[PATCH] knfsd: nfsd4: fix non-terminated string

The server name is expected to be a null-terminated string, so we can't pass
in the raw client identifier.

What's more, the client identifier is just a binary, not necessarily
printable, blob.  Let's just use the ip address instead.  The server name
appears to exist just to help debugging by making some printk's more
informative.

Note that the string is copies into the rpc client structure, so the pointer
to the local variable does not outlive the function call.
Signed-off-by: N"J. Bruce Fields" <bfields@citi.umich.edu>
Signed-off-by: NNeil Brown <neilb@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/nfsd/nfs4callback.c

@@ -387,7 +387,6 @@ nfsd4_probe_callback(struct nfs4_client *clp)
 		.address	= (struct sockaddr *)&addr,
 		.addrsize	= sizeof(addr),
 		.timeout	= &timeparms,
-		.servername	= clp->cl_name.data,
 		.program	= program,
 		.version	= nfs_cb_version[1]->number,
 		.authflavor	= RPC_AUTH_UNIX,	/* XXX: need AUTH_GSS... */
@@ -397,6 +396,7 @@ nfsd4_probe_callback(struct nfs4_client *clp)
 		.rpc_proc       = &nfs4_cb_procedures[NFSPROC4_CLNT_CB_NULL],
 		.rpc_argp       = clp,
 	};
+	char clientname[16];
 	int status;
 
 	if (atomic_read(&cb->cb_set))
@@ -419,6 +419,11 @@ nfsd4_probe_callback(struct nfs4_client *clp)
 	memset(program->stats, 0, sizeof(cb->cb_stat));
 	program->stats->program = program;
 
+	/* Just here to make some printk's more useful: */
+	snprintf(clientname, sizeof(clientname),
+		"%u.%u.%u.%u", NIPQUAD(addr.sin_addr));
+	args.servername = clientname;
+
 	/* Create RPC client */
 	cb->cb_client = rpc_create(&args);
 	if (IS_ERR(cb->cb_client)) {