From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752713AbeE3LU0 (ORCPT ); Wed, 30 May 2018 07:20:26 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:60999 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752552AbeE3LHH (ORCPT ); Wed, 30 May 2018 07:07:07 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Johannes Berg" , "Nicolas Dichtel" , "David S. Miller" Date: Wed, 30 May 2018 11:52:41 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [PATCH 3.2 078/153] netlink: ensure to loop over all netns in genlmsg_multicast_allns() In-Reply-To: X-SA-Exim-Connect-IP: 2a02:8011:400e:2:6f00:88c8:c921:d332 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2.102-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Nicolas Dichtel commit cb9f7a9a5c96a773bbc9c70660dc600cfff82f82 upstream. Nowadays, nlmsg_multicast() returns only 0 or -ESRCH but this was not the case when commit 134e63756d5f was pushed. However, there was no reason to stop the loop if a netns does not have listeners. Returns -ESRCH only if there was no listeners in all netns. To avoid having the same problem in the future, I didn't take the assumption that nlmsg_multicast() returns only 0 or -ESRCH. Fixes: 134e63756d5f ("genetlink: make netns aware") CC: Johannes Berg Signed-off-by: Nicolas Dichtel Signed-off-by: David S. Miller [bwh: Backported to 3.2: s/portid/pid/] Signed-off-by: Ben Hutchings --- net/netlink/genetlink.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -917,6 +917,7 @@ static int genlmsg_mcast(struct sk_buff { struct sk_buff *tmp; struct net *net, *prev = NULL; + bool delivered = false; int err; for_each_net_rcu(net) { @@ -928,14 +929,21 @@ static int genlmsg_mcast(struct sk_buff } err = nlmsg_multicast(prev->genl_sock, tmp, pid, group, flags); - if (err) + if (!err) + delivered = true; + else if (err != -ESRCH) goto error; } prev = net; } - return nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); + err = nlmsg_multicast(prev->genl_sock, skb, pid, group, flags); + if (!err) + delivered = true; + else if (err != -ESRCH) + goto error; + return delivered ? 0 : -ESRCH; error: kfree_skb(skb); return err;