SUNRPC: Fix error handling in svc_setup_socket()

Dan points out that sock_alloc_file() releases @sock on error, but
so do all of svc_setup_socket's callers, resulting in a double-
release if sock_alloc_file() returns an error.

Rather than allocating a struct file for all new sockets, allocate
one only for sockets created during a TCP accept. For the moment,
those are the only ones that will ever be used with RPC-with-TLS.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: ae0d77708aae ("SUNRPC: Ensure server-side sockets have a sock->file")
Signed-off-by: Chuck Lever <chuck.lever@oracle.com>

diff --git a/net/sunrpc/svcsock.c b/net/sunrpc/svcsock.c
index a51c9b989d58a784edf712d6f560e5c0983b7fb1..9989194446a5433435a109da96feec38d574ed34 100644 (file)
--- a/net/sunrpc/svcsock.c
+++ b/net/sunrpc/svcsock.c
@@ -895,6 +895,9 @@ static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
                trace_svcsock_accept_err(xprt, serv->sv_name, err);
                return NULL;
        }
+       if (IS_ERR(sock_alloc_file(newsock, O_NONBLOCK, NULL)))
+               return NULL;
+
        set_bit(XPT_CONN, &svsk->sk_xprt.xpt_flags);
 
        err = kernel_getpeername(newsock, sin);
@@ -935,7 +938,7 @@ static struct svc_xprt *svc_tcp_accept(struct svc_xprt *xprt)
        return &newsvsk->sk_xprt;
 
 failed:
-       sock_release(newsock);
+       sockfd_put(newsock);
        return NULL;
 }
 
@@ -1430,7 +1433,6 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
                                                struct socket *sock,
                                                int flags)
 {
-       struct file     *filp = NULL;
        struct svc_sock *svsk;
        struct sock     *inet;
        int             pmap_register = !(flags & SVC_SOCK_ANONYMOUS);
@@ -1439,14 +1441,6 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
        if (!svsk)
                return ERR_PTR(-ENOMEM);
 
-       if (!sock->file) {
-               filp = sock_alloc_file(sock, O_NONBLOCK, NULL);
-               if (IS_ERR(filp)) {
-                       kfree(svsk);
-                       return ERR_CAST(filp);
-               }
-       }
-
        inet = sock->sk;
 
        if (pmap_register) {
@@ -1456,8 +1450,6 @@ static struct svc_sock *svc_setup_socket(struct svc_serv *serv,
                                     inet->sk_protocol,
                                     ntohs(inet_sk(inet)->inet_sport));
                if (err < 0) {
-                       if (filp)
-                               fput(filp);
                        kfree(svsk);
                        return ERR_PTR(err);
                }