This patch adds a new helper mptcp_userspace_pm_get_entry() to find out
the address entry on the userspace_pm_local_addr_list through the given
address. Use this helper in mptcp_userspace_pm_delete_local_addr() and
mptcp_nl_cmd_sf_destroy().

Signed-off-by: Geliang Tang <geliang.tang@suse.com>
---
 net/mptcp/pm_userspace.c | 43 ++++++++++++++++++++++++++--------------
 1 file changed, 28 insertions(+), 15 deletions(-)

diff --git a/net/mptcp/pm_userspace.c b/net/mptcp/pm_userspace.c
index c1dac6d0a28e..75c08375f6f4 100644
--- a/net/mptcp/pm_userspace.c
+++ b/net/mptcp/pm_userspace.c
@@ -80,6 +80,19 @@ static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
 	return ret;
 }
 
+static struct mptcp_pm_addr_entry *mptcp_userspace_pm_get_entry(struct mptcp_sock *msk,
+								struct mptcp_addr_info *addr)
+{
+	struct mptcp_pm_addr_entry *entry, *tmp;
+
+	list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) {
+		if (mptcp_addresses_equal(&entry->addr, addr, false))
+			return entry;
+	}
+
+	return NULL;
+}
+
 /* If the subflow is closed from the other peer (not via a
  * subflow destroy command then), we want to keep the entry
  * not to assign the same ID to another address and to be
@@ -88,21 +101,19 @@ static int mptcp_userspace_pm_append_new_local_addr(struct mptcp_sock *msk,
 static int mptcp_userspace_pm_delete_local_addr(struct mptcp_sock *msk,
 						struct mptcp_pm_addr_entry *addr)
 {
-	struct mptcp_pm_addr_entry *entry, *tmp;
+	struct mptcp_pm_addr_entry *entry;
 
-	list_for_each_entry_safe(entry, tmp, &msk->pm.userspace_pm_local_addr_list, list) {
-		if (mptcp_addresses_equal(&entry->addr, &addr->addr, false)) {
-			/* TODO: a refcount is needed because the entry can
-			 * be used multiple times (e.g. fullmesh mode).
-			 */
-			list_del_rcu(&entry->list);
-			kfree(entry);
-			msk->pm.local_addr_used--;
-			return 0;
-		}
-	}
+	entry = mptcp_userspace_pm_get_entry(msk, &addr->addr);
+	if (!entry)
+		return -EINVAL;
 
-	return -EINVAL;
+	/* TODO: a refcount is needed because the entry can
+	 * be used multiple times (e.g. fullmesh mode).
+	 */
+	list_del_rcu(&entry->list);
+	kfree(entry);
+	msk->pm.local_addr_used--;
+	return 0;
 }
 
 int mptcp_userspace_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk,
@@ -495,10 +506,12 @@ int mptcp_nl_cmd_sf_destroy(struct sk_buff *skb, struct genl_info *info)
 	ssk = mptcp_nl_find_ssk(msk, &addr_l, &addr_r);
 	if (ssk) {
 		struct mptcp_subflow_context *subflow = mptcp_subflow_ctx(ssk);
-		struct mptcp_pm_addr_entry entry = { .addr = addr_l };
+		struct mptcp_pm_addr_entry *entry;
 
 		spin_lock_bh(&msk->pm.lock);
-		mptcp_userspace_pm_delete_local_addr(msk, &entry);
+		entry = mptcp_userspace_pm_get_entry(msk, &addr_l);
+		if (entry)
+			mptcp_userspace_pm_delete_local_addr(msk, entry);
 		spin_unlock_bh(&msk->pm.lock);
 		mptcp_subflow_shutdown(sk, ssk, RCV_SHUTDOWN | SEND_SHUTDOWN);
 		mptcp_close_ssk(sk, ssk, subflow);
-- 
2.35.3