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
<...>
[<ffffffff8171f486>] skb_warn_bad_offload+0xf0/0xfd
[<ffffffff8161304c>] __skb_gso_segment+0xec/0x110
[<ffffffff8161340d>] validate_xmit_skb+0x12d/0x2b0
[<ffffffff816135d2>] validate_xmit_skb_list+0x42/0x70
[<ffffffff8163c560>] sch_direct_xmit+0xd0/0x1b0
[<ffffffff8163c760>] __qdisc_run+0x120/0x270
[<ffffffff81613b3d>] __dev_queue_xmit+0x23d/0x690
[<ffffffff81613fa0>] 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 <dcara...@redhat.com>
---
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 e978ccd4..6c319a4 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,
--
2.7.4
