summaryrefslogtreecommitdiff
path: root/net/ipv4
diff options
context:
space:
mode:
authorNeal Cardwell <ncardwell@google.com>2012-02-12 18:37:10 +0000
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2012-02-29 16:34:16 -0800
commitdd31c1ce7ef7b363215081fde02f13bf3e50b5a1 (patch)
tree8080df1b00e528814195a69f24fd6508d0554623 /net/ipv4
parent382e8f84cb3db5295aa2f142a11e42eac6544ab4 (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.c19
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);