diff options
| author | Eric Dumazet <edumazet@google.com> | 2024-04-25 19:34:50 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2024-04-26 13:55:29 -0700 |
| commit | 1bede0a12d3a45bd366d3cf9e1c7611d86f1bc1f (patch) | |
| tree | c5790b9f11b064ab3ff7796f131e60cf6693c529 | |
| parent | 8880e2666fa87a7d62a60fea9fe9ed9ba21ddcf7 (diff) | |
| download | next-queue-1bede0a12d3a45bd366d3cf9e1c7611d86f1bc1f.tar.gz | |
tcp: fix tcp_grow_skb() vs tstamps
I forgot to call tcp_skb_collapse_tstamp() in the
case we consume the second skb in write queue.
Neal suggested to create a common helper used by tcp_mtu_probe()
and tcp_grow_skb().
Fixes: 8ee602c63520 ("tcp: try to send bigger TSO packets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Link: https://lore.kernel.org/r/20240425193450.411640-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| -rw-r--r-- | net/ipv4/tcp_output.c | 33 |
1 files changed, 19 insertions, 14 deletions
diff --git a/net/ipv4/tcp_output.c b/net/ipv4/tcp_output.c index ece4726c87510..ea7ad7d99245c 100644 --- a/net/ipv4/tcp_output.c +++ b/net/ipv4/tcp_output.c @@ -2403,6 +2403,21 @@ commit: return 0; } +/* tcp_mtu_probe() and tcp_grow_skb() can both eat an skb (src) if + * all its payload was moved to another one (dst). + * Make sure to transfer tcp_flags, eor, and tstamp. + */ +static void tcp_eat_one_skb(struct sock *sk, + struct sk_buff *dst, + struct sk_buff *src) +{ + TCP_SKB_CB(dst)->tcp_flags |= TCP_SKB_CB(src)->tcp_flags; + TCP_SKB_CB(dst)->eor = TCP_SKB_CB(src)->eor; + tcp_skb_collapse_tstamp(dst, src); + tcp_unlink_write_queue(src, sk); + tcp_wmem_free_skb(sk, src); +} + /* Create a new MTU probe if we are ready. * MTU probe is regularly attempting to increase the path MTU by * deliberately sending larger packets. This discovers routing @@ -2508,16 +2523,7 @@ static int tcp_mtu_probe(struct sock *sk) copy = min_t(int, skb->len, probe_size - len); if (skb->len <= copy) { - /* We've eaten all the data from this skb. - * Throw it away. */ - TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags; - /* If this is the last SKB we copy and eor is set - * we need to propagate it to the new skb. - */ - TCP_SKB_CB(nskb)->eor = TCP_SKB_CB(skb)->eor; - tcp_skb_collapse_tstamp(nskb, skb); - tcp_unlink_write_queue(skb, sk); - tcp_wmem_free_skb(sk, skb); + tcp_eat_one_skb(sk, nskb, skb); } else { TCP_SKB_CB(nskb)->tcp_flags |= TCP_SKB_CB(skb)->tcp_flags & ~(TCPHDR_FIN|TCPHDR_PSH); @@ -2705,11 +2711,10 @@ static void tcp_grow_skb(struct sock *sk, struct sk_buff *skb, int amount) TCP_SKB_CB(next_skb)->seq += nlen; if (!next_skb->len) { + /* In case FIN is set, we need to update end_seq */ TCP_SKB_CB(skb)->end_seq = TCP_SKB_CB(next_skb)->end_seq; - TCP_SKB_CB(skb)->eor = TCP_SKB_CB(next_skb)->eor; - TCP_SKB_CB(skb)->tcp_flags |= TCP_SKB_CB(next_skb)->tcp_flags; - tcp_unlink_write_queue(next_skb, sk); - tcp_wmem_free_skb(sk, next_skb); + + tcp_eat_one_skb(sk, skb, next_skb); } } |