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/pinctrl/pinctrl-utils.h | 35 +++++++++++++++++++++++++++++++++++ 1 file changed, 35 insertions(+) create mode 100644 drivers/pinctrl/pinctrl-utils.h (limited to 'drivers/pinctrl/pinctrl-utils.h') diff --git a/drivers/pinctrl/pinctrl-utils.h b/drivers/pinctrl/pinctrl-utils.h new file mode 100644 index 000000000..203fba257 --- /dev/null +++ b/drivers/pinctrl/pinctrl-utils.h @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Utils functions to implement the pincontrol driver. + * + * Copyright (c) 2013, NVIDIA Corporation. + * + * Author: Laxman Dewangan + */ +#ifndef __PINCTRL_UTILS_H__ +#define __PINCTRL_UTILS_H__ + +#include + +struct pinctrl_dev; +struct pinctrl_map; + +int pinctrl_utils_reserve_map(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, unsigned int reserve); +int pinctrl_utils_add_map_mux(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, const char *group, + const char *function); +int pinctrl_utils_add_map_configs(struct pinctrl_dev *pctldev, + struct pinctrl_map **map, unsigned int *reserved_maps, + unsigned int *num_maps, const char *group, + unsigned long *configs, unsigned int num_configs, + enum pinctrl_map_type type); +int pinctrl_utils_add_config(struct pinctrl_dev *pctldev, + unsigned long **configs, unsigned int *num_configs, + unsigned long config); +void pinctrl_utils_free_map(struct pinctrl_dev *pctldev, + struct pinctrl_map *map, unsigned int num_maps); + +#endif /* __PINCTRL_UTILS_H__ */ -- cgit v1.3.1