diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2006-06-25 23:55:46 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-06-25 23:55:46 -0700 |
| commit | 0718bcc09b3597c51e87f265c72135a4928d3c0b (patch) | |
| tree | fd4a686629488bad28f3c780e6b2b52803698877 /net/ipv4 | |
| parent | 3ba07e65b288f00cc4d2420f1da46309b1cb5a0c (diff) | |
[NET]: Fix CHECKSUM_HW GSO problems.
Fix checksum problems in the GSO code path for CHECKSUM_HW packets.
The ipv4 TCP pseudo header checksum has to be adjusted for GSO
segmented packets.
The adjustment is needed because the length field in the pseudo-header
changes. However, because we have the inequality oldlen > newlen, we
know that delta = (u16)~oldlen + newlen is still a 16-bit quantity.
This also means that htonl(delta) + th->check still fits in 32 bits.
Therefore we don't have to use csum_add on this operations.
This is based on a patch by Michael Chan <mchan@broadcom.com>.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp.c | 22 |
1 files changed, 11 insertions, 11 deletions
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index 0e029c4e2903..c04176be7ed1 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -2166,7 +2166,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int sg) if (!pskb_may_pull(skb, thlen)) goto out; - oldlen = ~htonl(skb->len); + oldlen = (u16)~skb->len; __skb_pull(skb, thlen); segs = skb_segment(skb, sg); @@ -2174,7 +2174,7 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int sg) goto out; len = skb_shinfo(skb)->gso_size; - delta = csum_add(oldlen, htonl(thlen + len)); + delta = htonl(oldlen + (thlen + len)); skb = segs; th = skb->h.th; @@ -2183,10 +2183,10 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int sg) do { th->fin = th->psh = 0; - if (skb->ip_summed == CHECKSUM_NONE) { - th->check = csum_fold(csum_partial( - skb->h.raw, thlen, csum_add(skb->csum, delta))); - } + th->check = ~csum_fold(th->check + delta); + if (skb->ip_summed != CHECKSUM_HW) + th->check = csum_fold(csum_partial(skb->h.raw, thlen, + skb->csum)); seq += len; skb = skb->next; @@ -2196,11 +2196,11 @@ struct sk_buff *tcp_tso_segment(struct sk_buff *skb, int sg) th->cwr = 0; } while (skb->next); - if (skb->ip_summed == CHECKSUM_NONE) { - delta = csum_add(oldlen, htonl(skb->tail - skb->h.raw)); - th->check = csum_fold(csum_partial( - skb->h.raw, thlen, csum_add(skb->csum, delta))); - } + delta = htonl(oldlen + (skb->tail - skb->h.raw) + skb->data_len); + th->check = ~csum_fold(th->check + delta); + if (skb->ip_summed != CHECKSUM_HW) + th->check = csum_fold(csum_partial(skb->h.raw, thlen, + skb->csum)); out: return segs; |