From patchwork Fri Apr 1 15:39:39 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Florent Fourcot X-Patchwork-Id: 12798474 X-Patchwork-Delegate: kuba@kernel.org Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id C0D05C433F5 for ; Fri, 1 Apr 2022 16:15:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239892AbiDAQRQ (ORCPT ); Fri, 1 Apr 2022 12:17:16 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S240237AbiDAQQx (ORCPT ); Fri, 1 Apr 2022 12:16:53 -0400 Received: from olfflo.fourcot.fr (fourcot.fr [217.70.191.14]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2742CFFF98 for ; Fri, 1 Apr 2022 08:40:41 -0700 (PDT) From: Florent Fourcot To: netdev@vger.kernel.org Cc: cong.wang@bytedance.com, edumazet@google.com, Florent Fourcot , Jiri Pirko , Brian Baboch Subject: [PATCH net v2] rtnetlink: enable alt_ifname for setlink/newlink Date: Fri, 1 Apr 2022 17:39:39 +0200 Message-Id: <20220401153939.19620-1-florent.fourcot@wifirst.fr> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org X-Patchwork-Delegate: kuba@kernel.org buffer called "ifname" given in function rtnl_dev_get is always valid when called by setlink/newlink, but contains only empty string when IFLA_IFNAME is not given. So IFLA_ALT_IFNAME is always ignored This patch fixes rtnl_dev_get function with a remove of ifname argument, and move ifname copy in do_setlink when required Changes in v2: * Remove ifname argument in rtnl_dev_get/do_setlink functions (simplify code) Fixes: 76c9ac0ee878 ("net: rtnetlink: add possibility to use alternative names as message handle") CC: Jiri Pirko Signed-off-by: Florent Fourcot Signed-off-by: Brian Baboch --- net/core/rtnetlink.c | 65 +++++++++++++++++++------------------------- 1 file changed, 28 insertions(+), 37 deletions(-) diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index be443cfc77d4..563fdd997f62 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -2607,17 +2607,23 @@ static int do_set_proto_down(struct net_device *dev, static int do_setlink(const struct sk_buff *skb, struct net_device *dev, struct ifinfomsg *ifm, struct netlink_ext_ack *extack, - struct nlattr **tb, char *ifname, int status) + struct nlattr **tb, int status) { const struct net_device_ops *ops = dev->netdev_ops; + char ifname[IFNAMSIZ]; int err; err = validate_linkmsg(dev, tb, extack); if (err < 0) return err; + if (tb[IFLA_IFNAME]) + nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); + else + ifname[0] = '\0'; + if (tb[IFLA_NET_NS_PID] || tb[IFLA_NET_NS_FD] || tb[IFLA_TARGET_NETNSID]) { - const char *pat = ifname && ifname[0] ? ifname : NULL; + const char *pat = ifname[0] ? ifname : NULL; struct net *net; int new_ifindex; @@ -2974,20 +2980,16 @@ static int do_setlink(const struct sk_buff *skb, static struct net_device *rtnl_dev_get(struct net *net, struct nlattr *ifname_attr, - struct nlattr *altifname_attr, - char *ifname) + struct nlattr *altifname_attr) { - char buffer[ALTIFNAMSIZ]; + char ifname[ALTIFNAMSIZ]; - if (!ifname) { - ifname = buffer; - if (ifname_attr) - nla_strscpy(ifname, ifname_attr, IFNAMSIZ); - else if (altifname_attr) - nla_strscpy(ifname, altifname_attr, ALTIFNAMSIZ); - else - return NULL; - } + if (ifname_attr) + nla_strscpy(ifname, ifname_attr, IFNAMSIZ); + else if (altifname_attr) + nla_strscpy(ifname, altifname_attr, ALTIFNAMSIZ); + else + return NULL; return __dev_get_by_name(net, ifname); } @@ -3000,7 +3002,6 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, struct net_device *dev; int err; struct nlattr *tb[IFLA_MAX+1]; - char ifname[IFNAMSIZ]; err = nlmsg_parse_deprecated(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy, extack); @@ -3011,17 +3012,12 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, if (err < 0) goto errout; - if (tb[IFLA_IFNAME]) - nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); - else - ifname[0] = '\0'; - err = -EINVAL; ifm = nlmsg_data(nlh); if (ifm->ifi_index > 0) dev = __dev_get_by_index(net, ifm->ifi_index); else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) - dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname); + dev = rtnl_dev_get(net, tb[IFLA_IFNAME], tb[IFLA_ALT_IFNAME]); else goto errout; @@ -3030,7 +3026,7 @@ static int rtnl_setlink(struct sk_buff *skb, struct nlmsghdr *nlh, goto errout; } - err = do_setlink(skb, dev, ifm, extack, tb, ifname, 0); + err = do_setlink(skb, dev, ifm, extack, tb, 0); errout: return err; } @@ -3119,8 +3115,7 @@ static int rtnl_dellink(struct sk_buff *skb, struct nlmsghdr *nlh, if (ifm->ifi_index > 0) dev = __dev_get_by_index(tgt_net, ifm->ifi_index); else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) - dev = rtnl_dev_get(net, tb[IFLA_IFNAME], - tb[IFLA_ALT_IFNAME], NULL); + dev = rtnl_dev_get(net, tb[IFLA_IFNAME], tb[IFLA_ALT_IFNAME]); else if (tb[IFLA_GROUP]) err = rtnl_group_dellink(tgt_net, nla_get_u32(tb[IFLA_GROUP])); else @@ -3262,7 +3257,7 @@ static int rtnl_group_changelink(const struct sk_buff *skb, for_each_netdev_safe(net, dev, aux) { if (dev->group == group) { - err = do_setlink(skb, dev, ifm, extack, tb, NULL, 0); + err = do_setlink(skb, dev, ifm, extack, tb, 0); if (err < 0) return err; } @@ -3303,16 +3298,11 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, if (err < 0) return err; - if (tb[IFLA_IFNAME]) - nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); - else - ifname[0] = '\0'; - ifm = nlmsg_data(nlh); if (ifm->ifi_index > 0) dev = __dev_get_by_index(net, ifm->ifi_index); else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) - dev = rtnl_dev_get(net, NULL, tb[IFLA_ALT_IFNAME], ifname); + dev = rtnl_dev_get(net, tb[IFLA_IFNAME], tb[IFLA_ALT_IFNAME]); else dev = NULL; @@ -3413,7 +3403,7 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, status |= DO_SETLINK_NOTIFY; } - return do_setlink(skb, dev, ifm, extack, tb, ifname, status); + return do_setlink(skb, dev, ifm, extack, tb, status); } if (!(nlh->nlmsg_flags & NLM_F_CREATE)) { @@ -3450,7 +3440,10 @@ static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh, if (!ops->alloc && !ops->setup) return -EOPNOTSUPP; - if (!ifname[0]) { + if (tb[IFLA_IFNAME]) { + nla_strscpy(ifname, tb[IFLA_IFNAME], IFNAMSIZ); + } + else { snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind); name_assign_type = NET_NAME_ENUM; } @@ -3622,8 +3615,7 @@ static int rtnl_getlink(struct sk_buff *skb, struct nlmsghdr *nlh, if (ifm->ifi_index > 0) dev = __dev_get_by_index(tgt_net, ifm->ifi_index); else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) - dev = rtnl_dev_get(tgt_net, tb[IFLA_IFNAME], - tb[IFLA_ALT_IFNAME], NULL); + dev = rtnl_dev_get(tgt_net, tb[IFLA_IFNAME], tb[IFLA_ALT_IFNAME]); else goto out; @@ -3718,8 +3710,7 @@ static int rtnl_linkprop(int cmd, struct sk_buff *skb, struct nlmsghdr *nlh, if (ifm->ifi_index > 0) dev = __dev_get_by_index(net, ifm->ifi_index); else if (tb[IFLA_IFNAME] || tb[IFLA_ALT_IFNAME]) - dev = rtnl_dev_get(net, tb[IFLA_IFNAME], - tb[IFLA_ALT_IFNAME], NULL); + dev = rtnl_dev_get(net, tb[IFLA_IFNAME], tb[IFLA_ALT_IFNAME]); else return -EINVAL;