1 files changed, 23 insertions, 31 deletions

diff --git a/include/rdma/ib.h b/include/rdma/ib.h
index cf8f9e700e48..f7c185ff7a11 100644
--- a/include/rdma/ib.h
+++ b/include/rdma/ib.h
@@ -1,39 +1,16 @@
+/* SPDX-License-Identifier: GPL-2.0 OR Linux-OpenIB */
 /*
  * Copyright (c) 2010 Intel Corporation.  All rights reserved.
- *
- * This software is available to you under a choice of one of two
- * licenses.  You may choose to be licensed under the terms of the GNU
- * General Public License (GPL) Version 2, available from the file
- * COPYING in the main directory of this source tree, or the
- * OpenIB.org BSD license below:
- *
- *     Redistribution and use in source and binary forms, with or
- *     without modification, are permitted provided that the following
- *     conditions are met:
- *
- *      - Redistributions of source code must retain the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer.
- *
- *      - Redistributions in binary form must reproduce the above
- *        copyright notice, this list of conditions and the following
- *        disclaimer in the documentation and/or other materials
- *        provided with the distribution.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
- * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
- * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
- * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
- * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
- * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
- * SOFTWARE.
  */
 
-#if !defined(_RDMA_IB_H)
+#ifndef _RDMA_IB_H
 #define _RDMA_IB_H
 
 #include <linux/types.h>
+#include <linux/sched.h>
+#include <linux/cred.h>
+#include <linux/uaccess.h>
+#include <linux/fs.h>
 
 struct ib_addr {
 	union {
@@ -51,12 +28,12 @@ struct ib_addr {
 #define sib_interface_id	ib_u.uib_addr64[1]
 };
 
-static inline int ib_addr_any(const struct ib_addr *a)
+static inline bool ib_addr_any(const struct ib_addr *a)
 {
 	return ((a->sib_addr64[0] | a->sib_addr64[1]) == 0);
 }
 
-static inline int ib_addr_loopback(const struct ib_addr *a)
+static inline bool ib_addr_loopback(const struct ib_addr *a)
 {
 	return ((a->sib_addr32[0] | a->sib_addr32[1] |
 		 a->sib_addr32[2] | (a->sib_addr32[3] ^ htonl(1))) == 0);
@@ -86,4 +63,19 @@ struct sockaddr_ib {
 	__u64			sib_scope_id;
 };
 
+/*
+ * The IB interfaces that use write() as bi-directional ioctl() are
+ * fundamentally unsafe, since there are lots of ways to trigger "write()"
+ * calls from various contexts with elevated privileges. That includes the
+ * traditional suid executable error message writes, but also various kernel
+ * interfaces that can write to file descriptors.
+ *
+ * This function provides protection for the legacy API by restricting the
+ * calling context.
+ */
+static inline bool ib_safe_file_access(struct file *filp)
+{
+	return filp->f_cred == current_cred();
+}
+
 #endif /* _RDMA_IB_H */