From: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
To: Xin Long <lucien.xin@gmail.com>
Cc: network dev <netdev@vger.kernel.org>,
linux-sctp@vger.kernel.org, davem@davemloft.net,
Vlad Yasevich <vyasevich@gmail.com>,
daniel@iogearbox.net
Subject: Re: [PATCH net] sctp: allow delivering notifications after receiving SHUTDOWN
Date: Sat, 30 Jul 2016 13:22:31 +0000 [thread overview]
Message-ID: <20160730132231.GD2957@localhost.localdomain> (raw)
In-Reply-To: <b188a1ce183303d7d9cd9fc7ccd5d113c520980e.1469858949.git.lucien.xin@gmail.com>
On Sat, Jul 30, 2016 at 02:09:09PM +0800, Xin Long wrote:
> Prior to this patch, once sctp received SHUTDOWN or shutdown with RD,
> sk->sk_shutdown would be set with RCV_SHUTDOWN, and all events would
> be dropped in sctp_ulpq_tail_event(). It would cause:
>
> 1. some notifications couldn't be received by users. like
> SCTP_SHUTDOWN_COMP generated by sctp_sf_do_4_C().
>
> 2. sctp would also never trigger sk_data_ready when the association
> was closed, making it harder to identify the end of the association
> by calling recvmsg() and getting an EOF. It was not convenient for
> kernel users.
>
> The check here should be stopping delivering DATA chunks after receiving
> SHUTDOWN, and stopping delivering ANY chunks after sctp_close().
>
> So this patch is to allow notifications to enqueue into receive queue
> even if sk->sk_shutdown is set to RCV_SHUTDOWN in sctp_ulpq_tail_event,
> but if sk->sk_shutdown = RCV_SHUTDOWN | SEND_SHUTDOWN, it drops all
> events.
>
> Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
> ---
> net/sctp/ulpqueue.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/net/sctp/ulpqueue.c b/net/sctp/ulpqueue.c
> index ec166d2..877e550 100644
> --- a/net/sctp/ulpqueue.c
> +++ b/net/sctp/ulpqueue.c
> @@ -204,7 +204,9 @@ int sctp_ulpq_tail_event(struct sctp_ulpq *ulpq, struct sctp_ulpevent *event)
> /* If the socket is just going to throw this away, do not
> * even try to deliver it.
> */
> - if (sock_flag(sk, SOCK_DEAD) || (sk->sk_shutdown & RCV_SHUTDOWN))
> + if (sk->sk_shutdown & RCV_SHUTDOWN &&
> + (sk->sk_shutdown & SEND_SHUTDOWN ||
> + !sctp_ulpevent_is_notification(event)))
> goto out_free;
>
> if (!sctp_ulpevent_is_notification(event)) {
> --
> 2.1.0
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-sctp" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>
next prev parent reply other threads:[~2016-07-30 13:22 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-30 6:09 [PATCH net] sctp: allow delivering notifications after receiving SHUTDOWN Xin Long
2016-07-30 13:22 ` Marcelo Ricardo Leitner [this message]
2016-07-31 5:07 ` David Miller
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160730132231.GD2957@localhost.localdomain \
--to=marcelo.leitner@gmail.com \
--cc=daniel@iogearbox.net \
--cc=davem@davemloft.net \
--cc=linux-sctp@vger.kernel.org \
--cc=lucien.xin@gmail.com \
--cc=netdev@vger.kernel.org \
--cc=vyasevich@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).