| Message ID | 20170714214925.30720-4-ncardwell@google.com |
|---|---|
| State | Accepted, archived |
| Delegated to: | David Miller |
| Headers | show |
diff --git a/net/ipv4/tcp_bbr.c b/net/ipv4/tcp_bbr.c index 3276140c2506..42e0017f2ebc 100644 --- a/net/ipv4/tcp_bbr.c +++ b/net/ipv4/tcp_bbr.c @@ -837,7 +837,6 @@ static void bbr_init(struct sock *sk) minmax_reset(&bbr->bw, bbr->rtt_cnt, 0); /* init max bw to 0 */ - sk->sk_pacing_rate = 0; /* force an update of sk_pacing_rate */ bbr_init_pacing_rate_from_rtt(sk); bbr->restore_cwnd = 0;
Fix a corner case noticed by Eric Dumazet, where BBR's setting sk->sk_pacing_rate to 0 during initialization could theoretically cause packets in the sending host to hang if there were packets "in flight" in the pacing infrastructure at the time the BBR congestion control state is initialized. This could occur if the pacing infrastructure happened to race with bbr_init() in a way such that the pacer read the 0 rather than the immediately following non-zero pacing rate. Fixes: 0f8782ea1497 ("tcp_bbr: add BBR congestion control") Reported-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Neal Cardwell <ncardwell@google.com> Signed-off-by: Yuchung Cheng <ycheng@google.com> Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com> --- net/ipv4/tcp_bbr.c | 1 - 1 file changed, 1 deletion(-)