When tcp_collapse() rebuilds skbs under memory pressure, the copy process doesn't include the right tstamp and hwtstamp from the old skb. In net timestamping case, if such an skb happens to be the last one consumed in a recvmsg() call, the application receives no RX timestamp for that call. Fix this by copying both tstamp and hwtstamp to the new skb right after the initialization. Fixes: 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") Signed-off-by: Jason Xing --- net/ipv4/tcp_input.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c index 0f60a1dbf927..c5756db892f2 100644 --- a/net/ipv4/tcp_input.c +++ b/net/ipv4/tcp_input.c @@ -5835,6 +5835,8 @@ tcp_collapse(struct sock *sk, struct sk_buff_head *list, struct rb_root *root, memcpy(nskb->cb, skb->cb, sizeof(skb->cb)); skb_copy_decrypted(nskb, skb); + nskb->tstamp = skb->tstamp; + skb_hwtstamps(nskb)->hwtstamp = skb_hwtstamps(skb)->hwtstamp; TCP_SKB_CB(nskb)->seq = TCP_SKB_CB(nskb)->end_seq = start; if (list) __skb_queue_before(list, skb, nskb); -- 2.43.5