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/soc/microchip/mpfs.h | 54 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 54 insertions(+) create mode 100644 include/soc/microchip/mpfs.h (limited to 'include/soc/microchip') diff --git a/include/soc/microchip/mpfs.h b/include/soc/microchip/mpfs.h new file mode 100644 index 000000000..ec04c98a8 --- /dev/null +++ b/include/soc/microchip/mpfs.h @@ -0,0 +1,54 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * + * Microchip PolarFire SoC (MPFS) + * + * Copyright (c) 2020 Microchip Corporation. All rights reserved. + * + * Author: Conor Dooley + * + */ + +#ifndef __SOC_MPFS_H__ +#define __SOC_MPFS_H__ + +#include +#include +#include + +struct mpfs_sys_controller; + +struct mpfs_mss_msg { + u8 cmd_opcode; + u16 cmd_data_size; + struct mpfs_mss_response *response; + u8 *cmd_data; + u16 mbox_offset; + u16 resp_offset; +}; + +struct mpfs_mss_response { + u32 resp_status; + u32 *resp_msg; + u16 resp_size; +}; + +#if IS_ENABLED(CONFIG_POLARFIRE_SOC_SYS_CTRL) + +int mpfs_blocking_transaction(struct mpfs_sys_controller *mpfs_client, struct mpfs_mss_msg *msg); + +struct mpfs_sys_controller *mpfs_sys_controller_get(struct device *dev); + +struct mtd_info *mpfs_sys_controller_get_flash(struct mpfs_sys_controller *mpfs_client); + +#endif /* if IS_ENABLED(CONFIG_POLARFIRE_SOC_SYS_CTRL) */ + +#if IS_ENABLED(CONFIG_MCHP_CLK_MPFS) +#if IS_ENABLED(CONFIG_RESET_POLARFIRE_SOC) +int mpfs_reset_controller_register(struct device *clk_dev, struct regmap *map); +#else +static inline int mpfs_reset_controller_register(struct device *clk_dev, void __iomem *base) { return 0; } +#endif /* if IS_ENABLED(CONFIG_RESET_POLARFIRE_SOC) */ +#endif /* if IS_ENABLED(CONFIG_MCHP_CLK_MPFS) */ + +#endif /* __SOC_MPFS_H__ */ -- cgit v1.3.1