6.6-stable review patch. If anyone has any objections, please let me know.
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From: Eric Dumazet edumazet@google.com
[ Upstream commit d300335b4e18672913dd792ff9f49e6cccf41d26 ]
Commit 21c167aa0ba9 ("net/sched: act_ctinfo: use percpu stats") missed that stats_dscp_set, stats_dscp_error and stats_cpmark_set might be written (and read) locklessly.
Use atomic64_t for these three fields, I doubt act_ctinfo is used heavily on big SMP hosts anyway.
Fixes: 24ec483cec98 ("net: sched: Introduce act_ctinfo action") Signed-off-by: Eric Dumazet edumazet@google.com Cc: Pedro Tammela pctammela@mojatatu.com Link: https://patch.msgid.link/20250709090204.797558-6-edumazet@google.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/net/tc_act/tc_ctinfo.h | 6 +++--- net/sched/act_ctinfo.c | 19 +++++++++++-------- 2 files changed, 14 insertions(+), 11 deletions(-)
diff --git a/include/net/tc_act/tc_ctinfo.h b/include/net/tc_act/tc_ctinfo.h index f071c1d70a25..a04bcac7adf4 100644 --- a/include/net/tc_act/tc_ctinfo.h +++ b/include/net/tc_act/tc_ctinfo.h @@ -18,9 +18,9 @@ struct tcf_ctinfo_params { struct tcf_ctinfo { struct tc_action common; struct tcf_ctinfo_params __rcu *params; - u64 stats_dscp_set; - u64 stats_dscp_error; - u64 stats_cpmark_set; + atomic64_t stats_dscp_set; + atomic64_t stats_dscp_error; + atomic64_t stats_cpmark_set; };
enum { diff --git a/net/sched/act_ctinfo.c b/net/sched/act_ctinfo.c index 4d15b6a6169c..8792244620b9 100644 --- a/net/sched/act_ctinfo.c +++ b/net/sched/act_ctinfo.c @@ -44,9 +44,9 @@ static void tcf_ctinfo_dscp_set(struct nf_conn *ct, struct tcf_ctinfo *ca, ipv4_change_dsfield(ip_hdr(skb), INET_ECN_MASK, newdscp); - ca->stats_dscp_set++; + atomic64_inc(&ca->stats_dscp_set); } else { - ca->stats_dscp_error++; + atomic64_inc(&ca->stats_dscp_error); } } break; @@ -57,9 +57,9 @@ static void tcf_ctinfo_dscp_set(struct nf_conn *ct, struct tcf_ctinfo *ca, ipv6_change_dsfield(ipv6_hdr(skb), INET_ECN_MASK, newdscp); - ca->stats_dscp_set++; + atomic64_inc(&ca->stats_dscp_set); } else { - ca->stats_dscp_error++; + atomic64_inc(&ca->stats_dscp_error); } } break; @@ -72,7 +72,7 @@ static void tcf_ctinfo_cpmark_set(struct nf_conn *ct, struct tcf_ctinfo *ca, struct tcf_ctinfo_params *cp, struct sk_buff *skb) { - ca->stats_cpmark_set++; + atomic64_inc(&ca->stats_cpmark_set); skb->mark = READ_ONCE(ct->mark) & cp->cpmarkmask; }
@@ -323,15 +323,18 @@ static int tcf_ctinfo_dump(struct sk_buff *skb, struct tc_action *a, }
if (nla_put_u64_64bit(skb, TCA_CTINFO_STATS_DSCP_SET, - ci->stats_dscp_set, TCA_CTINFO_PAD)) + atomic64_read(&ci->stats_dscp_set), + TCA_CTINFO_PAD)) goto nla_put_failure;
if (nla_put_u64_64bit(skb, TCA_CTINFO_STATS_DSCP_ERROR, - ci->stats_dscp_error, TCA_CTINFO_PAD)) + atomic64_read(&ci->stats_dscp_error), + TCA_CTINFO_PAD)) goto nla_put_failure;
if (nla_put_u64_64bit(skb, TCA_CTINFO_STATS_CPMARK_SET, - ci->stats_cpmark_set, TCA_CTINFO_PAD)) + atomic64_read(&ci->stats_cpmark_set), + TCA_CTINFO_PAD)) goto nla_put_failure;
spin_unlock_bh(&ci->tcf_lock);