diff options
author | David S. Miller <davem@davemloft.net> | 2010-04-08 11:32:30 -0700 |
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committer | David S. Miller <davem@davemloft.net> | 2010-04-08 11:32:30 -0700 |
commit | 2626419ad5be1a054d350786b684b41d23de1538 (patch) | |
tree | 0fb43a4a6f01c9a50e3509b4240c018459dee12d | |
parent | 1223c67c0938d2df309fde618bd82c87c8c1af04 (diff) |
tcp: Set CHECKSUM_UNNECESSARY in tcp_init_nondata_skb
Back in commit 04a0551c87363f100b04d28d7a15a632b70e18e7
("loopback: Drop obsolete ip_summed setting") we stopped
setting CHECKSUM_UNNECESSARY in the loopback xmit.
This is because such a setting was a lie since it implies that the
checksum field of the packet is properly filled in.
Instead what happens normally is that CHECKSUM_PARTIAL is set and
skb->csum is calculated as needed.
But this was only happening for TCP data packets (via the
skb->ip_summed assignment done in tcp_sendmsg()). It doesn't
happen for non-data packets like ACKs etc.
Fix this by setting skb->ip_summed in the common non-data packet
constructor. It already is setting skb->csum to zero.
But this reminds us that we still have things like ip_output.c's
ip_dev_loopback_xmit() which sets skb->ip_summed to the value
CHECKSUM_UNNECESSARY, which Herbert's patch teaches us is not
valid. So we'll have to address that at some point too.
Signed-off-by: David S. Miller <davem@davemloft.net>
-rw-r--r-- | net/ipv4/tcp_output.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index f181b78f2385..00afbb0c7e5f 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -349,6 +349,7 @@ static inline void TCP_ECN_send(struct sock *sk, struct sk_buff *skb, */ static void tcp_init_nondata_skb(struct sk_buff *skb, u32 seq, u8 flags) { + skb->ip_summed = CHECKSUM_PARTIAL; skb->csum = 0; TCP_SKB_CB(skb)->flags = flags; |