Patch "Subject: [PATCH 3.14-stable] net: gso: use feature flag argument in all protocol gso handlers" has been added to the 3.14-stable tree

This is a note to let you know that I've just added the patch titled

Subject: [PATCH 3.14-stable] net: gso: use feature flag argument in all protocol gso handlers

to the 3.14-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
subject-net-gso-use-feature-flag-argument-in-all-protocol-gso-handlers.patch
and it can be found in the queue-3.14 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Florian Westphal <[email protected]>
Date: Wed, 26 Aug 2015 22:17:39 -0700
Subject: Subject: [PATCH 3.14-stable] net: gso: use feature flag argument in all protocol gso handlers

From: Florian Westphal <[email protected]>

[ Upstream commit 1e16aa3ddf863c6b9f37eddf52503230a62dedb3 ]

skb_gso_segment() has a 'features' argument representing offload features available to the output path.

A few handlers, e.g. GRE, instead re-fetch the features of skb->dev and use those instead of the provided ones when handing encapsulation/tunnels.

Depending on dev->hw_enc_features of the output device skb_gso_segment() can then return NULL even when the caller has disabled all GSO feature bits, as segmentation of inner header thinks device will take care of segmentation.

This e.g. affects the tbf scheduler, which will silently drop GRE-encap GSO skbs that did not fit the remaining token quota as the segmentation does not work when device supports corresponding hw offload capabilities.

---
 net/ipv4/af_inet.c     |    2 +-
 net/ipv4/gre_offload.c |    2 +-
 net/ipv4/udp.c         |    2 +-
 net/ipv6/ip6_offload.c |    2 +-
 net/mpls/mpls_gso.c    |    2 +-
 5 files changed, 5 insertions(+), 5 deletions(-)

@@ -1291,7 +1291,7 @@ static struct sk_buff *inet_gso_segment(
 
 	encap = SKB_GSO_CB(skb)->encap_level > 0;
 	if (encap)
-		features = skb->dev->hw_enc_features & netif_skb_features(skb);
+		features &= skb->dev->hw_enc_features;
 	SKB_GSO_CB(skb)->encap_level += ihl;
 
 	skb_reset_transport_header(skb);

@@ -69,7 +69,7 @@ static struct sk_buff *gre_gso_segment(s
 	skb->mac_len = skb_inner_network_offset(skb);
 
 	/* segment inner packet. */
-	enc_features = skb->dev->hw_enc_features & netif_skb_features(skb);
+	enc_features = skb->dev->hw_enc_features & features;
 	segs = skb_mac_gso_segment(skb, enc_features);
 	if (!segs || IS_ERR(segs)) {
 		skb_gso_error_unwind(skb, protocol, ghl, mac_offset, mac_len);

@@ -2517,7 +2517,7 @@ struct sk_buff *skb_udp_tunnel_segment(s
 	skb->protocol = htons(ETH_P_TEB);
 
 	/* segment inner packet. */
-	enc_features = skb->dev->hw_enc_features & netif_skb_features(skb);
+	enc_features = skb->dev->hw_enc_features & features;
 	segs = skb_mac_gso_segment(skb, enc_features);
 	if (!segs || IS_ERR(segs)) {
 		skb_gso_error_unwind(skb, protocol, tnl_hlen, mac_offset,

@@ -112,7 +112,7 @@ static struct sk_buff *ipv6_gso_segment(
 
 	encap = SKB_GSO_CB(skb)->encap_level > 0;
 	if (encap)
-		features = skb->dev->hw_enc_features & netif_skb_features(skb);
+		features &= skb->dev->hw_enc_features;
 	SKB_GSO_CB(skb)->encap_level += sizeof(*ipv6h);
 
 	ipv6h = ipv6_hdr(skb);

@@ -47,7 +47,7 @@ static struct sk_buff *mpls_gso_segment(
 	__skb_push(skb, skb->mac_len);
 
 	/* Segment inner packet. */
-	mpls_features = skb->dev->mpls_features & netif_skb_features(skb);
+	mpls_features = skb->dev->mpls_features & features;
 	segs = skb_mac_gso_segment(skb, mpls_features);
 
 

Patches currently in stable-queue which might be from [email protected] are

queue-3.14/subject-net-gso-use-feature-flag-argument-in-all-protocol-gso-handlers.patch queue-3.14/netlink-don-t-hold-mutex-in-rcu-callback-when-releasing-mmapd-ring.patch