commit 416de0246f35f43d871a57939671fe814f4455ee upstream.
When booting a kernel with CONFIG_CFI_CLANG, there is a CFI failure when accessing any of the values under /sys/devices/system/cpu/intel_uncore_frequency/package_00_die_00:
$ cat /sys/devices/system/cpu/intel_uncore_frequency/package_00_die_00/max_freq_khz fish: Job 1, 'cat /sys/devices/system/cpu/int…' terminated by signal SIGSEGV (Address boundary error)
$ sudo dmesg &| grep 'CFI failure' [ 170.953925] CFI failure at kobj_attr_show+0x19/0x30 (target: show_max_freq_khz+0x0/0xc0 [intel_uncore_frequency_common]; expected type: 0xd34078c5
The sysfs callback functions such as show_domain_id() are written as if they are going to be called by dev_attr_show() but as the above message shows, they are instead called by kobj_attr_show(). kCFI checks that the destination of an indirect jump has the exact same type as the prototype of the function pointer it is called through and fails when they do not.
These callbacks are called through kobj_attr_show() because uncore_root_kobj was initialized with kobject_create_and_add(), which means uncore_root_kobj has a ->sysfs_ops of kobj_sysfs_ops from kobject_create(), which uses kobj_attr_show() as its ->show() value.
The only reason there has not been a more noticeable problem until this point is that 'struct kobj_attribute' and 'struct device_attribute' have the same layout, so getting the callback from container_of() works the same with either value.
Change all the callbacks and their uses to be compatible with kobj_attr_show() and kobj_attr_store(), which resolves the kCFI failure and allows the sysfs files to work properly.
Closes: https://github.com/ClangBuiltLinux/linux/issues/1974 Fixes: ae7b2ce57851 ("platform/x86/intel/uncore-freq: Use sysfs API to create attributes") Cc: stable@vger.kernel.org Signed-off-by: Nathan Chancellor nathan@kernel.org Reviewed-by: Sami Tolvanen samitolvanen@google.com Acked-by: Srinivas Pandruvada srinivas.pandruvada@linux.intel.com Link: https://lore.kernel.org/r/20240104-intel-uncore-freq-kcfi-fix-v1-1-bf1e8939a... Signed-off-by: Hans de Goede hdegoede@redhat.com [nathan: Fix conflicts due to lack of 9b8dea80e3cb in 6.1] Signed-off-by: Nathan Chancellor nathan@kernel.org --- .../uncore-frequency-common.c | 64 +++++++++---------- .../uncore-frequency-common.h | 20 +++--- 2 files changed, 42 insertions(+), 42 deletions(-)
diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c index 9b12fe8e95c9..dd2e654daf4b 100644 --- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.c @@ -74,30 +74,30 @@ static ssize_t show_perf_status_freq_khz(struct uncore_data *data, char *buf) }
#define store_uncore_min_max(name, min_max) \ - static ssize_t store_##name(struct device *dev, \ - struct device_attribute *attr, \ + static ssize_t store_##name(struct kobject *kobj, \ + struct kobj_attribute *attr, \ const char *buf, size_t count) \ { \ - struct uncore_data *data = container_of(attr, struct uncore_data, name##_dev_attr);\ + struct uncore_data *data = container_of(attr, struct uncore_data, name##_kobj_attr);\ \ return store_min_max_freq_khz(data, buf, count, \ min_max); \ }
#define show_uncore_min_max(name, min_max) \ - static ssize_t show_##name(struct device *dev, \ - struct device_attribute *attr, char *buf)\ + static ssize_t show_##name(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf)\ { \ - struct uncore_data *data = container_of(attr, struct uncore_data, name##_dev_attr);\ + struct uncore_data *data = container_of(attr, struct uncore_data, name##_kobj_attr);\ \ return show_min_max_freq_khz(data, buf, min_max); \ }
#define show_uncore_perf_status(name) \ - static ssize_t show_##name(struct device *dev, \ - struct device_attribute *attr, char *buf)\ + static ssize_t show_##name(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf)\ { \ - struct uncore_data *data = container_of(attr, struct uncore_data, name##_dev_attr);\ + struct uncore_data *data = container_of(attr, struct uncore_data, name##_kobj_attr);\ \ return show_perf_status_freq_khz(data, buf); \ } @@ -111,11 +111,11 @@ show_uncore_min_max(max_freq_khz, 1); show_uncore_perf_status(current_freq_khz);
#define show_uncore_data(member_name) \ - static ssize_t show_##member_name(struct device *dev, \ - struct device_attribute *attr, char *buf)\ + static ssize_t show_##member_name(struct kobject *kobj, \ + struct kobj_attribute *attr, char *buf)\ { \ struct uncore_data *data = container_of(attr, struct uncore_data,\ - member_name##_dev_attr);\ + member_name##_kobj_attr);\ \ return sysfs_emit(buf, "%u\n", \ data->member_name); \ @@ -126,29 +126,29 @@ show_uncore_data(initial_max_freq_khz);
#define init_attribute_rw(_name) \ do { \ - sysfs_attr_init(&data->_name##_dev_attr.attr); \ - data->_name##_dev_attr.show = show_##_name; \ - data->_name##_dev_attr.store = store_##_name; \ - data->_name##_dev_attr.attr.name = #_name; \ - data->_name##_dev_attr.attr.mode = 0644; \ + sysfs_attr_init(&data->_name##_kobj_attr.attr); \ + data->_name##_kobj_attr.show = show_##_name; \ + data->_name##_kobj_attr.store = store_##_name; \ + data->_name##_kobj_attr.attr.name = #_name; \ + data->_name##_kobj_attr.attr.mode = 0644; \ } while (0)
#define init_attribute_ro(_name) \ do { \ - sysfs_attr_init(&data->_name##_dev_attr.attr); \ - data->_name##_dev_attr.show = show_##_name; \ - data->_name##_dev_attr.store = NULL; \ - data->_name##_dev_attr.attr.name = #_name; \ - data->_name##_dev_attr.attr.mode = 0444; \ + sysfs_attr_init(&data->_name##_kobj_attr.attr); \ + data->_name##_kobj_attr.show = show_##_name; \ + data->_name##_kobj_attr.store = NULL; \ + data->_name##_kobj_attr.attr.name = #_name; \ + data->_name##_kobj_attr.attr.mode = 0444; \ } while (0)
#define init_attribute_root_ro(_name) \ do { \ - sysfs_attr_init(&data->_name##_dev_attr.attr); \ - data->_name##_dev_attr.show = show_##_name; \ - data->_name##_dev_attr.store = NULL; \ - data->_name##_dev_attr.attr.name = #_name; \ - data->_name##_dev_attr.attr.mode = 0400; \ + sysfs_attr_init(&data->_name##_kobj_attr.attr); \ + data->_name##_kobj_attr.show = show_##_name; \ + data->_name##_kobj_attr.store = NULL; \ + data->_name##_kobj_attr.attr.name = #_name; \ + data->_name##_kobj_attr.attr.mode = 0400; \ } while (0)
static int create_attr_group(struct uncore_data *data, char *name) @@ -161,14 +161,14 @@ static int create_attr_group(struct uncore_data *data, char *name) init_attribute_ro(initial_max_freq_khz); init_attribute_root_ro(current_freq_khz);
- data->uncore_attrs[index++] = &data->max_freq_khz_dev_attr.attr; - data->uncore_attrs[index++] = &data->min_freq_khz_dev_attr.attr; - data->uncore_attrs[index++] = &data->initial_min_freq_khz_dev_attr.attr; - data->uncore_attrs[index++] = &data->initial_max_freq_khz_dev_attr.attr; + data->uncore_attrs[index++] = &data->max_freq_khz_kobj_attr.attr; + data->uncore_attrs[index++] = &data->min_freq_khz_kobj_attr.attr; + data->uncore_attrs[index++] = &data->initial_min_freq_khz_kobj_attr.attr; + data->uncore_attrs[index++] = &data->initial_max_freq_khz_kobj_attr.attr;
ret = uncore_read_freq(data, &freq); if (!ret) - data->uncore_attrs[index++] = &data->current_freq_khz_dev_attr.attr; + data->uncore_attrs[index++] = &data->current_freq_khz_kobj_attr.attr;
data->uncore_attrs[index] = NULL;
diff --git a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.h b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.h index f5dcfa2fb285..2d9dc3151d6e 100644 --- a/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.h +++ b/drivers/platform/x86/intel/uncore-frequency/uncore-frequency-common.h @@ -23,11 +23,11 @@ * @die_id: Die id for this instance * @name: Sysfs entry name for this instance * @uncore_attr_group: Attribute group storage - * @max_freq_khz_dev_attr: Storage for device attribute max_freq_khz - * @mix_freq_khz_dev_attr: Storage for device attribute min_freq_khz - * @initial_max_freq_khz_dev_attr: Storage for device attribute initial_max_freq_khz - * @initial_min_freq_khz_dev_attr: Storage for device attribute initial_min_freq_khz - * @current_freq_khz_dev_attr: Storage for device attribute current_freq_khz + * @max_freq_khz_dev_attr: Storage for kobject attribute max_freq_khz + * @mix_freq_khz_dev_attr: Storage for kobject attribute min_freq_khz + * @initial_max_freq_khz_dev_attr: Storage for kobject attribute initial_max_freq_khz + * @initial_min_freq_khz_dev_attr: Storage for kobject attribute initial_min_freq_khz + * @current_freq_khz_dev_attr: Storage for kobject attribute current_freq_khz * @uncore_attrs: Attribute storage for group creation * * This structure is used to encapsulate all data related to uncore sysfs @@ -44,11 +44,11 @@ struct uncore_data { char name[32];
struct attribute_group uncore_attr_group; - struct device_attribute max_freq_khz_dev_attr; - struct device_attribute min_freq_khz_dev_attr; - struct device_attribute initial_max_freq_khz_dev_attr; - struct device_attribute initial_min_freq_khz_dev_attr; - struct device_attribute current_freq_khz_dev_attr; + struct kobj_attribute max_freq_khz_kobj_attr; + struct kobj_attribute min_freq_khz_kobj_attr; + struct kobj_attribute initial_max_freq_khz_kobj_attr; + struct kobj_attribute initial_min_freq_khz_kobj_attr; + struct kobj_attribute current_freq_khz_kobj_attr; struct attribute *uncore_attrs[6]; };
base-commit: 883d1a9562083922c6d293e9adad8cca4626adf3