diff mbox series

[v1,net-next,09/13] rtnetlink: Fetch IFLA_LINK_NETNSID in rtnl_newlink().

Message ID 20241009231656.57830-10-kuniyu@amazon.com (mailing list archive)
State Superseded
Delegated to: Netdev Maintainers
Headers show
Series rtnetlink: Refactor rtnl_{new,del,set}link() for per-netns RTNL. | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 6 this patch: 6
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers success CCed 5 of 5 maintainers
netdev/build_clang success Errors and warnings before: 6 this patch: 6
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success Found: 'put_net(' was: 1 now: 1
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 7 this patch: 7
netdev/checkpatch warning WARNING: line length of 81 exceeds 80 columns WARNING: line length of 82 exceeds 80 columns WARNING: line length of 92 exceeds 80 columns
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 6 this patch: 6
netdev/source_inline success Was 0 now: 0

Commit Message

Kuniyuki Iwashima Oct. 9, 2024, 11:16 p.m. UTC 
Another netns option for RTM_NEWLINK is IFLA_LINK_NETNSID and
is fetched in rtnl_newlink_create().

This must be done before holding rtnl_net_lock().

Let's move IFLA_LINK_NETNSID processing to rtnl_newlink().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
---
 net/core/rtnetlink.c | 49 ++++++++++++++++++++++----------------------
 1 file changed, 24 insertions(+), 25 deletions(-)

Comments

Eric Dumazet Oct. 10, 2024, 1:09 p.m. UTC | #1 
On Thu, Oct 10, 2024 at 1:20 AM Kuniyuki Iwashima <kuniyu@amazon.com> wrote:
>
> Another netns option for RTM_NEWLINK is IFLA_LINK_NETNSID and
> is fetched in rtnl_newlink_create().
>
> This must be done before holding rtnl_net_lock().
>
> Let's move IFLA_LINK_NETNSID processing to rtnl_newlink().
>
> Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>

Reviewed-by: Eric Dumazet <edumazet@google.com>
diff mbox series

Patch

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c
index fc62f23d2647..70a3a9f411d8 100644
--- a/net/core/rtnetlink.c
+++ b/net/core/rtnetlink.c
@@ -3628,7 +3628,7 @@  static int rtnl_group_changelink(const struct sk_buff *skb,
 
 static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 			       const struct rtnl_link_ops *ops,
-			       struct net *tgt_net,
+			       struct net *tgt_net, struct net *link_net,
 			       const struct nlmsghdr *nlh,
 			       struct nlattr **tb, struct nlattr **data,
 			       struct netlink_ext_ack *extack)
@@ -3638,7 +3638,6 @@  static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 	u32 portid = NETLINK_CB(skb).portid;
 	struct net_device *dev;
 	char ifname[IFNAMSIZ];
-	struct net *link_net;
 	int err;
 
 	if (!ops->alloc && !ops->setup)
@@ -3651,22 +3650,6 @@  static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 		name_assign_type = NET_NAME_ENUM;
 	}
 
-	if (tb[IFLA_LINK_NETNSID]) {
-		int id = nla_get_s32(tb[IFLA_LINK_NETNSID]);
-
-		link_net = get_net_ns_by_id(tgt_net, id);
-		if (!link_net) {
-			NL_SET_ERR_MSG(extack, "Unknown network namespace id");
-			err =  -EINVAL;
-			goto out;
-		}
-		err = -EPERM;
-		if (!netlink_ns_capable(skb, link_net->user_ns, CAP_NET_ADMIN))
-			goto out;
-	} else {
-		link_net = NULL;
-	}
-
 	dev = rtnl_create_link(link_net ? : tgt_net, ifname,
 			       name_assign_type, ops, tb, extack);
 	if (IS_ERR(dev)) {
@@ -3699,9 +3682,6 @@  static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 			goto out_unregister;
 	}
 out:
-	if (link_net)
-		put_net(link_net);
-
 	return err;
 out_unregister:
 	if (ops->newlink) {
@@ -3717,7 +3697,7 @@  static int rtnl_newlink_create(struct sk_buff *skb, struct ifinfomsg *ifm,
 
 static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 			  const struct rtnl_link_ops *ops,
-			  struct net *tgt_net,
+			  struct net *tgt_net, struct net *link_net,
 			  struct rtnl_newlink_tbs *tbs,
 			  struct nlattr **data,
 			  struct netlink_ext_ack *extack)
@@ -3766,16 +3746,16 @@  static int __rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 		return -EOPNOTSUPP;
 	}
 
-	return rtnl_newlink_create(skb, ifm, ops, tgt_net, nlh, tb, data, extack);
+	return rtnl_newlink_create(skb, ifm, ops, tgt_net, link_net, nlh, tb, data, extack);
 }
 
 static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 			struct netlink_ext_ack *extack)
 {
 	struct nlattr **tb, **linkinfo, **data = NULL;
+	struct net *tgt_net, *link_net = NULL;
 	struct rtnl_link_ops *ops = NULL;
 	struct rtnl_newlink_tbs *tbs;
-	struct net *tgt_net;
 	int ops_srcu_index;
 	int ret;
 
@@ -3846,8 +3826,27 @@  static int rtnl_newlink(struct sk_buff *skb, struct nlmsghdr *nlh,
 		goto put_ops;
 	}
 
-	ret = __rtnl_newlink(skb, nlh, ops, tgt_net, tbs, data, extack);
+	if (tb[IFLA_LINK_NETNSID]) {
+		int id = nla_get_s32(tb[IFLA_LINK_NETNSID]);
+
+		link_net = get_net_ns_by_id(tgt_net, id);
+		if (!link_net) {
+			NL_SET_ERR_MSG(extack, "Unknown network namespace id");
+			ret =  -EINVAL;
+			goto put_net;
+		}
+
+		if (!netlink_ns_capable(skb, link_net->user_ns, CAP_NET_ADMIN)) {
+			ret = -EPERM;
+			goto put_net;
+		}
+	}
+
+	ret = __rtnl_newlink(skb, nlh, ops, tgt_net, link_net, tbs, data, extack);
 
+put_net:
+	if (link_net)
+		put_net(link_net);
 	put_net(tgt_net);
 put_ops:
 	if (ops)