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/pmdomain/st/Kconfig | 5 ++ drivers/pmdomain/st/Makefile | 2 + drivers/pmdomain/st/ste-ux500-pm-domain.c | 94 +++++++++++++++++++++++++++++++ 3 files changed, 101 insertions(+) create mode 100644 drivers/pmdomain/st/Kconfig create mode 100644 drivers/pmdomain/st/Makefile create mode 100644 drivers/pmdomain/st/ste-ux500-pm-domain.c (limited to 'drivers/pmdomain/st') diff --git a/drivers/pmdomain/st/Kconfig b/drivers/pmdomain/st/Kconfig new file mode 100644 index 000000000..a77a70211 --- /dev/null +++ b/drivers/pmdomain/st/Kconfig @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0-only +config UX500_PM_DOMAIN + bool "ST-Ericsson ux500 Power Domain" + depends on ARCH_U8500 || COMPILE_TEST + default ARCH_U8500 diff --git a/drivers/pmdomain/st/Makefile b/drivers/pmdomain/st/Makefile new file mode 100644 index 000000000..6d8b617eb --- /dev/null +++ b/drivers/pmdomain/st/Makefile @@ -0,0 +1,2 @@ +# SPDX-License-Identifier: GPL-2.0-only +obj-$(CONFIG_UX500_PM_DOMAIN) += ste-ux500-pm-domain.o diff --git a/drivers/pmdomain/st/ste-ux500-pm-domain.c b/drivers/pmdomain/st/ste-ux500-pm-domain.c new file mode 100644 index 000000000..6896cb4a7 --- /dev/null +++ b/drivers/pmdomain/st/ste-ux500-pm-domain.c @@ -0,0 +1,94 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Copyright (C) 2014 Linaro Ltd. + * + * Author: Ulf Hansson + * + * Implements PM domains using the generic PM domain for ux500. + */ +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +static int pd_power_off(struct generic_pm_domain *domain) +{ + /* + * Handle the gating of the PM domain regulator here. + * + * Drivers/subsystems handling devices in the PM domain needs to perform + * register context save/restore from their respective runtime PM + * callbacks, to be able to enable PM domain gating/ungating. + */ + return 0; +} + +static int pd_power_on(struct generic_pm_domain *domain) +{ + /* + * Handle the ungating of the PM domain regulator here. + * + * Drivers/subsystems handling devices in the PM domain needs to perform + * register context save/restore from their respective runtime PM + * callbacks, to be able to enable PM domain gating/ungating. + */ + return 0; +} + +static struct generic_pm_domain ux500_pm_domain_vape = { + .name = "VAPE", + .power_off = pd_power_off, + .power_on = pd_power_on, +}; + +static struct generic_pm_domain *ux500_pm_domains[NR_DOMAINS] = { + [DOMAIN_VAPE] = &ux500_pm_domain_vape, +}; + +static const struct of_device_id ux500_pm_domain_matches[] = { + { .compatible = "stericsson,ux500-pm-domains", }, + { }, +}; + +static int ux500_pm_domains_probe(struct platform_device *pdev) +{ + struct device_node *np = pdev->dev.of_node; + struct genpd_onecell_data *genpd_data; + int i; + + if (!np) + return -ENODEV; + + genpd_data = kzalloc_obj(*genpd_data); + if (!genpd_data) + return -ENOMEM; + + genpd_data->domains = ux500_pm_domains; + genpd_data->num_domains = ARRAY_SIZE(ux500_pm_domains); + + for (i = 0; i < ARRAY_SIZE(ux500_pm_domains); ++i) + pm_genpd_init(ux500_pm_domains[i], NULL, false); + + of_genpd_add_provider_onecell(np, genpd_data); + return 0; +} + +static struct platform_driver ux500_pm_domains_driver = { + .probe = ux500_pm_domains_probe, + .driver = { + .name = "ux500_pm_domains", + .of_match_table = ux500_pm_domain_matches, + }, +}; + +static int __init ux500_pm_domains_init(void) +{ + return platform_driver_register(&ux500_pm_domains_driver); +} +arch_initcall(ux500_pm_domains_init); -- cgit v1.3.1