From 78004e9a87f240df03e2f73120d291763c32e0a7 Mon Sep 17 00:00:00 2001 From: Ali Ahmet Memis Date: Fri, 21 Aug 2026 01:45:27 +0000 Subject: openrisc: fix arbitrary kernel memory access via or1k_atomic syscall sys_or1k_atomic() (syscall 244 in the "or1k" ABI) takes two user pointers, v1 and v2, and swaps the words they point to in hand-written assembly. l.lwz r29,0(r4) l.lwz r27,0(r5) l.sw 0(r4),r27 l.sw 0(r5),r29 The pointers are not checked with access_ok(). The four memory accesses also have no exception table entries. A caller passes a kernel address as either pointer, and the syscall reads from and writes to it directly. This gives an unprivileged process a kernel read/write primitive. It overwrites kernel data such as the sys_call_table, gaining code execution in kernel context. Check both pointers before entering the critical section. Add fixups for the four memory accesses so faults on valid but unmapped user addresses return -EFAULT. [shorne@gmail.com: fix comment style] Fixes: 9d02a4283e9c ("OpenRISC: Boot code") Cc: stable@vger.kernel.org Signed-off-by: Ali Ahmet Memis Signed-off-by: Stafford Horne --- include/rdma/ib_sysfs.h | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) create mode 100644 include/rdma/ib_sysfs.h (limited to 'include/rdma/ib_sysfs.h') diff --git a/include/rdma/ib_sysfs.h b/include/rdma/ib_sysfs.h new file mode 100644 index 000000000..3b77cfd74 --- /dev/null +++ b/include/rdma/ib_sysfs.h @@ -0,0 +1,37 @@ +/* SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause */ +/* + * Copyright (c) 2021 Mellanox Technologies Ltd. All rights reserved. + */ +#ifndef DEF_RDMA_IB_SYSFS_H +#define DEF_RDMA_IB_SYSFS_H + +#include + +struct ib_device; + +struct ib_port_attribute { + struct attribute attr; + ssize_t (*show)(struct ib_device *ibdev, u32 port_num, + struct ib_port_attribute *attr, char *buf); + ssize_t (*store)(struct ib_device *ibdev, u32 port_num, + struct ib_port_attribute *attr, const char *buf, + size_t count); +}; + +#define IB_PORT_ATTR_RW(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_RW(_name) + +#define IB_PORT_ATTR_ADMIN_RW(_name) \ + struct ib_port_attribute ib_port_attr_##_name = \ + __ATTR_RW_MODE(_name, 0600) + +#define IB_PORT_ATTR_RO(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_RO(_name) + +#define IB_PORT_ATTR_WO(_name) \ + struct ib_port_attribute ib_port_attr_##_name = __ATTR_WO(_name) + +struct ib_device *ib_port_sysfs_get_ibdev_kobj(struct kobject *kobj, + u32 *port_num); + +#endif -- cgit v1.3.1