Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757831AbbGGO4t (ORCPT ); Tue, 7 Jul 2015 10:56:49 -0400 Received: from smtp02.citrix.com ([66.165.176.63]:6576 "EHLO SMTP02.CITRIX.COM" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757766AbbGGO4l (ORCPT ); Tue, 7 Jul 2015 10:56:41 -0400 X-IronPort-AV: E=Sophos;i="5.15,424,1432598400"; d="scan'208";a="281773494" From: Julien Grall To: , , , , , , , , , CC: , Julien Grall , Bernhard Thaler , , , , Bob Liu Subject: [PATCH v2] net/bridge: Use __in6_dev_get rather than in6_dev_get in br_validate_ipv6 Date: Tue, 7 Jul 2015 15:55:21 +0100 Message-ID: <1436280921-2795-1-git-send-email-julien.grall@citrix.com> X-Mailer: git-send-email 2.1.4 MIME-Version: 1.0 Content-Type: text/plain X-DLP: MIA2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1996 Lines: 58 The commit efb6de9b4ba0092b2c55f6a52d16294a8a698edd "netfilter: bridge: forward IPv6 fragmented packets" introduced a new function br_validate_ipv6 which take a reference on the inet6 device. Although, the reference is not released at the end. This will result to the impossibility to destroy any netdevice using ipv6 and bridge. It's possible to directly retrieve the inet6 device without taking a reference as all netfilter hooks are protected by rcu_read_lock via nf_hook_slow. Spotted while trying to destroy a Xen guest on the upstream Linux: "unregister_netdevice: waiting for vif1.0 to become free. Usage count = 1" Signed-off-by: Julien Grall Cc: Bernhard Thaler Cc: Pablo Neira Ayuso Cc: fw@strlen.de Cc: ian.campbell@citrix.com Cc: wei.liu2@citrix.com Cc: Bob Liu --- Note that it's impossible to create new guest after this message. I'm not sure if it's normal. Changes in v2: - Don't take a reference to inet6. - This was "net/bridge: Add missing in6_dev_put in br_validate_ipv6" [0] [0] https://lkml.org/lkml/2015/7/3/443 --- net/bridge/br_netfilter_ipv6.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c index 6d12d26..13b7d1e 100644 --- a/net/bridge/br_netfilter_ipv6.c +++ b/net/bridge/br_netfilter_ipv6.c @@ -104,7 +104,7 @@ int br_validate_ipv6(struct sk_buff *skb) { const struct ipv6hdr *hdr; struct net_device *dev = skb->dev; - struct inet6_dev *idev = in6_dev_get(skb->dev); + struct inet6_dev *idev = __in6_dev_get(skb->dev); u32 pkt_len; u8 ip6h_len = sizeof(struct ipv6hdr); -- 2.1.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/