[PATCH 10/11] xfrm: Provide private skb extensions for segmented and hw offloaded ESP packets

[Steffen Klassert]

Commit 94579ac3f6d0 ("xfrm: Fix double ESP trailer insertion in IPsec
crypto offload.") added a XFRM_XMIT flag to avoid duplicate ESP trailer
insertion on HW offload. This flag is set on the secpath that is shared
amongst segments. This lead to a situation where some segments are
not transformed correctly when segmentation happens at layer 3.

Fix this by using private skb extensions for segmented and hw offloaded
ESP packets.

Fixes: 94579ac3f6d0 ("xfrm: Fix double ESP trailer insertion in IPsec crypto 
offload.")
Signed-off-by: Steffen Klassert <steffen.klass...@secunet.com>
---
 net/ipv4/esp4_offload.c | 11 ++++++++++-
 net/ipv6/esp6_offload.c | 11 ++++++++++-
 net/xfrm/xfrm_device.c  |  2 --
 3 files changed, 20 insertions(+), 4 deletions(-)

diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c
index ed3de486ea34..33687cf58286 100644
--- a/net/ipv4/esp4_offload.c
+++ b/net/ipv4/esp4_offload.c
@@ -314,8 +314,17 @@ static int esp_xmit(struct xfrm_state *x, struct sk_buff 
*skb,  netdev_features_
        ip_hdr(skb)->tot_len = htons(skb->len);
        ip_send_check(ip_hdr(skb));
 
-       if (hw_offload)
+       if (hw_offload) {
+               if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
+                       return -ENOMEM;
+
+               xo = xfrm_offload(skb);
+               if (!xo)
+                       return -EINVAL;
+
+               xo->flags |= XFRM_XMIT;
                return 0;
+       }
 
        err = esp_output_tail(x, skb, &esp);
        if (err)
diff --git a/net/ipv6/esp6_offload.c b/net/ipv6/esp6_offload.c
index f35203ab39f5..4af56affaafd 100644
--- a/net/ipv6/esp6_offload.c
+++ b/net/ipv6/esp6_offload.c
@@ -348,8 +348,17 @@ static int esp6_xmit(struct xfrm_state *x, struct sk_buff 
*skb,  netdev_features
 
        ipv6_hdr(skb)->payload_len = htons(len);
 
-       if (hw_offload)
+       if (hw_offload) {
+               if (!skb_ext_add(skb, SKB_EXT_SEC_PATH))
+                       return -ENOMEM;
+
+               xo = xfrm_offload(skb);
+               if (!xo)
+                       return -EINVAL;
+
+               xo->flags |= XFRM_XMIT;
                return 0;
+       }
 
        err = esp6_output_tail(x, skb, &esp);
        if (err)
diff --git a/net/xfrm/xfrm_device.c b/net/xfrm/xfrm_device.c
index edf11893dbe8..6d6917b68856 100644
--- a/net/xfrm/xfrm_device.c
+++ b/net/xfrm/xfrm_device.c
@@ -134,8 +134,6 @@ struct sk_buff *validate_xmit_xfrm(struct sk_buff *skb, 
netdev_features_t featur
                return skb;
        }
 
-       xo->flags |= XFRM_XMIT;
-
        if (skb_is_gso(skb) && unlikely(x->xso.dev != dev)) {
                struct sk_buff *segs;
 
-- 
2.25.1