diff options
| author | Herbert Xu <herbert@gondor.apana.org.au> | 2005-09-14 20:50:35 -0700 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2005-09-14 20:50:35 -0700 |
| commit | 3c05d92ed49f644d1f5a960fa48637d63b946016 (patch) | |
| tree | 4882f2b114f7bb497e9844e21fe8bff4f8160def | |
| parent | 1619cca2921f6927f4240e03f413d4165c7002fc (diff) | |
| download | lwn-3c05d92ed49f644d1f5a960fa48637d63b946016.tar.gz lwn-3c05d92ed49f644d1f5a960fa48637d63b946016.zip | |
[TCP]: Compute in_sacked properly when we split up a TSO frame.
The problem is that the SACK fragmenting code may incorrectly call
tcp_fragment() with a length larger than the skb->len. This happens
when the skb on the transmit queue completely falls to the LHS of the
SACK.
And add a BUG() check to tcp_fragment() so we can spot this kind of
error more quickly in the future.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/ipv4/tcp_input.c | 16 | ||||
| -rw-r--r-- | net/ipv4/tcp_output.c | 2 |
2 files changed, 11 insertions, 7 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 29222b964951..a7537c7bbd06 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -979,14 +979,19 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ if (!before(TCP_SKB_CB(skb)->seq, end_seq)) break; + in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq) && + !before(end_seq, TCP_SKB_CB(skb)->end_seq); + pcount = tcp_skb_pcount(skb); - if (pcount > 1 && - (after(start_seq, TCP_SKB_CB(skb)->seq) || - before(end_seq, TCP_SKB_CB(skb)->end_seq))) { + if (pcount > 1 && !in_sack && + after(TCP_SKB_CB(skb)->end_seq, start_seq)) { unsigned int pkt_len; - if (after(start_seq, TCP_SKB_CB(skb)->seq)) + in_sack = !after(start_seq, + TCP_SKB_CB(skb)->seq); + + if (!in_sack) pkt_len = (start_seq - TCP_SKB_CB(skb)->seq); else @@ -999,9 +1004,6 @@ tcp_sacktag_write_queue(struct sock *sk, struct sk_buff *ack_skb, u32 prior_snd_ fack_count += pcount; - in_sack = !after(start_seq, TCP_SKB_CB(skb)->seq) && - !before(end_seq, TCP_SKB_CB(skb)->end_seq); - sacked = TCP_SKB_CB(skb)->sacked; /* Account D-SACK for retransmitted packet. */ diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index c10e4435e3b1..b018e31b6530 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -435,6 +435,8 @@ int tcp_fragment(struct sock *sk, struct sk_buff *skb, u32 len, unsigned int mss int nsize, old_factor; u16 flags; + BUG_ON(len >= skb->len); + nsize = skb_headlen(skb) - len; if (nsize < 0) nsize = 0; |