[PATCH 5.15.y 3/5] net: sched: use skb_ip_totlen and iph_totlen

[Sasha Levin <sashal@kernel.org>]

From: Xin Long <lucien.xin@gmail.com>

[ Upstream commit 043e397e48c58b4442ea5124dc1bdc95367a0a33 ]

There are 1 action and 1 qdisc that may process IPv4 TCP GSO packets
and access iph->tot_len, replace them with skb_ip_totlen() and
iph_totlen() accordingly.

Note that we don't need to replace the one in tcf_csum_ipv4(), as it
will return for TCP GSO packets in tcf_csum_ipv4_tcp().

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Stable-dep-of: 8a7ed561671a ("net/sched: act_ct: fix sk_buff leak when the header checks reject a packet")
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/sched/act_ct.c   | 2 +-
 net/sched/sch_cake.c | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sched/act_ct.c b/net/sched/act_ct.c
index 1639cc2869ef1..0742060400805 100644
--- a/net/sched/act_ct.c
+++ b/net/sched/act_ct.c
@@ -629,7 +629,7 @@ static int tcf_ct_skb_network_trim(struct sk_buff *skb, int family)
 
 	switch (family) {
 	case NFPROTO_IPV4:
-		len = ntohs(ip_hdr(skb)->tot_len);
+		len = skb_ip_totlen(skb);
 		break;
 	case NFPROTO_IPV6:
 		len = sizeof(struct ipv6hdr)
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index d94c9c11ac1e2..367ee57377059 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -1269,7 +1269,7 @@ static struct sk_buff *cake_ack_filter(struct cake_sched_data *q,
 			    iph_check->daddr != iph->daddr)
 				continue;
 
-			seglen = ntohs(iph_check->tot_len) -
+			seglen = iph_totlen(skb, iph_check) -
 				       (4 * iph_check->ihl);
 		} else if (iph_check->version == 6) {
 			ipv6h = (struct ipv6hdr *)iph;
-- 
2.53.0