nfsd: minor off by one checks in __write_versions()

My static checker complains that if "len == remaining" then it means we
have truncated the last character off the version string.

The intent of the code is that we print as many versions as we can
without truncating a version.  Then we put a newline at the end.  If the
newline can't fit we return -EINVAL.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: NJeff Layton <jlayton@primarydata.com>
Signed-off-by: NJ. Bruce Fields <bfields@redhat.com>

fs/nfsd/nfsctl.c

@@ -606,7 +606,7 @@ static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 				       num);
 			sep = " ";
 
-			if (len > remaining)
+			if (len >= remaining)
 				break;
 			remaining -= len;
 			buf += len;
@@ -621,7 +621,7 @@ static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 						'+' : '-',
 					minor);
 
-			if (len > remaining)
+			if (len >= remaining)
 				break;
 			remaining -= len;
 			buf += len;
@@ -629,7 +629,7 @@ static ssize_t __write_versions(struct file *file, char *buf, size_t size)
 		}
 
 	len = snprintf(buf, remaining, "\n");
-	if (len > remaining)
+	if (len >= remaining)
 		return -EINVAL;
 	return tlen + len;
 }