diff options
| author | Eric Dumazet <edumazet@google.com> | 2022-04-06 02:35:38 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2022-04-06 22:05:41 +0300 |
| commit | 40570375356c874b1578e05c1dcc3ff7c1322dbe (patch) | |
| tree | 54c7a52bfdd4e302f877e93dc94adb09cfa3aac4 /include/trace | |
| parent | 487dc3ca60e3e420d54bcc613cb49e8e85f34569 (diff) | |
| download | linux-40570375356c874b1578e05c1dcc3ff7c1322dbe.tar.xz | |
tcp: add accessors to read/set tp->snd_cwnd
We had various bugs over the years with code
breaking the assumption that tp->snd_cwnd is greater
than zero.
Lately, syzbot reported the WARN_ON_ONCE(!tp->prior_cwnd) added
in commit 8b8a321ff72c ("tcp: fix zero cwnd in tcp_cwnd_reduction")
can trigger, and without a repro we would have to spend
considerable time finding the bug.
Instead of complaining too late, we want to catch where
and when tp->snd_cwnd is set to an illegal value.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Suggested-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Link: https://lore.kernel.org/r/20220405233538.947344-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/trace')
| -rw-r--r-- | include/trace/events/tcp.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/include/trace/events/tcp.h b/include/trace/events/tcp.h index 521059d8dc0a..edcd6369de10 100644 --- a/include/trace/events/tcp.h +++ b/include/trace/events/tcp.h @@ -279,7 +279,7 @@ TRACE_EVENT(tcp_probe, __entry->data_len = skb->len - __tcp_hdrlen(th); __entry->snd_nxt = tp->snd_nxt; __entry->snd_una = tp->snd_una; - __entry->snd_cwnd = tp->snd_cwnd; + __entry->snd_cwnd = tcp_snd_cwnd(tp); __entry->snd_wnd = tp->snd_wnd; __entry->rcv_wnd = tp->rcv_wnd; __entry->ssthresh = tcp_current_ssthresh(sk); |