From: Davide Caratti dcaratti@redhat.com
stable inclusion from stable-5.10.51 commit 1b832bd77799dc20884ecfea06100433c82d69d3 bugzilla: 175263 https://gitee.com/openeuler/kernel/issues/I4DT6F
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...
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[ Upstream commit 05ff8435e50569a0a6b95e5ceaea43696e8827ab ]
modern userspace applications, like OVN, can configure the TC datapath to "recirculate" packets several times. If more than 4 "recirculation" rules are configured, packets can be dropped by __tcf_classify(). Changing the maximum number of reclassifications (from 4 to 16) should be sufficient to prevent drops in most use cases, and guard against loops at the same time.
Signed-off-by: Davide Caratti dcaratti@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Chen Jun chenjun102@huawei.com Acked-by: Weilong Chen chenweilong@huawei.com Signed-off-by: Chen Jun chenjun102@huawei.com --- net/sched/cls_api.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c index a281da07bb1d..30090794b791 100644 --- a/net/sched/cls_api.c +++ b/net/sched/cls_api.c @@ -1532,7 +1532,7 @@ static inline int __tcf_classify(struct sk_buff *skb, u32 *last_executed_chain) { #ifdef CONFIG_NET_CLS_ACT - const int max_reclassify_loop = 4; + const int max_reclassify_loop = 16; const struct tcf_proto *first_tp; int limit = 0;