diff options
| author | Neal Cardwell <ncardwell@google.com> | 2012-02-12 18:37:10 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-02-29 16:34:16 -0800 |
| commit | dd31c1ce7ef7b363215081fde02f13bf3e50b5a1 (patch) | |
| tree | 8080df1b00e528814195a69f24fd6508d0554623 /net/ipv4 | |
| parent | 382e8f84cb3db5295aa2f142a11e42eac6544ab4 (diff) | |
tcp: fix range tcp_shifted_skb() passes to tcp_sacktag_one()
[ Upstream commit daef52bab1fd26e24e8e9578f8fb33ba1d0cb412 ]
Fix the newly-SACKed range to be the range of newly-shifted bytes.
Previously - since 832d11c5cd076abc0aa1eaf7be96c81d1a59ce41 -
tcp_shifted_skb() incorrectly called tcp_sacktag_one() with the start
and end sequence numbers of the skb it passes in set to the range just
beyond the range that is newly-SACKed.
This commit also removes a special-case adjustment to lost_cnt_hint in
tcp_shifted_skb() since the pre-existing adjustment of lost_cnt_hint
in tcp_sacktag_one() now properly handles this things now that the
correct start sequence number is passed in.
Signed-off-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/ipv4')
| -rw-r--r-- | net/ipv4/tcp_input.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index af41044c605a..78689e56936d 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -1370,6 +1370,9 @@ static u8 tcp_sacktag_one(struct sock *sk, return sacked; } +/* Shift newly-SACKed bytes from this skb to the immediately previous + * already-SACKed sk_buff. Mark the newly-SACKed bytes as such. + */ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, struct tcp_sacktag_state *state, unsigned int pcount, int shifted, int mss, @@ -1377,12 +1380,11 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *prev = tcp_write_queue_prev(sk, skb); + u32 start_seq = TCP_SKB_CB(skb)->seq; /* start of newly-SACKed */ + u32 end_seq = start_seq + shifted; /* end of newly-SACKed */ BUG_ON(!pcount); - if (skb == tp->lost_skb_hint) - tp->lost_cnt_hint += pcount; - TCP_SKB_CB(prev)->end_seq += shifted; TCP_SKB_CB(skb)->seq += shifted; @@ -1406,12 +1408,11 @@ static int tcp_shifted_skb(struct sock *sk, struct sk_buff *skb, skb_shinfo(skb)->gso_type = 0; } - /* We discard results */ - tcp_sacktag_one(sk, state, - TCP_SKB_CB(skb)->sacked, - TCP_SKB_CB(skb)->seq, - TCP_SKB_CB(skb)->end_seq, - dup_sack, pcount); + /* Adjust counters and hints for the newly sacked sequence range but + * discard the return value since prev is already marked. + */ + tcp_sacktag_one(sk, state, TCP_SKB_CB(skb)->sacked, + start_seq, end_seq, dup_sack, pcount); /* Difference in this won't matter, both ACKed by the same cumul. ACK */ TCP_SKB_CB(prev)->sacked |= (TCP_SKB_CB(skb)->sacked & TCPCB_EVER_RETRANS); |