tcp: clear SACK state when scoreboard is forcefully freed
ClosedPublic
Actions

Authored by rscheff on Oct 11 2023, 8:02 PM.

Details

Reviewers

pho
tuexen
rrs
cc
glebius

Group Reviewers

transport

Commits

rG91ee2d8d9a67: tcp: clear SACK state when scoreboard is forcefully freed

Summary

When a RTO happens during an on-going SACK loss recovery
episode, the internal summary accounting is not cleared.
This may lead to subsequent errors in calculations
(e.g. IsLost()).

PR: 274406
Reported by: pho

Diff Detail

Repository

rG FreeBSD src repository

Lint

Lint Passed

Unit

No Test Coverage

Build Status

Buildable 53931
Build 50821: arc lint + arc unit

Event Timeline

rscheff created this revision.Oct 11 2023, 8:02 PM

Herald added a reviewer: transport. · View Herald TranscriptOct 11 2023, 8:02 PM

Herald added subscribers: melifaro, imp. · View Herald Transcript

rscheff requested review of this revision.Oct 11 2023, 8:02 PM

Harbormaster completed remote builds in B53931: Diff 128612.Oct 11 2023, 8:02 PM

tuexen accepted this revision.Oct 11 2023, 8:06 PM

This revision is now accepted and ready to land.Oct 11 2023, 8:06 PM

Closed by commit rG91ee2d8d9a67: tcp: clear SACK state when scoreboard is forcefully freed (authored by rscheff). · Explain WhyOct 11 2023, 9:11 PM

This revision was automatically updated to reflect the committed changes.

rscheff added a commit: rG91ee2d8d9a67: tcp: clear SACK state when scoreboard is forcefully freed.

cc added inline comments.Oct 11 2023, 9:19 PM

sys/netinet/tcp_sack.c
891	Better keep the fields in order like in the struct sackhint definition. tp->sackhint.delivered_data = 0; tp->sackhint.sacked_bytes = 0; tp->sackhint.hole_bytes = 0; tp->sackhint.lost_bytes = 0;

This change fixes the panic I saw.

rscheff edited the summary of this revision. (Show Details)Oct 11 2023, 9:26 PM

rscheff edited the test plan for this revision. (Show Details)

rscheff marked an inline comment as done.Oct 11 2023, 9:29 PM

rscheff added inline comments.

sys/netinet/tcp_sack.c
891	I trust gcc to do simple reorders like this for more effective data access. Already committed to fix an ongoing panic.

Revision Contents
Changeset List

Path

Size

sys/

netinet/

tcp_sack.c

4 lines

Diff 128612

View Options

tcp: clear SACK state when scoreboard is forcefully freedClosedPublicActions