[PATCH net-next] Revert "ipv6: Initial skb->dev and skb->protocol in ip6_output"

[PATCH net-next] Revert "ipv6: Initial skb->dev and skb->protocol in ip6_output"

[Chenbo Feng]

From: Chenbo Feng <fengc@google.com>

This reverts commit 97a7a37a7b7b("ipv6: Initial skb->dev and
skb->protocol in ip6_output") since it does not handles the
skb->dev assignment inside ip6_fragment() code path properly.
Need to rework and upload again

Fixes: 97a7a37a7b7b("ipv6: Initial skb->dev and skb->protocol in ip6_output")
Signed-off-by: Chenbo Feng <fengc@google.com>
---
 net/ipv6/ip6_output.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 02cd44f..bf8a58a 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -67,6 +67,9 @@ static int ip6_finish_output2(struct net *net, struct sock *sk, struct sk_buff *
 	struct in6_addr *nexthop;
 	int ret;
 
+	skb->protocol = htons(ETH_P_IPV6);
+	skb->dev = dev;
+
 	if (ipv6_addr_is_multicast(&ipv6_hdr(skb)->daddr)) {
 		struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 
@@ -151,9 +154,6 @@ int ip6_output(struct net *net, struct sock *sk, struct sk_buff *skb)
 	struct net_device *dev = skb_dst(skb)->dev;
 	struct inet6_dev *idev = ip6_dst_idev(skb_dst(skb));
 
-	skb->protocol = htons(ETH_P_IPV6);
-	skb->dev = dev;
-
 	if (unlikely(idev->cnf.disable_ipv6)) {
 		IP6_INC_STATS(net, idev, IPSTATS_MIB_OUTDISCARDS);
 		kfree_skb(skb);
-- 
2.7.4

Re: [PATCH net-next] Revert "ipv6: Initial skb->dev and skb->protocol in ip6_output"

[Eric Dumazet]

On Fri, 2017-06-09 at 12:56 -0700, Chenbo Feng wrote:
> From: Chenbo Feng <fengc@google.com>
> 
> This reverts commit 97a7a37a7b7b("ipv6: Initial skb->dev and
> skb->protocol in ip6_output") since it does not handles the
> skb->dev assignment inside ip6_fragment() code path properly.
> Need to rework and upload again

We can avoid the revert I believe the patch is fine after analysis.

Please submit this followup, thanks ! :

diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
index 02cd44f0953900108701895108b2fdaa9f9980e5..0d6f3b6345de26c329ae1d6f25dde652a5452d4b 100644
--- a/net/ipv6/ip6_output.c
+++ b/net/ipv6/ip6_output.c
@@ -869,7 +869,6 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
 	if (skb->sk && dst_allfrag(skb_dst(skb)))
 		sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
 
-	skb->dev = skb_dst(skb)->dev;
 	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
 	err = -EMSGSIZE;
 

Re: [PATCH net-next] Revert "ipv6: Initial skb->dev and skb->protocol in ip6_output"

[Chenbo Feng]

On 06/10/2017 07:55 AM, Eric Dumazet wrote:
> On Fri, 2017-06-09 at 12:56 -0700, Chenbo Feng wrote:
>> From: Chenbo Feng <fengc@google.com>
>>
>> This reverts commit 97a7a37a7b7b("ipv6: Initial skb->dev and
>> skb->protocol in ip6_output") since it does not handles the
>> skb->dev assignment inside ip6_fragment() code path properly.
>> Need to rework and upload again
> We can avoid the revert I believe the patch is fine after analysis.
>
> Please submit this followup, thanks ! :
>
> diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c
> index 02cd44f0953900108701895108b2fdaa9f9980e5..0d6f3b6345de26c329ae1d6f25dde652a5452d4b 100644
> --- a/net/ipv6/ip6_output.c
> +++ b/net/ipv6/ip6_output.c
> @@ -869,7 +869,6 @@ int ip6_fragment(struct net *net, struct sock *sk, struct sk_buff *skb,
>   	if (skb->sk && dst_allfrag(skb_dst(skb)))
>   		sk_nocaps_add(skb->sk, NETIF_F_GSO_MASK);
>   
> -	skb->dev = skb_dst(skb)->dev;
>   	icmpv6_send(skb, ICMPV6_PKT_TOOBIG, 0, mtu);
>   	err = -EMSGSIZE;
>   
>
>
>
Thanks for the help! Patch submitted here: 
http://patchwork.ozlabs.org/patch/774260/