From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [PATCH net] rtnetlink: NUL-terminate IFLA_PHYS_PORT_NAME string Date: Thu, 4 May 2017 10:14:13 -0600 Message-ID: <1df4c5ca-9f8d-3cba-52d0-2efbd4117a69@gmail.com> References: <20170504144858.1905-1-mschmidt@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Cc: Thomas Haller To: Michal Schmidt , netdev@vger.kernel.org Return-path: Received: from mail-pg0-f66.google.com ([74.125.83.66]:33334 "EHLO mail-pg0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754489AbdEDQOQ (ORCPT ); Thu, 4 May 2017 12:14:16 -0400 Received: by mail-pg0-f66.google.com with SMTP id s62so2890569pgc.0 for ; Thu, 04 May 2017 09:14:16 -0700 (PDT) In-Reply-To: <20170504144858.1905-1-mschmidt@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On 5/4/17 8:48 AM, Michal Schmidt wrote: > IFLA_PHYS_PORT_NAME is a string attribute, so terminate it with \0. > Otherwise libnl3 fails to validate netlink messages with this attribute. > "ip -detail a" assumes too that the attribute is NUL-terminated when > printing it. It often was, due to padding. > > I noticed this as libvirtd failing to start on a system with sfc driver > after upgrading it to Linux 4.11, i.e. when sfc added support for > phys_port_name. > > Signed-off-by: Michal Schmidt > --- > net/core/rtnetlink.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c > index c4e84c5582..69daf393cb 100644 > --- a/net/core/rtnetlink.c > +++ b/net/core/rtnetlink.c > @@ -1056,7 +1056,7 @@ static int rtnl_phys_port_name_fill(struct sk_buff *skb, struct net_device *dev) > return err; > } > > - if (nla_put(skb, IFLA_PHYS_PORT_NAME, strlen(name), name)) > + if (nla_put_string(skb, IFLA_PHYS_PORT_NAME, name)) > return -EMSGSIZE; > > return 0; > Thanks for fixing.