>> net/sched/act_vlan.c | 8 +++-----
>>> 16 files changed, 51 insertions(+), 57 deletions(-)
>>>
>>>diff --git a/net/sched/act_bpf.c b/net/sched/act_bpf.c
>>>index 5d95c43..5554bf7 100644
>>>--- a/net/sched/act_bpf.c
>>>+++ b/net/sched/act_bpf.c
>>>@@ -311,9 +311,10 @@ static int tcf_bpf_init(struct net *net, struct nlattr *nla,
>>> if (bind)
>>> return 0;
>>>
>>>- tcf_idr_release(*act, bind);
>>>- if (!replace)
>>>+ if (!replace) {
>>>+ tcf_idr_release(*act, bind);
>>> return -EEXIST;
>>>+ }
>>> }
>>>
>>> is_bpf = tb[TCA_ACT_BPF_OPS_LEN] && tb[TCA_ACT_BPF_OPS];
>>
>> [...]
>
next prev parent reply other threads:[~2018-05-16 7:50 UTC|newest]
Thread overview: 86+ messages / expand[flat|nested] mbox.gz Atom feed top
2018-05-14 14:27 [PATCH 00/14] Modify action API for implementing lockless actions Vlad Buslov
2018-05-14 14:27 ` [PATCH 01/14] net: sched: use rcu for action cookie update Vlad Buslov
2018-05-14 15:10 ` Jiri Pirko
2018-05-14 23:39 ` kbuild test robot
2018-05-14 14:27 ` [PATCH 02/14] net: sched: change type of reference and bind counters Vlad Buslov
2018-05-14 15:11 ` Jiri Pirko
2018-05-19 21:04 ` Marcelo Ricardo Leitner
2018-05-20 10:55 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 03/14] net: sched: add 'delete' function to action ops Vlad Buslov
2018-05-14 15:12 ` Jiri Pirko
2018-05-14 16:30 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 04/14] net: sched: implement unlocked action init API Vlad Buslov
2018-05-14 15:16 ` Jiri Pirko
2018-05-19 21:11 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 05/14] net: sched: always take reference to action Vlad Buslov
2018-05-14 16:23 ` Jiri Pirko
2018-05-14 18:49 ` Vlad Buslov
2018-05-15 8:58 ` Jiri Pirko
2018-05-15 11:52 ` Vlad Buslov
2018-05-15 1:38 ` kbuild test robot
2018-05-15 1:38 ` [RFC PATCH] net: sched: __tcf_idr_check() can be static kbuild test robot
2018-05-14 14:27 ` [PATCH 06/14] net: sched: implement reference counted action release Vlad Buslov
2018-05-14 16:28 ` Jiri Pirko
2018-05-14 16:47 ` Jiri Pirko
2018-05-14 19:07 ` Vlad Buslov
2018-05-15 9:03 ` Jiri Pirko
2018-05-15 9:16 ` Vlad Buslov
2018-05-19 21:43 ` Marcelo Ricardo Leitner
2018-05-20 6:22 ` Jiri Pirko
2018-05-20 10:59 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 07/14] net: sched: use reference counting action init Vlad Buslov
2018-05-15 11:24 ` Jiri Pirko
2018-05-15 11:32 ` Vlad Buslov
2018-05-15 11:39 ` Jiri Pirko
2018-05-15 11:41 ` Vlad Buslov
2018-05-15 11:57 ` Jiri Pirko
2018-05-15 12:00 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 08/14] net: sched: account for temporary action reference Vlad Buslov
2018-05-16 7:12 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 09/14] net: sched: don't release reference on action overwrite Vlad Buslov
2018-05-16 7:43 ` Jiri Pirko
2018-05-16 7:47 ` Vlad Buslov
2018-05-16 7:50 ` Jiri Pirko [this message]
2018-05-19 21:52 ` Marcelo Ricardo Leitner
2018-05-20 18:42 ` Vlad Buslov
2018-05-14 14:27 ` [PATCH 10/14] net: sched: extend act API for lockless actions Vlad Buslov
2018-05-16 7:50 ` Jiri Pirko
2018-05-16 8:16 ` Vlad Buslov
2018-05-16 8:56 ` Jiri Pirko
2018-05-16 9:39 ` Vlad Buslov
2018-05-19 22:17 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 11/14] net: core: add new/replace rate estimator lock parameter Vlad Buslov
2018-05-16 9:54 ` Jiri Pirko
2018-05-16 10:00 ` Vlad Buslov
2018-05-16 10:11 ` Jiri Pirko
2018-05-14 14:27 ` [PATCH 12/14] net: sched: retry action check-insert on concurrent modification Vlad Buslov
2018-05-16 9:59 ` Jiri Pirko
2018-05-16 11:55 ` Vlad Buslov
2018-05-16 12:26 ` Jiri Pirko
2018-05-16 12:43 ` Vlad Buslov
2018-05-16 13:21 ` Jiri Pirko
2018-05-16 13:52 ` Vlad Buslov
2018-05-16 14:13 ` Jiri Pirko
2018-05-16 14:26 ` Vlad Buslov
2018-05-16 14:55 ` Jiri Pirko
2018-05-19 22:35 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 13/14] net: sched: use unique idr insert function in unlocked actions Vlad Buslov
2018-05-16 9:50 ` Jiri Pirko
2018-05-16 9:54 ` Vlad Buslov
2018-05-19 22:20 ` Marcelo Ricardo Leitner
2018-05-20 21:13 ` Or Gerlitz
2018-05-20 21:33 ` Marcelo Ricardo Leitner
2018-05-20 21:40 ` Or Gerlitz
2018-05-20 22:43 ` Marcelo Ricardo Leitner
2018-05-14 14:27 ` [PATCH 14/14] net: sched: implement delete for all actions Vlad Buslov
2018-05-16 9:48 ` Jiri Pirko
2018-05-16 9:58 ` Vlad Buslov
2018-05-19 22:45 ` Marcelo Ricardo Leitner
2018-05-14 18:03 ` [PATCH 00/14] Modify action API for implementing lockless actions Jamal Hadi Salim
2018-05-14 20:46 ` Vlad Buslov
2018-05-15 18:25 ` Jamal Hadi Salim
2018-05-15 21:21 ` Vlad Buslov
2018-05-15 8:20 ` Jiri Pirko
2018-05-24 23:34 ` Cong Wang
2018-05-25 20:39 ` Vlad Buslov
2018-05-25 21:40 ` Cong Wang
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