lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Message-ID: <m1hcplt102.fsf@ebiederm.dsl.xmission.com> Date: Wed, 06 Jun 2007 12:02:21 -0600 From: ebiederm@...ssion.com (Eric W. Biederman) To: Patrick McHardy <kaber@...sh.net> Cc: netdev@...r.kernel.org, socketcan@...tkopp.net, hadi@...erus.ca, xemul@...ru, tgraf@...g.ch Subject: Re: [RFC RTNETLINK 04/09]: Link creation API Patrick McHardy <kaber@...sh.net> writes: > Eric W. Biederman wrote: >>>+ if (linkinfo[IFLA_INFO_NAME]) { >>>+ nla_strlcpy(name, linkinfo[IFLA_INFO_NAME], sizeof(name)); >>>+ ops = rtnl_link_ops_get(name); >> >> >> Ugh. Shouldn't we have the request_module logic here? >> Otherwise it looks like we can skip the validate method and >> have other weird interactions. > > > Good catch. The easiest solution seems be to simply replay the > request after successful module load, which also avoids the > device lookup race. Looks reasonable to me. There might be a variable or two that we need to make certain is initialized but at a quick glance it looks ok. Eric > Something like this (untested). > > diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c > index 8d2f817..f2868b0 100644 > --- a/net/core/rtnetlink.c > +++ b/net/core/rtnetlink.c > @@ -930,6 +930,7 @@ static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr > *nlh, void *arg) > struct nlattr *linkinfo[IFLA_INFO_MAX+1]; > int err; > > +replay: > err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFLA_MAX, ifla_policy); > if (err < 0) > return err; > @@ -1012,19 +1013,19 @@ static int rtnl_newlink(struct sk_buff *skb, struct > nlmsghdr *nlh, void *arg) > if (tb[IFLA_ADDRESS] || tb[IFLA_BROADCAST] || tb[IFLA_MAP]) > return -EOPNOTSUPP; > > + if (!ops) { > #ifdef CONFIG_KMOD > - if (!ops && kind[0]) { > - /* race condition: device may be created while rtnl is > - * unlocked, final register_netdevice will catch it. > - */ > - __rtnl_unlock(); > - request_module("rtnl-link-%s", kind); > - rtnl_lock(); > - ops = rtnl_link_ops_get(kind); > - } > + if (kind[0]) { > + __rtnl_unlock(); > + request_module("rtnl-link-%s", kind); > + rtnl_lock(); > + ops = rtnl_link_ops_get(kind); > + if (ops) > + goto replay; > + } > #endif > - if (!ops) > return -EOPNOTSUPP; > + } > > if (!ifname[0]) > snprintf(ifname, IFNAMSIZ, "%s%%d", ops->kind); - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists