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/clk/clk.h | 38 ++++++++++++++++++++++++++++++++++++++ 1 file changed, 38 insertions(+) create mode 100644 drivers/clk/clk.h (limited to 'drivers/clk/clk.h') diff --git a/drivers/clk/clk.h b/drivers/clk/clk.h new file mode 100644 index 000000000..2d801900c --- /dev/null +++ b/drivers/clk/clk.h @@ -0,0 +1,38 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * Copyright (C) 2013 Samsung Electronics Co., Ltd. + * Sylwester Nawrocki + */ + +struct clk_hw; +struct device; +struct of_phandle_args; + +#if defined(CONFIG_OF) && defined(CONFIG_COMMON_CLK) +struct clk_hw *of_clk_get_hw(struct device_node *np, + int index, const char *con_id); +#else /* !CONFIG_COMMON_CLK || !CONFIG_OF */ +static inline struct clk_hw *of_clk_get_hw(struct device_node *np, + int index, const char *con_id) +{ + return ERR_PTR(-ENOENT); +} +#endif + +struct clk_hw *clk_find_hw(const char *dev_id, const char *con_id); + +#ifdef CONFIG_COMMON_CLK +struct clk *clk_hw_create_clk(struct device *dev, struct clk_hw *hw, + const char *dev_id, const char *con_id); +void __clk_put(struct clk *clk); +#else +/* All these casts to avoid ifdefs in clkdev... */ +static inline struct clk * +clk_hw_create_clk(struct device *dev, struct clk_hw *hw, const char *dev_id, + const char *con_id) +{ + return (struct clk *)hw; +} +static inline void __clk_put(struct clk *clk) { } + +#endif -- cgit v1.3.1