Author: tuexen Date: Wed Sep 4 04:38:31 2019 New Revision: 351801 URL: https://svnweb.freebsd.org/changeset/base/351801
Log: Fix the SACK block generation in the base TCP stack by bringing it in sync with the RACK stack. Reviewed by: rrs@ MFC after: 5 days Sponsored by: Netflix, Inc. Differential Revision: https://reviews.freebsd.org/D21513 Modified: head/sys/netinet/tcp_input.c Modified: head/sys/netinet/tcp_input.c ============================================================================== --- head/sys/netinet/tcp_input.c Tue Sep 3 22:26:01 2019 (r351800) +++ head/sys/netinet/tcp_input.c Wed Sep 4 04:38:31 2019 (r351801) @@ -2264,7 +2264,8 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, stru * DSACK - add SACK block for dropped range */ if (tp->t_flags & TF_SACK_PERMIT) { - tcp_update_sack_list(tp, th->th_seq, th->th_seq+tlen); + tcp_update_sack_list(tp, th->th_seq, + th->th_seq + todrop); /* * ACK now, as the next in-sequence segment * will clear the DSACK block again @@ -3051,21 +3052,29 @@ dodata: /* XXX */ * DSACK actually handled in the fastpath * above. */ - tcp_update_sack_list(tp, save_start, save_start + save_tlen); - } else - if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { + tcp_update_sack_list(tp, save_start, + save_start + save_tlen); + } else if ((tlen > 0) && SEQ_GT(tp->rcv_nxt, save_rnxt)) { /* * Cleaning sackblks by using zero length * update. */ - tcp_update_sack_list(tp, save_start, save_start); - } else - if ((tlen > 0) && (tlen >= save_tlen)) { + if ((tp->rcv_numsacks >= 1) && + (tp->sackblks[0].end == save_start)) { + /* partial overlap, recorded at todrop above */ + tcp_update_sack_list(tp, tp->sackblks[0].start, + tp->sackblks[0].end); + } else { + tcp_update_dsack_list(tp, save_start, + save_start + save_tlen); + } + } else if ((tlen > 0) && (tlen >= save_tlen)) { /* Update of sackblks. */ - tcp_update_sack_list(tp, save_start, save_start + save_tlen); - } else - if (tlen > 0) { - tcp_update_sack_list(tp, save_start, save_start+tlen); + tcp_update_dsack_list(tp, save_start, + save_start + save_tlen); + } else if (tlen > 0) { + tcp_update_dsack_list(tp, save_start, + save_start + tlen); } } #if 0 _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
