[PATCH 6.6.y] ksmbd: make ksmbd thread names distinct by client IP

[Ferry Meng]

From: Namjae Jeon <linkinjeon@xxxxxxxxxx>

commit 5da92a251e41f824d7e6b4d54d65dcdcfd69fda3 upstream.

[backport needed for 6.6-stable to close a residual
 active_num_conn leak. Commits 787769c8cc50 (upstream 77ffbcac4e56,
 "smb: server: fix leak of active_num_conn in ksmbd_tcp_new_connection()")
 and 97f8d2648ef4 (upstream 6551300dc452, "smb: server: fix
 active_num_conn leak on transport allocation failure") were
 backported to 6.6.y, but upstream 77ffbcac4e56 was built on top
 of this commit, which removes kernel_getpeername() and the
 out_error: label in ksmbd_tcp_new_connection(). Without this
 commit, the kernel_getpeername() failure path still calls
 free_transport(t) and leaks active_num_conn, eventually
 exhausting max_connections until the module is reloaded.]

This patch makes ksmbd thread names distinct by client IP address.

100943 ?        S      0:00 [ksmbd:::ffff:10.177.110.57]
 or
101752 ?        S      0:00 [ksmbd:10.177.110.57]

Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Ferry Meng <mengferry@xxxxxxxxxxxxxxxxx>
---
 fs/smb/server/transport_tcp.c | 39 ++++++++++++-----------------------
 1 file changed, 13 insertions(+), 26 deletions(-)

diff --git a/fs/smb/server/transport_tcp.c b/fs/smb/server/transport_tcp.c
index e55afd0c9bf4..f04aa8c504ff 100644
--- a/fs/smb/server/transport_tcp.c
+++ b/fs/smb/server/transport_tcp.c
@@ -173,17 +173,6 @@ static struct kvec *get_conn_iovec(struct tcp_transport *t, unsigned int nr_segs
 	return new_iov;
 }
 
-static unsigned short ksmbd_tcp_get_port(const struct sockaddr *sa)
-{
-	switch (sa->sa_family) {
-	case AF_INET:
-		return ntohs(((struct sockaddr_in *)sa)->sin_port);
-	case AF_INET6:
-		return ntohs(((struct sockaddr_in6 *)sa)->sin6_port);
-	}
-	return 0;
-}
-
 /**
  * ksmbd_tcp_new_connection() - create a new tcp session on mount
  * @client_sk:	socket associated with new connection
@@ -195,7 +184,6 @@ static unsigned short ksmbd_tcp_get_port(const struct sockaddr *sa)
  */
 static int ksmbd_tcp_new_connection(struct socket *client_sk)
 {
-	struct sockaddr *csin;
 	int rc = 0;
 	struct tcp_transport *t;
 	struct task_struct *handler;
@@ -208,27 +196,26 @@ static int ksmbd_tcp_new_connection(struct socket *client_sk)
 		return -ENOMEM;
 	}
 
-	csin = KSMBD_TCP_PEER_SOCKADDR(KSMBD_TRANS(t)->conn);
-	if (kernel_getpeername(client_sk, csin) < 0) {
-		pr_err("client ip resolution failed\n");
-		rc = -EINVAL;
-		goto out_error;
-	}
-
+#if IS_ENABLED(CONFIG_IPV6)
+	if (client_sk->sk->sk_family == AF_INET6)
+		handler = kthread_run(ksmbd_conn_handler_loop,
+				KSMBD_TRANS(t)->conn, "ksmbd:%pI6c",
+				&KSMBD_TRANS(t)->conn->inet6_addr);
+	else
+		handler = kthread_run(ksmbd_conn_handler_loop,
+				KSMBD_TRANS(t)->conn, "ksmbd:%pI4",
+				&KSMBD_TRANS(t)->conn->inet_addr);
+#else
 	handler = kthread_run(ksmbd_conn_handler_loop,
-			      KSMBD_TRANS(t)->conn,
-			      "ksmbd:%u",
-			      ksmbd_tcp_get_port(csin));
+			KSMBD_TRANS(t)->conn, "ksmbd:%pI4",
+			&KSMBD_TRANS(t)->conn->inet_addr);
+#endif
 	if (IS_ERR(handler)) {
 		pr_err("cannot start conn thread\n");
 		rc = PTR_ERR(handler);
 		ksmbd_tcp_disconnect(KSMBD_TRANS(t));
 	}
 	return rc;
-
-out_error:
-	free_transport(t);
-	return rc;
 }
 
 /**
-- 
2.43.5