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/mfd/intel-lpss.h | 47 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 47 insertions(+) create mode 100644 drivers/mfd/intel-lpss.h (limited to 'drivers/mfd/intel-lpss.h') diff --git a/drivers/mfd/intel-lpss.h b/drivers/mfd/intel-lpss.h new file mode 100644 index 000000000..6f8f668f4 --- /dev/null +++ b/drivers/mfd/intel-lpss.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0-only */ +/* + * Intel LPSS core support. + * + * Copyright (C) 2015, Intel Corporation + * + * Authors: Andy Shevchenko + * Mika Westerberg + */ + +#ifndef __MFD_INTEL_LPSS_H +#define __MFD_INTEL_LPSS_H + +#include +#include + +/* + * Some DSDTs have an unused GEXP ACPI device conflicting with I2C4 resources. + * Set to ignore resource conflicts with ACPI declared SystemMemory regions. + */ +#define QUIRK_IGNORE_RESOURCE_CONFLICTS BIT(0) +/* + * Some devices have misconfigured clock divider due to a firmware bug. + * Set this to force the clock divider to 1:1 ratio. + */ +#define QUIRK_CLOCK_DIVIDER_UNITY BIT(1) + +struct device; +struct resource; +struct software_node; + +struct intel_lpss_platform_info { + struct resource *mem; + int irq; + unsigned int quirks; + unsigned long clk_rate; + const char *clk_con_id; + const struct software_node *swnode; +}; + +int intel_lpss_probe(struct device *dev, + const struct intel_lpss_platform_info *info); +void intel_lpss_remove(struct device *dev); + +extern const struct dev_pm_ops intel_lpss_pm_ops; + +#endif /* __MFD_INTEL_LPSS_H */ -- cgit v1.3.1