lkml.org 
[lkml]   [2018]   [Mar]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 3.18 17/68] sched: act_csum: dont mangle TCP and UDP GSO packets
Date
3.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Davide Caratti <dcaratti@redhat.com>


[ Upstream commit add641e7dee31b36aee83412c29e39dd1f5e0c9c ]

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 <dcaratti@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
net/sched/act_csum.c | 12 ++++++++++++
1 file changed, 12 insertions(+)

--- a/net/sched/act_csum.c
+++ b/net/sched/act_csum.c
@@ -176,6 +176,9 @@ static int tcf_csum_ipv4_tcp(struct sk_b
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;
@@ -197,6 +200,9 @@ static int tcf_csum_ipv6_tcp(struct sk_b
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;
@@ -220,6 +226,9 @@ static int tcf_csum_ipv4_udp(struct sk_b
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,
@@ -273,6 +282,9 @@ static int tcf_csum_ipv6_udp(struct sk_b
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,

\
 
 \ /
  Last update: 2018-03-19 21:51    [W:0.251 / U:1.752 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site