Patch "af_unix: Return an error as a pointer in unix_find_other()." has been added to the 5.15-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

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

    af_unix: Return an error as a pointer in unix_find_other().

to the 5.15-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:
     af_unix-return-an-error-as-a-pointer-in-unix_find_ot.patch
and it can be found in the queue-5.15 subdirectory.

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



commit 8d66d269fbdf2e746bb696f4723f626698608dee
Author: Kuniyuki Iwashima <kuniyu@xxxxxxxxxxxx>
Date:   Wed Nov 24 11:14:22 2021 +0900

    af_unix: Return an error as a pointer in unix_find_other().
    
    [ Upstream commit aed26f557bbc94f0c778f63d7dfe86af99208f68 ]
    
    We can return an error as a pointer and need not pass an additional
    argument to unix_find_other().
    
    Signed-off-by: Kuniyuki Iwashima <kuniyu@xxxxxxxxxxxx>
    Signed-off-by: Jakub Kicinski <kuba@xxxxxxxxxx>
    Stable-dep-of: a9bf9c7dc6a5 ("af_unix: Annotate data-race of sk->sk_state in unix_stream_connect().")
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/net/unix/af_unix.c b/net/unix/af_unix.c
index 20a7be3effe83..0a1258b417a9d 100644
--- a/net/unix/af_unix.c
+++ b/net/unix/af_unix.c
@@ -952,7 +952,7 @@ static int unix_release(struct socket *sock)
 }
 
 static struct sock *unix_find_bsd(struct net *net, struct sockaddr_un *sunaddr,
-				  int type, int *error)
+				  int type)
 {
 	struct inode *inode;
 	struct path path;
@@ -991,23 +991,20 @@ static struct sock *unix_find_bsd(struct net *net, struct sockaddr_un *sunaddr,
 path_put:
 	path_put(&path);
 fail:
-	*error = err;
-	return NULL;
+	return ERR_PTR(err);
 }
 
 static struct sock *unix_find_abstract(struct net *net,
 				       struct sockaddr_un *sunaddr,
 				       int addr_len, int type,
-				       unsigned int hash, int *error)
+				       unsigned int hash)
 {
 	struct dentry *dentry;
 	struct sock *sk;
 
 	sk = unix_find_socket_byname(net, sunaddr, addr_len, type ^ hash);
-	if (!sk) {
-		*error = -ECONNREFUSED;
-		return NULL;
-	}
+	if (!sk)
+		return ERR_PTR(-ECONNREFUSED);
 
 	dentry = unix_sk(sk)->path.dentry;
 	if (dentry)
@@ -1019,15 +1016,14 @@ static struct sock *unix_find_abstract(struct net *net,
 static struct sock *unix_find_other(struct net *net,
 				    struct sockaddr_un *sunaddr,
 				    int addr_len, int type,
-				    unsigned int hash, int *error)
+				    unsigned int hash)
 {
 	struct sock *sk;
 
 	if (sunaddr->sun_path[0])
-		sk = unix_find_bsd(net, sunaddr, type, error);
+		sk = unix_find_bsd(net, sunaddr, type);
 	else
-		sk = unix_find_abstract(net, sunaddr, addr_len, type, hash,
-					error);
+		sk = unix_find_abstract(net, sunaddr, addr_len, type, hash);
 
 	return sk;
 }
@@ -1262,9 +1258,11 @@ static int unix_dgram_connect(struct socket *sock, struct sockaddr *addr,
 		}
 
 restart:
-		other = unix_find_other(net, sunaddr, alen, sock->type, hash, &err);
-		if (!other)
+		other = unix_find_other(net, sunaddr, alen, sock->type, hash);
+		if (IS_ERR(other)) {
+			err = PTR_ERR(other);
 			goto out;
+		}
 
 		unix_state_double_lock(sk, other);
 
@@ -1402,9 +1400,12 @@ static int unix_stream_connect(struct socket *sock, struct sockaddr *uaddr,
 
 restart:
 	/*  Find listening sock. */
-	other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash, &err);
-	if (!other)
+	other = unix_find_other(net, sunaddr, addr_len, sk->sk_type, hash);
+	if (IS_ERR(other)) {
+		err = PTR_ERR(other);
+		other = NULL;
 		goto out;
+	}
 
 	/* Latch state of peer */
 	unix_state_lock(other);
@@ -1873,9 +1874,12 @@ static int unix_dgram_sendmsg(struct socket *sock, struct msghdr *msg,
 			goto out_free;
 
 		other = unix_find_other(net, sunaddr, namelen, sk->sk_type,
-					hash, &err);
-		if (other == NULL)
+					hash);
+		if (IS_ERR(other)) {
+			err = PTR_ERR(other);
+			other = NULL;
 			goto out_free;
+		}
 	}
 
 	if (sk_filter(other, skb) < 0) {