Patch "mptcp: deduplicate error paths on endpoint creation" has been added to the 6.1-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    mptcp: deduplicate error paths on endpoint creation

to the 6.1-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     mptcp-deduplicate-error-paths-on-endpoint-creation.patch
and it can be found in the queue-6.1 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit 6f43b15f59b848769b112e2058f7d0c647135afe
Author: Paolo Abeni <pabeni@xxxxxxxxxx>
Date:   Fri Nov 18 10:46:07 2022 -0800

    mptcp: deduplicate error paths on endpoint creation
    
    [ Upstream commit 976d302fb6165ad620778d7ba834cde6e3fe9f9f ]
    
    When endpoint creation fails, we need to free the newly allocated
    entry and eventually destroy the paired mptcp listener socket.
    
    Consolidate such action in a single point let all the errors path
    reach it.
    
    Reviewed-by: Mat Martineau <mathew.j.martineau@xxxxxxxxxxxxxxx>
    Signed-off-by: Paolo Abeni <pabeni@xxxxxxxxxx>
    Signed-off-by: Mat Martineau <mathew.j.martineau@xxxxxxxxxxxxxxx>
    Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
    Stable-dep-of: ad2171009d96 ("mptcp: fix locking for in-kernel listener creation")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/mptcp/pm_netlink.c b/net/mptcp/pm_netlink.c
index 9813ed0fde9bd..fdf2ee29f7623 100644
--- a/net/mptcp/pm_netlink.c
+++ b/net/mptcp/pm_netlink.c
@@ -1003,16 +1003,12 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
 		return err;
 
 	msk = mptcp_sk(entry->lsk->sk);
-	if (!msk) {
-		err = -EINVAL;
-		goto out;
-	}
+	if (!msk)
+		return -EINVAL;
 
 	ssock = __mptcp_nmpc_socket(msk);
-	if (!ssock) {
-		err = -EINVAL;
-		goto out;
-	}
+	if (!ssock)
+		return -EINVAL;
 
 	mptcp_info2sockaddr(&entry->addr, &addr, entry->addr.family);
 #if IS_ENABLED(CONFIG_MPTCP_IPV6)
@@ -1022,20 +1018,16 @@ static int mptcp_pm_nl_create_listen_socket(struct sock *sk,
 	err = kernel_bind(ssock, (struct sockaddr *)&addr, addrlen);
 	if (err) {
 		pr_warn("kernel_bind error, err=%d", err);
-		goto out;
+		return err;
 	}
 
 	err = kernel_listen(ssock, backlog);
 	if (err) {
 		pr_warn("kernel_listen error, err=%d", err);
-		goto out;
+		return err;
 	}
 
 	return 0;
-
-out:
-	sock_release(entry->lsk);
-	return err;
 }
 
 int mptcp_pm_nl_get_local_id(struct mptcp_sock *msk, struct sock_common *skc)
@@ -1327,7 +1319,7 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
 		return -EINVAL;
 	}
 
-	entry = kmalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT);
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL_ACCOUNT);
 	if (!entry) {
 		GENL_SET_ERR_MSG(info, "can't allocate addr");
 		return -ENOMEM;
@@ -1338,22 +1330,21 @@ static int mptcp_nl_cmd_add_addr(struct sk_buff *skb, struct genl_info *info)
 		ret = mptcp_pm_nl_create_listen_socket(skb->sk, entry);
 		if (ret) {
 			GENL_SET_ERR_MSG(info, "create listen socket error");
-			kfree(entry);
-			return ret;
+			goto out_free;
 		}
 	}
 	ret = mptcp_pm_nl_append_new_local_addr(pernet, entry);
 	if (ret < 0) {
 		GENL_SET_ERR_MSG(info, "too many addresses or duplicate one");
-		if (entry->lsk)
-			sock_release(entry->lsk);
-		kfree(entry);
-		return ret;
+		goto out_free;
 	}
 
 	mptcp_nl_add_subflow_or_signal_addr(sock_net(skb->sk));
-
 	return 0;
+
+out_free:
+	__mptcp_pm_release_addr_entry(entry);
+	return ret;
 }
 
 int mptcp_pm_get_flags_and_ifindex_by_id(struct mptcp_sock *msk, unsigned int id,