From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lance Richardson Subject: [PATCH net] vxlan: eliminate cached dst leak Date: Mon, 29 May 2017 13:25:57 -0400 Message-ID: <20170529172557.7065-1-lrichard@redhat.com> To: netdev@vger.kernel.org, pabeni@redhat.com Return-path: Received: from mx1.redhat.com ([209.132.183.28]:54576 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750864AbdE2R0F (ORCPT ); Mon, 29 May 2017 13:26:05 -0400 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id E794180C05 for ; Mon, 29 May 2017 17:26:04 +0000 (UTC) Sender: netdev-owner@vger.kernel.org List-ID: After commit 0c1d70af924b ("net: use dst_cache for vxlan device"), cached dst entries could be leaked when more than one remote was present for a given vxlan_fdb entry, causing subsequent netns operations to block indefinitely and "unregister_netdevice: waiting for lo to become free." messages to appear in the kernel log. Fix by properly releasing cached dst and freeing resources in this case. Fixes: commit 0c1d70af924b ("net: use dst_cache for vxlan device") Signed-off-by: Lance Richardson --- drivers/net/vxlan.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-) diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c index 328b471..5c1d69e 100644 --- a/drivers/net/vxlan.c +++ b/drivers/net/vxlan.c @@ -740,6 +740,22 @@ static void vxlan_fdb_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f) call_rcu(&f->rcu, vxlan_fdb_free); } +static void vxlan_dst_free(struct rcu_head *head) +{ + struct vxlan_rdst *rd = container_of(head, struct vxlan_rdst, rcu); + + dst_cache_destroy(&rd->dst_cache); + kfree(rd); +} + +static void vxlan_fdb_dst_destroy(struct vxlan_dev *vxlan, struct vxlan_fdb *f, + struct vxlan_rdst *rd) +{ + list_del_rcu(&rd->list); + vxlan_fdb_notify(vxlan, f, rd, RTM_DELNEIGH); + call_rcu(&rd->rcu, vxlan_dst_free); +} + static int vxlan_fdb_parse(struct nlattr *tb[], struct vxlan_dev *vxlan, union vxlan_addr *ip, __be16 *port, __be32 *src_vni, __be32 *vni, u32 *ifindex) @@ -864,9 +880,7 @@ static int __vxlan_fdb_delete(struct vxlan_dev *vxlan, * otherwise destroy the fdb entry */ if (rd && !list_is_singular(&f->remotes)) { - list_del_rcu(&rd->list); - vxlan_fdb_notify(vxlan, f, rd, RTM_DELNEIGH); - kfree_rcu(rd, rcu); + vxlan_fdb_dst_destroy(vxlan, f, rd); goto out; } -- 2.7.4