5.4-stable review patch. If anyone has any objections, please let me know.
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From: zhang kai zhangkaiheb@126.com
[ Upstream commit 636ef28d6e4d174e424102466caf572b0406fb0e ]
so tcp_is_sack/reno checks are removed from tcp_mark_head_lost.
Signed-off-by: zhang kai zhangkaiheb@126.com Acked-by: Neal Cardwell ncardwell@google.com Signed-off-by: David S. Miller davem@davemloft.net Stable-dep-of: a6458ab7fd4f ("UPSTREAM: tcp: fix DSACK undo in fast recovery to call tcp_try_to_open()") Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv4/tcp_input.c | 32 +++++++------------------------- 1 file changed, 7 insertions(+), 25 deletions(-)
diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 87a10bb11eb0b..dc446d7c9e0f2 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -2202,8 +2202,7 @@ static bool tcp_time_to_recover(struct sock *sk, int flag) }
/* Detect loss in event "A" above by marking head of queue up as lost. - * For non-SACK(Reno) senders, the first "packets" number of segments - * are considered lost. For RFC3517 SACK, a segment is considered lost if it + * For RFC3517 SACK, a segment is considered lost if it * has at least tp->reordering SACKed seqments above it; "packets" refers to * the maximum SACKed segments to pass before reaching this limit. */ @@ -2211,10 +2210,9 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head) { struct tcp_sock *tp = tcp_sk(sk); struct sk_buff *skb; - int cnt, oldcnt, lost; - unsigned int mss; + int cnt; /* Use SACK to deduce losses of new sequences sent during recovery */ - const u32 loss_high = tcp_is_sack(tp) ? tp->snd_nxt : tp->high_seq; + const u32 loss_high = tp->snd_nxt;
WARN_ON(packets > tp->packets_out); skb = tp->lost_skb_hint; @@ -2237,26 +2235,11 @@ static void tcp_mark_head_lost(struct sock *sk, int packets, int mark_head) if (after(TCP_SKB_CB(skb)->end_seq, loss_high)) break;
- oldcnt = cnt; - if (tcp_is_reno(tp) || - (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED)) + if (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) cnt += tcp_skb_pcount(skb);
- if (cnt > packets) { - if (tcp_is_sack(tp) || - (TCP_SKB_CB(skb)->sacked & TCPCB_SACKED_ACKED) || - (oldcnt >= packets)) - break; - - mss = tcp_skb_mss(skb); - /* If needed, chop off the prefix to mark as lost. */ - lost = (packets - oldcnt) * mss; - if (lost < skb->len && - tcp_fragment(sk, TCP_FRAG_IN_RTX_QUEUE, skb, - lost, mss, GFP_ATOMIC) < 0) - break; - cnt = packets; - } + if (cnt > packets) + break;
tcp_skb_mark_lost(tp, skb);
@@ -2883,8 +2866,7 @@ static void tcp_fastretrans_alert(struct sock *sk, const u32 prior_snd_una, if (tcp_try_undo_partial(sk, prior_snd_una)) return; /* Partial ACK arrived. Force fast retransmit. */ - do_lost = tcp_is_reno(tp) || - tcp_force_fast_retransmit(sk); + do_lost = tcp_force_fast_retransmit(sk); } if (tcp_try_undo_dsack(sk)) { tcp_try_keep_open(sk);