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 --- drivers/interconnect/internal.h | 47 +++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 drivers/interconnect/internal.h (limited to 'drivers/interconnect/internal.h') diff --git a/drivers/interconnect/internal.h b/drivers/interconnect/internal.h new file mode 100644 index 000000000..3b9d50589 --- /dev/null +++ b/drivers/interconnect/internal.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Interconnect framework internal structs + * + * Copyright (c) 2019, Linaro Ltd. + * Author: Georgi Djakov + */ + +#ifndef __DRIVERS_INTERCONNECT_INTERNAL_H +#define __DRIVERS_INTERCONNECT_INTERNAL_H + +/** + * struct icc_req - constraints that are attached to each node + * @req_node: entry in list of requests for the particular @node + * @node: the interconnect node to which this constraint applies + * @dev: reference to the device that sets the constraints + * @enabled: indicates whether the path with this request is enabled + * @tag: path tag (optional) + * @avg_bw: an integer describing the average bandwidth in kBps + * @peak_bw: an integer describing the peak bandwidth in kBps + */ +struct icc_req { + struct hlist_node req_node; + struct icc_node *node; + struct device *dev; + bool enabled; + u32 tag; + u32 avg_bw; + u32 peak_bw; +}; + +/** + * struct icc_path - interconnect path structure + * @name: a string name of the path (useful for ftrace) + * @num_nodes: number of hops (nodes) + * @reqs: array of the requests applicable to this path of nodes + */ +struct icc_path { + const char *name; + size_t num_nodes; + struct icc_req reqs[] __counted_by(num_nodes); +}; + +struct icc_path *icc_get(struct device *dev, const char *src, const char *dst); +int icc_debugfs_client_init(struct dentry *icc_dir); + +#endif -- cgit v1.3.1