From patchwork Wed May 27 23:58:04 2009 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: David Miller X-Patchwork-Id: 27759 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming@bilbo.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from ozlabs.org (ozlabs.org [203.10.76.45]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client CN "mx.ozlabs.org", Issuer "CA Cert Signing Authority" (verified OK)) by bilbo.ozlabs.org (Postfix) with ESMTPS id DC146B707D for ; Thu, 28 May 2009 09:58:52 +1000 (EST) Received: by ozlabs.org (Postfix) id CED69DDFD6; Thu, 28 May 2009 09:58:52 +1000 (EST) Delivered-To: patchwork-incoming@ozlabs.org Received: from vger.kernel.org (vger.kernel.org [209.132.176.167]) by ozlabs.org (Postfix) with ESMTP id 764DBDDFD4 for ; Thu, 28 May 2009 09:58:52 +1000 (EST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756601AbZE0X6H (ORCPT ); Wed, 27 May 2009 19:58:07 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1756792AbZE0X6F (ORCPT ); Wed, 27 May 2009 19:58:05 -0400 Received: from 74-93-104-97-Washington.hfc.comcastbusiness.net ([74.93.104.97]:35729 "EHLO sunset.davemloft.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755042AbZE0X6E (ORCPT ); Wed, 27 May 2009 19:58:04 -0400 Received: from localhost (localhost [127.0.0.1]) by sunset.davemloft.net (Postfix) with ESMTP id 5A50CC8C0F5 for ; Wed, 27 May 2009 16:58:04 -0700 (PDT) Date: Wed, 27 May 2009 16:58:04 -0700 (PDT) Message-Id: <20090527.165804.73643121.davem@davemloft.net> To: netdev@vger.kernel.org Subject: [PATCH]: Fix IP DDP appletalk locking. From: David Miller X-Mailer: Mew version 6.2.51 on Emacs 22.1 / Mule 5.0 (SAKAKI) Mime-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Here is a patch I had sitting around for a year or so. When I was doing the TX multiqueue stuff I noticed that the IPDDP driver did absolutely no locking around it's routing table even though it's accessed concurrently by the ioctls and the transmit path. Added to net-next-2.6 appletalk: Add proper locking around IPDDP routing table. Signed-off-by: David S. Miller --- drivers/net/appletalk/ipddp.c | 40 ++++++++++++++++++++++++++++++++-------- 1 files changed, 32 insertions(+), 8 deletions(-) diff --git a/drivers/net/appletalk/ipddp.c b/drivers/net/appletalk/ipddp.c index f939e92..9832b75 100644 --- a/drivers/net/appletalk/ipddp.c +++ b/drivers/net/appletalk/ipddp.c @@ -39,6 +39,7 @@ static const char version[] = KERN_INFO "ipddp.c:v0.01 8/28/97 Bradford W. Johnson \n"; static struct ipddp_route *ipddp_route_list; +static DEFINE_SPINLOCK(ipddp_route_lock); #ifdef CONFIG_IPDDP_ENCAP static int ipddp_mode = IPDDP_ENCAP; @@ -50,7 +51,7 @@ static int ipddp_mode = IPDDP_DECAP; static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev); static int ipddp_create(struct ipddp_route *new_rt); static int ipddp_delete(struct ipddp_route *rt); -static struct ipddp_route* ipddp_find_route(struct ipddp_route *rt); +static struct ipddp_route* __ipddp_find_route(struct ipddp_route *rt); static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd); static const struct net_device_ops ipddp_netdev_ops = { @@ -119,6 +120,8 @@ static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev) struct ipddp_route *rt; struct atalk_addr *our_addr; + spin_lock(&ipddp_route_lock); + /* * Find appropriate route to use, based only on IP number. */ @@ -127,8 +130,10 @@ static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev) if(rt->ip == paddr) break; } - if(rt == NULL) + if(rt == NULL) { + spin_unlock(&ipddp_route_lock); return 0; + } our_addr = atalk_find_dev_addr(rt->dev); @@ -174,6 +179,8 @@ static int ipddp_xmit(struct sk_buff *skb, struct net_device *dev) if(aarp_send_ddp(rt->dev, skb, &rt->at, NULL) < 0) dev_kfree_skb(skb); + spin_unlock(&ipddp_route_lock); + return 0; } @@ -196,7 +203,9 @@ static int ipddp_create(struct ipddp_route *new_rt) return -ENETUNREACH; } - if (ipddp_find_route(rt)) { + spin_lock_bh(&ipddp_route_lock); + if (__ipddp_find_route(rt)) { + spin_unlock_bh(&ipddp_route_lock); kfree(rt); return -EEXIST; } @@ -204,6 +213,8 @@ static int ipddp_create(struct ipddp_route *new_rt) rt->next = ipddp_route_list; ipddp_route_list = rt; + spin_unlock_bh(&ipddp_route_lock); + return 0; } @@ -216,6 +227,7 @@ static int ipddp_delete(struct ipddp_route *rt) struct ipddp_route **r = &ipddp_route_list; struct ipddp_route *tmp; + spin_lock_bh(&ipddp_route_lock); while((tmp = *r) != NULL) { if(tmp->ip == rt->ip @@ -223,19 +235,21 @@ static int ipddp_delete(struct ipddp_route *rt) && tmp->at.s_node == rt->at.s_node) { *r = tmp->next; + spin_unlock_bh(&ipddp_route_lock); kfree(tmp); return 0; } r = &tmp->next; } + spin_unlock_bh(&ipddp_route_lock); return (-ENOENT); } /* * Find a routing entry, we only return a FULL match */ -static struct ipddp_route* ipddp_find_route(struct ipddp_route *rt) +static struct ipddp_route* __ipddp_find_route(struct ipddp_route *rt) { struct ipddp_route *f; @@ -253,7 +267,7 @@ static struct ipddp_route* ipddp_find_route(struct ipddp_route *rt) static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) { struct ipddp_route __user *rt = ifr->ifr_data; - struct ipddp_route rcp; + struct ipddp_route rcp, rcp2, *rp; if(!capable(CAP_NET_ADMIN)) return -EPERM; @@ -267,9 +281,19 @@ static int ipddp_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd) return (ipddp_create(&rcp)); case SIOCFINDIPDDPRT: - if(copy_to_user(rt, ipddp_find_route(&rcp), sizeof(struct ipddp_route))) - return -EFAULT; - return 0; + spin_lock_bh(&ipddp_route_lock); + rp = __ipddp_find_route(&rcp); + if (rp) + memcpy(&rcp2, rp, sizeof(rcp2)); + spin_unlock_bh(&ipddp_route_lock); + + if (rp) { + if (copy_to_user(rt, &rcp2, + sizeof(struct ipddp_route))) + return -EFAULT; + return 0; + } else + return -ENOENT; case SIOCDELIPDDPRT: return (ipddp_delete(&rcp));