mptcp: pm: add remote parameter for set_flags

The remote address of set_flags() interface is useful for userspace PM,
but unused in in-kernel PM.

But an additional "changed" parameter needs to be passed to set_flags() of
in-kernel PM. One option is to add a "u8 changed" parameter to set_flags()
interface:

	set_flags(struct mptcp_pm_addr_entry *local,
		  struct mptcp_addr_info *remote,
		  u8 changed)

A better option is to add a struct mptcp_pm_addr_entry "remote" parameter
for set_flags(), so that "remote->addr" can be used for userspace PM, and
"remote->flags" can be used for in-kernel PM to replace the additional
"changed" parameter.

Signed-off-by: Geliang Tang <[email protected]>

Author: Geliang Tang

net/mptcp/pm.c

@@ -531,7 +531,8 @@ int mptcp_pm_nl_get_addr_dumpit(struct sk_buff *msg,
 static int mptcp_pm_set_flags(struct genl_info *info)
 {
 	struct mptcp_pm_addr_entry loc = { .addr = { .family = AF_UNSPEC }, };
-	struct nlattr *attr_loc;
+	struct mptcp_pm_addr_entry rem = { .addr = { .family = AF_UNSPEC }, };
+	struct nlattr *attr_loc, *attr_rem;
 	int ret = -EINVAL;
 
 	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR))
@@ -542,9 +543,20 @@ static int mptcp_pm_set_flags(struct genl_info *info)
 	if (ret < 0)
 		return ret;
 
-	if (info->attrs[MPTCP_PM_ATTR_TOKEN])
-		return mptcp_userspace_pm_set_flags(&loc, info);
-	return mptcp_pm_nl_set_flags(&loc, info);
+	if (info->attrs[MPTCP_PM_ATTR_TOKEN]) {
+		attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
+		ret = mptcp_pm_parse_entry(attr_rem, info, false, &rem);
+		if (ret < 0)
+			return ret;
+
+		if (rem.addr.family == AF_UNSPEC) {
+			NL_SET_ERR_MSG_ATTR(info->extack, attr_rem,
+					    "invalid remote address family");
+			return -EINVAL;
+		}
+		return mptcp_userspace_pm_set_flags(&loc, &rem, info);
+	}
+	return mptcp_pm_nl_set_flags(&loc, &rem, info);
 }
 
 int mptcp_pm_nl_set_flags_doit(struct sk_buff *skb, struct genl_info *info)

net/mptcp/pm_netlink.c

@@ -1949,6 +1949,7 @@ static void mptcp_nl_set_flags(struct net *net,
 }
 
 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local,
+			  struct mptcp_pm_addr_entry *remote,
 			  struct genl_info *info)
 {
 	struct nlattr *attr = info->attrs[MPTCP_PM_ATTR_ADDR];

net/mptcp/pm_userspace.c

@@ -553,19 +553,16 @@ int mptcp_pm_nl_subflow_destroy_doit(struct sk_buff *skb, struct genl_info *info
 }
 
 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
+				 struct mptcp_pm_addr_entry *remote,
 				 struct genl_info *info)
 {
-	struct mptcp_addr_info rem = { .family = AF_UNSPEC, };
 	struct mptcp_pm_addr_entry *entry;
-	struct nlattr *attr, *attr_rem;
 	struct mptcp_sock *msk;
+	struct nlattr *attr;
 	int ret = -EINVAL;
 	struct sock *sk;
 	u8 bkup = 0;
 
-	if (GENL_REQ_ATTR_CHECK(info, MPTCP_PM_ATTR_ADDR_REMOTE))
-		return ret;
-
 	msk = mptcp_userspace_pm_get_sock(info);
 	if (!msk)
 		return ret;
@@ -580,18 +577,6 @@ int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
 		goto set_flags_err;
 	}
 
-	attr_rem = info->attrs[MPTCP_PM_ATTR_ADDR_REMOTE];
-	ret = mptcp_pm_parse_addr(attr_rem, info, &rem);
-	if (ret < 0)
-		goto set_flags_err;
-
-	if (rem.family == AF_UNSPEC) {
-		NL_SET_ERR_MSG_ATTR(info->extack, attr_rem,
-				    "invalid remote address family");
-		ret = -EINVAL;
-		goto set_flags_err;
-	}
-
 	if (local->flags & MPTCP_PM_ADDR_FLAG_BACKUP)
 		bkup = 1;
 
@@ -606,7 +591,7 @@ int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
 	spin_unlock_bh(&msk->pm.lock);
 
 	lock_sock(sk);
-	ret = mptcp_pm_nl_mp_prio_send_ack(msk, &local->addr, &rem, bkup);
+	ret = mptcp_pm_nl_mp_prio_send_ack(msk, &local->addr, &remote->addr, bkup);
 	release_sock(sk);
 
 	/* mptcp_pm_nl_mp_prio_send_ack() only fails in one case */

net/mptcp/protocol.h

@@ -1038,8 +1038,10 @@ bool mptcp_lookup_subflow_by_saddr(const struct list_head *list,
 bool mptcp_remove_anno_list_by_saddr(struct mptcp_sock *msk,
 				     const struct mptcp_addr_info *addr);
 int mptcp_pm_nl_set_flags(struct mptcp_pm_addr_entry *local,
+			  struct mptcp_pm_addr_entry *remote,
 			  struct genl_info *info);
 int mptcp_userspace_pm_set_flags(struct mptcp_pm_addr_entry *local,
+				 struct mptcp_pm_addr_entry *remote,
 				 struct genl_info *info);
 int mptcp_pm_announce_addr(struct mptcp_sock *msk,
 			   const struct mptcp_addr_info *addr,