5.4-stable review patch. If anyone has any objections, please let me know.
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From: Vlad Buslov vladbu@mellanox.com
[ Upstream commit ef816f3c49c1c404ababc50e10d4cbe5109da678 ]
Previous commit introduced helper function for updating qstats and refactored set of actions to use the helpers, instead of modifying qstats directly. However, one of the affected action exposes its qstats to skb_tc_reinsert(), which then modifies it.
Refactor skb_tc_reinsert() to return integer error code and don't increment overlimit qstats in case of error, and use the returned error code in tcf_mirred_act() to manually increment the overlimit counter with new helper function.
Signed-off-by: Vlad Buslov vladbu@mellanox.com Acked-by: Jiri Pirko jiri@mellanox.com Signed-off-by: David S. Miller davem@davemloft.net [ skulkarni: Adjusted patch for file 'sch_generic.h' wrt the mainline commit ] Stable-dep-of: ca22da2fbd69 ("act_mirred: use the backlog for nested calls to mirred ingress") Signed-off-by: Shubham Kulkarni skulkarni@mvista.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/net/sch_generic.h | 12 ++---------- net/sched/act_mirred.c | 4 ++-- 2 files changed, 4 insertions(+), 12 deletions(-)
--- a/include/net/sch_generic.h +++ b/include/net/sch_generic.h @@ -1320,17 +1320,9 @@ void mini_qdisc_pair_swap(struct mini_Qd void mini_qdisc_pair_init(struct mini_Qdisc_pair *miniqp, struct Qdisc *qdisc, struct mini_Qdisc __rcu **p_miniq);
-static inline void skb_tc_reinsert(struct sk_buff *skb, struct tcf_result *res) +static inline int skb_tc_reinsert(struct sk_buff *skb, struct tcf_result *res) { - struct gnet_stats_queue *stats = res->qstats; - int ret; - - if (res->ingress) - ret = netif_receive_skb(skb); - else - ret = dev_queue_xmit(skb); - if (ret && stats) - qstats_overlimit_inc(res->qstats); + return res->ingress ? netif_receive_skb(skb) : dev_queue_xmit(skb); }
/* Make sure qdisc is no longer in SCHED state. */ --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -295,8 +295,8 @@ static int tcf_mirred_act(struct sk_buff /* let's the caller reinsert the packet, if possible */ if (use_reinsert) { res->ingress = want_ingress; - res->qstats = this_cpu_ptr(m->common.cpu_qstats); - skb_tc_reinsert(skb, res); + if (skb_tc_reinsert(skb, res)) + tcf_action_inc_overlimit_qstats(&m->common); __this_cpu_dec(mirred_rec_level); return TC_ACT_CONSUMED; }