From 10fa1b2cdc899ab471000968af56215bf3c90d8e Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Fri, 22 Apr 2022 17:13:48 +0200 Subject: [PATCH] ACPI: bus: Avoid non-ACPI device objects in walks over children When walking the children of an ACPI device, take extra care to avoid using to_acpi_device() on the ones that are not ACPI devices, because that may lead to out-of-bounds access and memory corruption. While at it, make the function passed to acpi_dev_for_each_child() take a struct acpi_device pointer argument (instead of a struct device one), so it is more straightforward to use. Fixes: b7dd6298db81 ("ACPI: PM: Introduce acpi_dev_power_up_children_with_adr()") Reported-by: kernel test robot BugLink: https://lore.kernel.org/lkml/20220420064725.GB16310@xsang-OptiPlex-9020/ Signed-off-by: Rafael J. Wysocki Reviewed-by: Mika Westerberg --- drivers/acpi/bus.c | 24 ++++++++++++++++++++++-- drivers/acpi/device_pm.c | 5 +---- include/acpi/acpi_bus.h | 2 +- 3 files changed, 24 insertions(+), 7 deletions(-) diff --git a/drivers/acpi/bus.c b/drivers/acpi/bus.c index e807bff..fe0000e 100644 --- a/drivers/acpi/bus.c +++ b/drivers/acpi/bus.c @@ -1070,10 +1070,30 @@ int acpi_bus_for_each_dev(int (*fn)(struct device *, void *), void *data) } EXPORT_SYMBOL_GPL(acpi_bus_for_each_dev); +struct acpi_dev_walk_context { + int (*fn)(struct acpi_device *, void *); + void *data; +}; + +static int acpi_dev_for_one_check(struct device *dev, void *context) +{ + struct acpi_dev_walk_context *adwc = context; + + if (dev->bus != &acpi_bus_type) + return 0; + + return adwc->fn(to_acpi_device(dev), adwc->data); +} + int acpi_dev_for_each_child(struct acpi_device *adev, - int (*fn)(struct device *, void *), void *data) + int (*fn)(struct acpi_device *, void *), void *data) { - return device_for_each_child(&adev->dev, data, fn); + struct acpi_dev_walk_context adwc = { + .fn = fn, + .data = data, + }; + + return device_for_each_child(&adev->dev, &adwc, acpi_dev_for_one_check); } /* -------------------------------------------------------------------------- diff --git a/drivers/acpi/device_pm.c b/drivers/acpi/device_pm.c index 83598b1..37c3d0a 100644 --- a/drivers/acpi/device_pm.c +++ b/drivers/acpi/device_pm.c @@ -425,11 +425,8 @@ bool acpi_bus_power_manageable(acpi_handle handle) } EXPORT_SYMBOL(acpi_bus_power_manageable); -static int acpi_power_up_if_adr_present(struct device *dev, void *not_used) +static int acpi_power_up_if_adr_present(struct acpi_device *adev, void *not_used) { - struct acpi_device *adev; - - adev = to_acpi_device(dev); if (!(adev->flags.power_manageable && adev->pnp.type.bus_address)) return 0; diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h index b44aaff..772590e 100644 --- a/include/acpi/acpi_bus.h +++ b/include/acpi/acpi_bus.h @@ -482,7 +482,7 @@ extern struct bus_type acpi_bus_type; int acpi_bus_for_each_dev(int (*fn)(struct device *, void *), void *data); int acpi_dev_for_each_child(struct acpi_device *adev, - int (*fn)(struct device *, void *), void *data); + int (*fn)(struct acpi_device *, void *), void *data); /* * Events -- 2.7.4