From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marcelo Ricardo Leitner Subject: Re: [PATCH net 2/3] sctp: hold transport before we access t->asoc in sctp proc Date: Thu, 21 Jan 2016 15:53:47 -0200 Message-ID: <20160121175347.GE3452@mrl.redhat.com> References: <4357f1f3ad90ffec1481a265d8ca198d75e25d07.1453398443.git.lucien.xin@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: network dev , linux-sctp@vger.kernel.org, Vlad Yasevich , daniel@iogearbox.net, davem@davemloft.net To: Xin Long Return-path: Received: from mx1.redhat.com ([209.132.183.28]:44590 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755545AbcAURxu (ORCPT ); Thu, 21 Jan 2016 12:53:50 -0500 Content-Disposition: inline In-Reply-To: <4357f1f3ad90ffec1481a265d8ca198d75e25d07.1453398443.git.lucien.xin@gmail.com> Sender: netdev-owner@vger.kernel.org List-ID: On Fri, Jan 22, 2016 at 01:49:08AM +0800, Xin Long wrote: > Previously, before rhashtable, /proc assoc listing was done by > read-locking the entire hash entry and dumping all assocs at once, so we > were sure that the assoc wasn't freed because it wouldn't be possible to > remove it from the hash meanwhile. > > Now we use rhashtable to list transports, and dump entries one by one. > That is, now we have to check if the assoc is still a good one, as the > transport we got may be being freed. > > Signed-off-by: Xin Long Reviewed-by: Marcelo Ricardo Leitner > --- > net/sctp/proc.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/net/sctp/proc.c b/net/sctp/proc.c > index 684c5b3..c74a810 100644 > --- a/net/sctp/proc.c > +++ b/net/sctp/proc.c > @@ -380,6 +380,8 @@ static int sctp_assocs_seq_show(struct seq_file *seq, void *v) > } > > transport = (struct sctp_transport *)v; > + if (!sctp_transport_hold(transport)) > + return 0; > assoc = transport->asoc; > epb = &assoc->base; > sk = epb->sk; > @@ -412,6 +414,8 @@ static int sctp_assocs_seq_show(struct seq_file *seq, void *v) > sk->sk_rcvbuf); > seq_printf(seq, "\n"); > > + sctp_transport_put(transport); > + > return 0; > } > > @@ -489,6 +493,8 @@ static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) > } > > tsp = (struct sctp_transport *)v; > + if (!sctp_transport_hold(tsp)) > + return 0; > assoc = tsp->asoc; > > list_for_each_entry_rcu(tsp, &assoc->peer.transport_addr_list, > @@ -544,6 +550,8 @@ static int sctp_remaddr_seq_show(struct seq_file *seq, void *v) > seq_printf(seq, "\n"); > } > > + sctp_transport_put(tsp); > + > return 0; > } > > -- > 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 >