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/qcom/cmd-db.h | 48 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 48 insertions(+) create mode 100644 include/soc/qcom/cmd-db.h (limited to 'include/soc/qcom/cmd-db.h') diff --git a/include/soc/qcom/cmd-db.h b/include/soc/qcom/cmd-db.h new file mode 100644 index 000000000..47a6cab75 --- /dev/null +++ b/include/soc/qcom/cmd-db.h @@ -0,0 +1,48 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (c) 2016-2018, The Linux Foundation. All rights reserved. + * Copyright (c) 2024, Qualcomm Innovation Center, Inc. All rights reserved. + */ + +#ifndef __QCOM_COMMAND_DB_H__ +#define __QCOM_COMMAND_DB_H__ + +#include + +enum cmd_db_hw_type { + CMD_DB_HW_INVALID = 0, + CMD_DB_HW_MIN = 3, + CMD_DB_HW_ARC = CMD_DB_HW_MIN, + CMD_DB_HW_VRM = 4, + CMD_DB_HW_BCM = 5, + CMD_DB_HW_MAX = CMD_DB_HW_BCM, + CMD_DB_HW_ALL = 0xff, +}; + +#if IS_ENABLED(CONFIG_QCOM_COMMAND_DB) +u32 cmd_db_read_addr(const char *resource_id); + +const void *cmd_db_read_aux_data(const char *resource_id, size_t *len); + +bool cmd_db_match_resource_addr(u32 addr1, u32 addr2); + +enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id); + +int cmd_db_ready(void); +#else +static inline u32 cmd_db_read_addr(const char *resource_id) +{ return 0; } + +static inline const void *cmd_db_read_aux_data(const char *resource_id, size_t *len) +{ return ERR_PTR(-ENODEV); } + +static inline bool cmd_db_match_resource_addr(u32 addr1, u32 addr2) +{ return false; } + +static inline enum cmd_db_hw_type cmd_db_read_slave_id(const char *resource_id) +{ return -ENODEV; } + +static inline int cmd_db_ready(void) +{ return -ENODEV; } +#endif /* CONFIG_QCOM_COMMAND_DB */ +#endif /* __QCOM_COMMAND_DB_H__ */ -- cgit v1.3.1