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| author | Cong Wang <xiyou.wangcong@gmail.com> | 2017-11-07 00:47:22 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2017-11-09 04:03:09 +0300 |
| commit | ed1481681414e4d4264ad46864d5c1da5ff6ccb1 (patch) | |
| tree | 7674aba4bcb962e836a97dc7a6cced3bf06e37e8 /net/sched | |
| parent | aae2c35ec89252639a97769fa72dbbf8f1cc3107 (diff) | |
| download | linux-ed1481681414e4d4264ad46864d5c1da5ff6ccb1.tar.xz | |
cls_cgroup: use tcf_exts_get_net() before call_rcu()
Hold netns refcnt before call_rcu() and release it after
the tcf_exts_destroy() is done.
Note, on ->destroy() path we have to respect the return value
of tcf_exts_get_net(), on other paths it should always return
true, so we don't need to care.
Cc: Lucas Bates <lucasb@mojatatu.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/cls_cgroup.c | 24 |
1 files changed, 18 insertions, 6 deletions
diff --git a/net/sched/cls_cgroup.c b/net/sched/cls_cgroup.c index a97e069bee89..309d5899265f 100644 --- a/net/sched/cls_cgroup.c +++ b/net/sched/cls_cgroup.c @@ -60,15 +60,21 @@ static const struct nla_policy cgroup_policy[TCA_CGROUP_MAX + 1] = { [TCA_CGROUP_EMATCHES] = { .type = NLA_NESTED }, }; +static void __cls_cgroup_destroy(struct cls_cgroup_head *head) +{ + tcf_exts_destroy(&head->exts); + tcf_em_tree_destroy(&head->ematches); + tcf_exts_put_net(&head->exts); + kfree(head); +} + static void cls_cgroup_destroy_work(struct work_struct *work) { struct cls_cgroup_head *head = container_of(work, struct cls_cgroup_head, work); rtnl_lock(); - tcf_exts_destroy(&head->exts); - tcf_em_tree_destroy(&head->ematches); - kfree(head); + __cls_cgroup_destroy(head); rtnl_unlock(); } @@ -124,8 +130,10 @@ static int cls_cgroup_change(struct net *net, struct sk_buff *in_skb, goto errout; rcu_assign_pointer(tp->root, new); - if (head) + if (head) { + tcf_exts_get_net(&head->exts); call_rcu(&head->rcu, cls_cgroup_destroy_rcu); + } return 0; errout: tcf_exts_destroy(&new->exts); @@ -138,8 +146,12 @@ static void cls_cgroup_destroy(struct tcf_proto *tp) struct cls_cgroup_head *head = rtnl_dereference(tp->root); /* Head can still be NULL due to cls_cgroup_init(). */ - if (head) - call_rcu(&head->rcu, cls_cgroup_destroy_rcu); + if (head) { + if (tcf_exts_get_net(&head->exts)) + call_rcu(&head->rcu, cls_cgroup_destroy_rcu); + else + __cls_cgroup_destroy(head); + } } static int cls_cgroup_delete(struct tcf_proto *tp, void *arg, bool *last) |