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* [PATCH] tcp: remove duplicate th = tcp_hdr(skb)
@ 2011-01-13 15:41 Christoph Paasch
  2011-01-13 15:54 ` Jesse Gross
  2011-01-13 15:59 ` Eric Dumazet
  0 siblings, 2 replies; 3+ messages in thread
From: Christoph Paasch @ 2011-01-13 15:41 UTC (permalink / raw)
  To: davem, netdev; +Cc: Christoph Paasch

th is already set some lines before to be th = tcp_hdr(skb).

Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
---
 net/ipv4/tcp_ipv4.c |    1 -
 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
index 856f684..7fe29c6 100644
--- a/net/ipv4/tcp_ipv4.c
+++ b/net/ipv4/tcp_ipv4.c
@@ -1644,7 +1644,6 @@ int tcp_v4_rcv(struct sk_buff *skb)
 	if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb))
 		goto bad_packet;
 
-	th = tcp_hdr(skb);
 	iph = ip_hdr(skb);
 	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
 	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +
-- 
1.7.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] tcp: remove duplicate th = tcp_hdr(skb)
  2011-01-13 15:41 [PATCH] tcp: remove duplicate th = tcp_hdr(skb) Christoph Paasch
@ 2011-01-13 15:54 ` Jesse Gross
  2011-01-13 15:59 ` Eric Dumazet
  1 sibling, 0 replies; 3+ messages in thread
From: Jesse Gross @ 2011-01-13 15:54 UTC (permalink / raw)
  To: Christoph Paasch; +Cc: davem, netdev

On Thu, Jan 13, 2011 at 10:41 AM, Christoph Paasch
<christoph.paasch@uclouvain.be> wrote:
> th is already set some lines before to be th = tcp_hdr(skb).
>
> Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
> ---
>  net/ipv4/tcp_ipv4.c |    1 -
>  1 files changed, 0 insertions(+), 1 deletions(-)
>
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index 856f684..7fe29c6 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -1644,7 +1644,6 @@ int tcp_v4_rcv(struct sk_buff *skb)
>        if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb))
>                goto bad_packet;
>
> -       th = tcp_hdr(skb);

It needs to be reloaded because pskb_may_pull() may reallocate the buffer.

^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] tcp: remove duplicate th = tcp_hdr(skb)
  2011-01-13 15:41 [PATCH] tcp: remove duplicate th = tcp_hdr(skb) Christoph Paasch
  2011-01-13 15:54 ` Jesse Gross
@ 2011-01-13 15:59 ` Eric Dumazet
  1 sibling, 0 replies; 3+ messages in thread
From: Eric Dumazet @ 2011-01-13 15:59 UTC (permalink / raw)
  To: Christoph Paasch; +Cc: davem, netdev

Le jeudi 13 janvier 2011 à 16:41 +0100, Christoph Paasch a écrit :
> th is already set some lines before to be th = tcp_hdr(skb).
> 
> Signed-off-by: Christoph Paasch <christoph.paasch@uclouvain.be>
> ---
>  net/ipv4/tcp_ipv4.c |    1 -
>  1 files changed, 0 insertions(+), 1 deletions(-)
> 
> diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c
> index 856f684..7fe29c6 100644
> --- a/net/ipv4/tcp_ipv4.c
> +++ b/net/ipv4/tcp_ipv4.c
> @@ -1644,7 +1644,6 @@ int tcp_v4_rcv(struct sk_buff *skb)
>  	if (!skb_csum_unnecessary(skb) && tcp_v4_checksum_init(skb))
>  		goto bad_packet;
>  

Well... no please.

> -	th = tcp_hdr(skb);
>  	iph = ip_hdr(skb);
>  	TCP_SKB_CB(skb)->seq = ntohl(th->seq);
>  	TCP_SKB_CB(skb)->end_seq = (TCP_SKB_CB(skb)->seq + th->syn + th->fin +

Hint : pskb_may_pull() can change tcp_hdr(skb) result.



^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2011-01-13 15:59 UTC | newest]

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2011-01-13 15:41 [PATCH] tcp: remove duplicate th = tcp_hdr(skb) Christoph Paasch
2011-01-13 15:54 ` Jesse Gross
2011-01-13 15:59 ` Eric Dumazet

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