From add641e7dee31b36aee83412c29e39dd1f5e0c9c Mon Sep 17 00:00:00 2001 From: Davide Caratti Date: Thu, 23 Mar 2017 10:39:40 +0100 Subject: [PATCH] sched: act_csum: don't mangle TCP and UDP GSO packets after act_csum computes the checksum on skbs carrying GSO TCP/UDP packets, subsequent segmentation fails because skb_needs_check(skb, true) returns true. Because of that, skb_warn_bad_offload() is invoked and the following message is displayed: WARNING: CPU: 3 PID: 28 at net/core/dev.c:2553 skb_warn_bad_offload+0xf0/0xfd <...> [] skb_warn_bad_offload+0xf0/0xfd [] __skb_gso_segment+0xec/0x110 [] validate_xmit_skb+0x12d/0x2b0 [] validate_xmit_skb_list+0x42/0x70 [] sch_direct_xmit+0xd0/0x1b0 [] __qdisc_run+0x120/0x270 [] __dev_queue_xmit+0x23d/0x690 [] dev_queue_xmit+0x10/0x20 Since GSO is able to compute checksum on individual segments of such skbs, we can simply skip mangling the packet. Signed-off-by: Davide Caratti Signed-off-by: David S. Miller --- net/sched/act_csum.c | 12 ++++++++++++ 1 file changed, 12 insertions(+) diff --git a/net/sched/act_csum.c b/net/sched/act_csum.c index e978ccd4402c..6c319a40c1cc 100644 --- a/net/sched/act_csum.c +++ b/net/sched/act_csum.c @@ -181,6 +181,9 @@ static int tcf_csum_ipv4_tcp(struct sk_buff *skb, unsigned int ihl, struct tcphdr *tcph; const struct iphdr *iph; + if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_TCPV4) + return 1; + tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph)); if (tcph == NULL) return 0; @@ -202,6 +205,9 @@ static int tcf_csum_ipv6_tcp(struct sk_buff *skb, unsigned int ihl, struct tcphdr *tcph; const struct ipv6hdr *ip6h; + if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_TCPV6) + return 1; + tcph = tcf_csum_skb_nextlayer(skb, ihl, ipl, sizeof(*tcph)); if (tcph == NULL) return 0; @@ -225,6 +231,9 @@ static int tcf_csum_ipv4_udp(struct sk_buff *skb, unsigned int ihl, const struct iphdr *iph; u16 ul; + if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) + return 1; + /* * Support both UDP and UDPLITE checksum algorithms, Don't use * udph->len to get the real length without any protocol check, @@ -278,6 +287,9 @@ static int tcf_csum_ipv6_udp(struct sk_buff *skb, unsigned int ihl, const struct ipv6hdr *ip6h; u16 ul; + if (skb_is_gso(skb) && skb_shinfo(skb)->gso_type & SKB_GSO_UDP) + return 1; + /* * Support both UDP and UDPLITE checksum algorithms, Don't use * udph->len to get the real length without any protocol check, -- 2.39.2