diff options
| author | Ryan Stone <rstone@FreeBSD.org> | 2022-02-08 15:08:50 +0000 |
|---|---|---|
| committer | Hans Petter Selasky <hselasky@FreeBSD.org> | 2022-02-08 15:08:50 +0000 |
| commit | 4287b7caa921131845837dd394581d0246f38eb1 (patch) | |
| tree | e492872cc8341bc0e21cec2d268a665fcd51386b | |
| parent | 22b24dc1abb3bc41c9b54054c2242b525daa5bfc (diff) | |
| download | src-4287b7caa921131845837dd394581d0246f38eb1.tar.gz src-4287b7caa921131845837dd394581d0246f38eb1.zip | |
LRO: Don't merge ACK and non-ACK packets together
LRO was willing to merge ACK and non-ACK packets together. This
can cause incorrect th_ack values to be reported up the stack.
While non-ACKs are quite unlikely to appear in practice, LRO's
behaviour is against the spec. Make LRO unwilling to merge
packets with different TH_ACK flag values in order to fix the
issue.
Found by: Sysunit test
Differential Revision: https://reviews.freebsd.org/D33775
Reviewed by: rrs
(cherry picked from commit 3284f4925f697ad7cc2aa4761ff5cf6ce98fd623)
| -rw-r--r-- | sys/netinet/tcp_lro.c | 5 | ||||
| -rw-r--r-- | sys/netinet/tcp_lro.h | 5 |
2 files changed, 7 insertions, 3 deletions
diff --git a/sys/netinet/tcp_lro.c b/sys/netinet/tcp_lro.c index feec8c36ab69..cfc84707abd2 100644 --- a/sys/netinet/tcp_lro.c +++ b/sys/netinet/tcp_lro.c @@ -895,6 +895,7 @@ tcp_set_entry_to_mbuf(struct lro_ctrl *lc, struct lro_entry *le, le->next_seq = ntohl(th->th_seq) + tcp_data_len; le->ack_seq = th->th_ack; le->window = th->th_win; + le->flags = th->th_flags; le->needs_merge = 0; /* Setup new data pointers. */ @@ -1066,10 +1067,12 @@ again: } /* Try to append the new segment. */ if (__predict_false(ntohl(th->th_seq) != le->next_seq || + ((th->th_flags & TH_ACK) != + (le->flags & TH_ACK)) || (tcp_data_len == 0 && le->ack_seq == th->th_ack && le->window == th->th_win))) { - /* Out of order packet or duplicate ACK. */ + /* Out of order packet, non-ACK + ACK or dup ACK. */ tcp_push_and_replace(lc, le, m); goto again; } diff --git a/sys/netinet/tcp_lro.h b/sys/netinet/tcp_lro.h index 97819596231e..b8abc2fa1ab3 100644 --- a/sys/netinet/tcp_lro.h +++ b/sys/netinet/tcp_lro.h @@ -146,8 +146,9 @@ struct lro_entry { uint16_t compressed; uint16_t uncompressed; uint16_t window; - uint16_t timestamp : 1; - uint16_t needs_merge : 1; + uint8_t flags; + uint8_t timestamp : 1; + uint8_t needs_merge : 1; struct bintime alloc_time; /* time when entry was allocated */ }; |