From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 323D2C65BAF for ; Sun, 9 Dec 2018 21:58:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 0010520661 for ; Sun, 9 Dec 2018 21:58:24 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0010520661 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=decadent.org.uk Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727107AbeLIV6Y (ORCPT ); Sun, 9 Dec 2018 16:58:24 -0500 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:36246 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726754AbeLIVzj (ORCPT ); Sun, 9 Dec 2018 16:55:39 -0500 Received: from pub.yeoldevic.com ([81.174.156.145] helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1gW730-0002ia-Rk; Sun, 09 Dec 2018 21:55:35 +0000 Received: from ben by deadeye with local (Exim 4.91) (envelope-from ) id 1gW72g-0003Wx-Sw; Sun, 09 Dec 2018 21:55:14 +0000 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, "Sven Eckelmann" , "Simon Wunderlich" , "Marek Lindner" Date: Sun, 09 Dec 2018 21:50:33 +0000 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 217/328] batman-adv: Place kref_get for softif_vlan near use In-Reply-To: X-SA-Exim-Connect-IP: 81.174.156.145 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 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.62-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Sven Eckelmann commit df28ca6bb3282a4c8dc5b65f60b0136fc190ee52 upstream. It is hard to understand why the refcnt is increased when it isn't done near the actual place the new reference is used. So using kref_get right before the place which requires the reference and in the same function helps to avoid accidental problems caused by incorrect reference counting. Signed-off-by: Sven Eckelmann Signed-off-by: Marek Lindner Signed-off-by: Simon Wunderlich [bwh: Backported to 3.16: - s/kref_get/atomic_inc/ - s/_put/_free_ref/] Signed-off-by: Ben Hutchings --- net/batman-adv/soft-interface.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/batman-adv/soft-interface.c +++ b/net/batman-adv/soft-interface.c @@ -529,6 +529,7 @@ int batadv_softif_create_vlan(struct bat } spin_lock_bh(&bat_priv->softif_vlan_list_lock); + atomic_inc(&vlan->refcount); hlist_add_head_rcu(&vlan->list, &bat_priv->softif_vlan_list); spin_unlock_bh(&bat_priv->softif_vlan_list_lock); @@ -539,6 +540,9 @@ int batadv_softif_create_vlan(struct bat bat_priv->soft_iface->dev_addr, vid, BATADV_NULL_IFINDEX, BATADV_NO_MARK); + /* don't return reference to new softif_vlan */ + batadv_softif_vlan_free_ref(vlan); + return 0; }