From eb617dd25ca176f3fee24f873f0fd60010773d67 Mon Sep 17 00:00:00 2001 From: Kurt Borja Date: Mon, 30 Jun 2025 00:43:12 -0300 Subject: platform/x86: dell-wmi-sysman: Fix WMI data block retrieval in sysfs callbacks MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit After retrieving WMI data blocks in sysfs callbacks, check for the validity of them before dereferencing their content. Reported-by: Jan Graczyk Closes: https://lore.kernel.org/r/CAHk-=wgMiSKXf7SvQrfEnxVtmT=QVQPjJdNjfm3aXS7wc=rzTw@mail.gmail.com/ Fixes: e8a60aa7404b ("platform/x86: Introduce support for Systems Management Driver over WMI for Dell Systems") Suggested-by: Linus Torvalds Reviewed-by: Armin Wolf Signed-off-by: Kurt Borja Link: https://lore.kernel.org/r/20250630-sysman-fix-v2-1-d185674d0a30@gmail.com Reviewed-by: Ilpo Järvinen Signed-off-by: Ilpo Järvinen --- drivers/platform/x86/dell/dell-wmi-sysman/dell-wmi-sysman.h | 5 +++++ drivers/platform/x86/dell/dell-wmi-sysman/enum-attributes.c | 5 +++-- drivers/platform/x86/dell/dell-wmi-sysman/int-attributes.c | 5 +++-- drivers/platform/x86/dell/dell-wmi-sysman/passobj-attributes.c | 5 +++-- drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c | 5 +++-- drivers/platform/x86/dell/dell-wmi-sysman/sysman.c | 8 ++++---- 6 files changed, 21 insertions(+), 12 deletions(-) diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/dell-wmi-sysman.h b/drivers/platform/x86/dell/dell-wmi-sysman/dell-wmi-sysman.h index 3ad33a094588..817ee7ba07ca 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/dell-wmi-sysman.h +++ b/drivers/platform/x86/dell/dell-wmi-sysman/dell-wmi-sysman.h @@ -89,6 +89,11 @@ extern struct wmi_sysman_priv wmi_priv; enum { ENUM, INT, STR, PO }; +#define ENUM_MIN_ELEMENTS 8 +#define INT_MIN_ELEMENTS 9 +#define STR_MIN_ELEMENTS 8 +#define PO_MIN_ELEMENTS 4 + enum { ATTR_NAME, DISPL_NAME_LANG_CODE, diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/enum-attributes.c b/drivers/platform/x86/dell/dell-wmi-sysman/enum-attributes.c index 8cc212c85266..fc2f58b4cbc6 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/enum-attributes.c +++ b/drivers/platform/x86/dell/dell-wmi-sysman/enum-attributes.c @@ -23,9 +23,10 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_ENUMERATION_ATTRIBUTE_GUID); if (!obj) return -EIO; - if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) { + if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < ENUM_MIN_ELEMENTS || + obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) { kfree(obj); - return -EINVAL; + return -EIO; } ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer); kfree(obj); diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/int-attributes.c b/drivers/platform/x86/dell/dell-wmi-sysman/int-attributes.c index 951e75b538fa..735248064239 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/int-attributes.c +++ b/drivers/platform/x86/dell/dell-wmi-sysman/int-attributes.c @@ -25,9 +25,10 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_INTEGER_ATTRIBUTE_GUID); if (!obj) return -EIO; - if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_INTEGER) { + if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < INT_MIN_ELEMENTS || + obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_INTEGER) { kfree(obj); - return -EINVAL; + return -EIO; } ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[CURRENT_VAL].integer.value); kfree(obj); diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/passobj-attributes.c b/drivers/platform/x86/dell/dell-wmi-sysman/passobj-attributes.c index d8f1bf5e58a0..3167e06d416e 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/passobj-attributes.c +++ b/drivers/platform/x86/dell/dell-wmi-sysman/passobj-attributes.c @@ -26,9 +26,10 @@ static ssize_t is_enabled_show(struct kobject *kobj, struct kobj_attribute *attr obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_PASSOBJ_ATTRIBUTE_GUID); if (!obj) return -EIO; - if (obj->package.elements[IS_PASS_SET].type != ACPI_TYPE_INTEGER) { + if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < PO_MIN_ELEMENTS || + obj->package.elements[IS_PASS_SET].type != ACPI_TYPE_INTEGER) { kfree(obj); - return -EINVAL; + return -EIO; } ret = snprintf(buf, PAGE_SIZE, "%lld\n", obj->package.elements[IS_PASS_SET].integer.value); kfree(obj); diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c b/drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c index c392f0ecf8b5..0d2c74f8d1aa 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c +++ b/drivers/platform/x86/dell/dell-wmi-sysman/string-attributes.c @@ -25,9 +25,10 @@ static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *a obj = get_wmiobj_pointer(instance_id, DELL_WMI_BIOS_STRING_ATTRIBUTE_GUID); if (!obj) return -EIO; - if (obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) { + if (obj->type != ACPI_TYPE_PACKAGE || obj->package.count < STR_MIN_ELEMENTS || + obj->package.elements[CURRENT_VAL].type != ACPI_TYPE_STRING) { kfree(obj); - return -EINVAL; + return -EIO; } ret = snprintf(buf, PAGE_SIZE, "%s\n", obj->package.elements[CURRENT_VAL].string.pointer); kfree(obj); diff --git a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c index d00389b860e4..3c74d5e8350a 100644 --- a/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c +++ b/drivers/platform/x86/dell/dell-wmi-sysman/sysman.c @@ -407,10 +407,10 @@ static int init_bios_attributes(int attr_type, const char *guid) return retval; switch (attr_type) { - case ENUM: min_elements = 8; break; - case INT: min_elements = 9; break; - case STR: min_elements = 8; break; - case PO: min_elements = 4; break; + case ENUM: min_elements = ENUM_MIN_ELEMENTS; break; + case INT: min_elements = INT_MIN_ELEMENTS; break; + case STR: min_elements = STR_MIN_ELEMENTS; break; + case PO: min_elements = PO_MIN_ELEMENTS; break; default: pr_err("Error: Unknown attr_type: %d\n", attr_type); return -EINVAL; -- cgit v1.2.3