diff options
| author |   Florin Coras <fcoras@cisco.com> | 2019-10-22 19:44:45 -0700 |
|---|---|---|
| committer |   Andrew Yourtchenko <ayourtch@gmail.com> | 2019-10-31 12:16:05 +0000 |
| commit | dcc5de6fc321c3828a7f2d55204641e198da5af2 (patch) | |
| tree | a7585f8123b977fa4766f0581b627d3c9e470c87 | |
| parent | abe07c8a25a566fd5f7441503a1541b5421c1ad7 (diff) | |
tcp: fix sack retransmit beyond snd_nxt
Type: fix
Ensure that sack retransmit logic does not try to inadvertently send new
data.
Change-Id: Idfda19643577d9c1b58e2af8d8283cabfbaf98e6
Signed-off-by: Florin Coras <fcoras@cisco.com>
(cherry picked from commit 81cb8e4092991d3fd1e24f0862c12548a2d4c714)
| -rwxr-xr-x | src/vnet/tcp/tcp_input.c | 6 | ||||
| -rw-r--r-- | src/vnet/tcp/tcp_output.c | 9 |
2 files changed, 13 insertions, 2 deletions
diff --git a/src/vnet/tcp/tcp_input.c b/src/vnet/tcp/tcp_input.c index 22222fba1e2..da499b8c720 100755 --- a/src/vnet/tcp/tcp_input.c +++ b/src/vnet/tcp/tcp_input.c @@ -890,6 +890,12 @@ scoreboard_next_rxt_hole (sack_scoreboard_t * sb, /* Rule (3): if hole not lost */ else if (seq_lt (hole->start, sb->high_sacked)) { + /* And we didn't already retransmit it */ + if (seq_leq (hole->end, sb->high_rxt)) + { + sb->cur_rxt_hole = TCP_INVALID_SACK_HOLE_INDEX; + return 0; + } *snd_limited = 0; sb->cur_rxt_hole = scoreboard_hole_index (sb, hole); } diff --git a/src/vnet/tcp/tcp_output.c b/src/vnet/tcp/tcp_output.c index 08099fffa4e..7362319646a 100644 --- a/src/vnet/tcp/tcp_output.c +++ b/src/vnet/tcp/tcp_output.c @@ -1439,6 +1439,8 @@ tcp_prepare_retransmit_segment (tcp_worker_ctx_t * wrk, max_deq_bytes = clib_min (available_bytes, max_deq_bytes); start = tc->snd_una + offset; + ASSERT (seq_leq (start + max_deq_bytes, tc->snd_nxt)); + n_bytes = tcp_prepare_segment (wrk, tc, offset, max_deq_bytes, b); if (!n_bytes) return 0; @@ -1568,7 +1570,8 @@ tcp_timer_retransmit_handler (u32 tc_index) /* Send the first unacked segment. If we're short on buffers, return * as soon as possible */ - n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, tc->snd_mss, &b); + n_bytes = clib_min (tc->snd_mss, tc->snd_nxt - tc->snd_una); + n_bytes = tcp_prepare_retransmit_segment (wrk, tc, 0, n_bytes, &b); if (!n_bytes) { tcp_timer_update (tc, TCP_TIMER_RETRANSMIT, 1); @@ -1962,7 +1965,7 @@ tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, while (snd_space > 0 && n_segs < burst_size) { - hole = scoreboard_next_rxt_hole (sb, hole, max_deq, &can_rescue, + hole = scoreboard_next_rxt_hole (sb, hole, max_deq != 0, &can_rescue, &snd_limited); if (!hole) { @@ -2030,6 +2033,8 @@ tcp_retransmit_sack (tcp_worker_ctx_t * wrk, tcp_connection_t * tc, tcp_enqueue_to_output (wrk, b, bi, tc->c_is_ip4); sb->high_rxt += n_written; + ASSERT (seq_leq (sb->high_rxt, tc->snd_nxt)); + snd_space -= n_written; n_segs += 1; } |