From 60d360acddc54344409a710af07c561e025f13f5 Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 20 Jul 2020 15:08:07 -0700 Subject: [PATCH] driver-core: Introduce DEVICE_ATTR_ADMIN_{RO,RW} A common pattern for using plain DEVICE_ATTR() instead of DEVICE_ATTR_RO() and DEVICE_ATTR_RW() is for attributes that want to limit read to only root. I.e. many users of DEVICE_ATTR() are specifying 0400 or 0600 for permissions. Given the expectation that CAP_SYS_ADMIN is needed to access these sensitive attributes add an explicit helper with the _ADMIN_ identifier for DEVICE_ATTR_ADMIN_{RO,RW}. Cc: "Rafael J. Wysocki" Reviewed-by: Greg Kroah-Hartman Signed-off-by: Dan Williams Signed-off-by: Vishal Verma --- include/linux/device.h | 4 ++++ include/linux/sysfs.h | 7 +++++++ 2 files changed, 11 insertions(+) diff --git a/include/linux/device.h b/include/linux/device.h index 15460a5ac024..d7c2570368fa 100644 --- a/include/linux/device.h +++ b/include/linux/device.h @@ -128,8 +128,12 @@ ssize_t device_store_bool(struct device *dev, struct device_attribute *attr, __ATTR_PREALLOC(_name, _mode, _show, _store) #define DEVICE_ATTR_RW(_name) \ struct device_attribute dev_attr_##_name = __ATTR_RW(_name) +#define DEVICE_ATTR_ADMIN_RW(_name) \ + struct device_attribute dev_attr_##_name = __ATTR_RW_MODE(_name, 0600) #define DEVICE_ATTR_RO(_name) \ struct device_attribute dev_attr_##_name = __ATTR_RO(_name) +#define DEVICE_ATTR_ADMIN_RO(_name) \ + struct device_attribute dev_attr_##_name = __ATTR_RO_MODE(_name, 0400) #define DEVICE_ATTR_WO(_name) \ struct device_attribute dev_attr_##_name = __ATTR_WO(_name) #define DEVICE_ULONG_ATTR(_name, _mode, _var) \ diff --git a/include/linux/sysfs.h b/include/linux/sysfs.h index 86067dbe7745..34e84122f635 100644 --- a/include/linux/sysfs.h +++ b/include/linux/sysfs.h @@ -123,6 +123,13 @@ struct attribute_group { .show = _name##_show, \ } +#define __ATTR_RW_MODE(_name, _mode) { \ + .attr = { .name = __stringify(_name), \ + .mode = VERIFY_OCTAL_PERMISSIONS(_mode) }, \ + .show = _name##_show, \ + .store = _name##_store, \ +} + #define __ATTR_WO(_name) { \ .attr = { .name = __stringify(_name), .mode = 0200 }, \ .store = _name##_store, \