drivers core: Use sysfs_emit and sysfs_emit_at for show(device *...) functions

mainline inclusion
from mainline-v5.10-rc1
commit aa838896
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I5C32F
CVE: CVE-2022-20166

----------------------------------------------

Convert the various sprintf fmaily calls in sysfs device show functions
to sysfs_emit and sysfs_emit_at for PAGE_SIZE buffer safety.

Done with:

$ spatch -sp-file sysfs_emit_dev.cocci --in-place --max-width=80 .

And cocci script:

$ cat sysfs_emit_dev.cocci
@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	sprintf(buf,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	snprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	scnprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	return
-	strcpy(buf, chr);
+	sysfs_emit(buf, chr);
	...>
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	sprintf(buf,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	snprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
	len =
-	scnprintf(buf, PAGE_SIZE,
+	sysfs_emit(buf,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
identifier len;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	<...
-	len += scnprintf(buf + len, PAGE_SIZE - len,
+	len += sysfs_emit_at(buf, len,
	...);
	...>
	return len;
}

@@
identifier d_show;
identifier dev, attr, buf;
expression chr;
@@

ssize_t d_show(struct device *dev, struct device_attribute *attr, char *buf)
{
	...
-	strcpy(buf, chr);
-	return strlen(buf);
+	return sysfs_emit(buf, chr);
}
Signed-off-by: NJoe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/3d033c33056d88bbe34d4ddb62afd05ee166ab9a.1600285923.git.joe@perches.comSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Conflicts:
	drivers/base/node.c
Signed-off-by: NGuo Mengqi <guomengqi3@huawei.com>
Reviewed-by: NWeilong Chen <chenweilong@huawei.com>
Reviewed-by: NXiu Jianfeng <xiujianfeng@huawei.com>
Signed-off-by: NYongqiang Liu <liuyongqiang13@huawei.com>

drivers/base/arch_topology.c

@@ -42,7 +42,8 @@ static ssize_t cpu_capacity_show(struct device *dev,
 {
 	struct cpu *cpu = container_of(dev, struct cpu, dev);
 
-	return sprintf(buf, "%lu\n", topology_get_cpu_scale(NULL, cpu->dev.id));
+	return sysfs_emit(buf, "%lu\n",
+			  topology_get_cpu_scale(NULL, cpu->dev.id));
 }
 
 static DEVICE_ATTR_RO(cpu_capacity);

drivers/base/cacheinfo.c

@@ -415,7 +415,7 @@ static ssize_t size_show(struct device *dev,
 {
 	struct cacheinfo *this_leaf = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%uK\n", this_leaf->size >> 10);
+	return sysfs_emit(buf, "%uK\n", this_leaf->size >> 10);
 }
 
 static ssize_t shared_cpumap_show_func(struct device *dev, bool list, char *buf)
@@ -445,11 +445,11 @@ static ssize_t type_show(struct device *dev,
 
 	switch (this_leaf->type) {
 	case CACHE_TYPE_DATA:
-		return sprintf(buf, "Data\n");
+		return sysfs_emit(buf, "Data\n");
 	case CACHE_TYPE_INST:
-		return sprintf(buf, "Instruction\n");
+		return sysfs_emit(buf, "Instruction\n");
 	case CACHE_TYPE_UNIFIED:
-		return sprintf(buf, "Unified\n");
+		return sysfs_emit(buf, "Unified\n");
 	default:
 		return -EINVAL;
 	}
@@ -463,11 +463,11 @@ static ssize_t allocation_policy_show(struct device *dev,
 	int n = 0;
 
 	if ((ci_attr & CACHE_READ_ALLOCATE) && (ci_attr & CACHE_WRITE_ALLOCATE))
-		n = sprintf(buf, "ReadWriteAllocate\n");
+		n = sysfs_emit(buf, "ReadWriteAllocate\n");
 	else if (ci_attr & CACHE_READ_ALLOCATE)
-		n = sprintf(buf, "ReadAllocate\n");
+		n = sysfs_emit(buf, "ReadAllocate\n");
 	else if (ci_attr & CACHE_WRITE_ALLOCATE)
-		n = sprintf(buf, "WriteAllocate\n");
+		n = sysfs_emit(buf, "WriteAllocate\n");
 	return n;
 }
 
@@ -479,9 +479,9 @@ static ssize_t write_policy_show(struct device *dev,
 	int n = 0;
 
 	if (ci_attr & CACHE_WRITE_THROUGH)
-		n = sprintf(buf, "WriteThrough\n");
+		n = sysfs_emit(buf, "WriteThrough\n");
 	else if (ci_attr & CACHE_WRITE_BACK)
-		n = sprintf(buf, "WriteBack\n");
+		n = sysfs_emit(buf, "WriteBack\n");
 	return n;
 }
 

drivers/base/core.c

@@ -994,7 +994,7 @@ ssize_t device_show_ulong(struct device *dev,
 			  char *buf)
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
-	return snprintf(buf, PAGE_SIZE, "%lx\n", *(unsigned long *)(ea->var));
+	return sysfs_emit(buf, "%lx\n", *(unsigned long *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_ulong);
 
@@ -1019,7 +1019,7 @@ ssize_t device_show_int(struct device *dev,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(int *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(int *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_int);
 
@@ -1040,7 +1040,7 @@ ssize_t device_show_bool(struct device *dev, struct device_attribute *attr,
 {
 	struct dev_ext_attribute *ea = to_ext_attr(attr);
 
-	return snprintf(buf, PAGE_SIZE, "%d\n", *(bool *)(ea->var));
+	return sysfs_emit(buf, "%d\n", *(bool *)(ea->var));
 }
 EXPORT_SYMBOL_GPL(device_show_bool);
 
@@ -1273,7 +1273,7 @@ static ssize_t online_show(struct device *dev, struct device_attribute *attr,
 	device_lock(dev);
 	val = !dev->offline;
 	device_unlock(dev);
-	return sprintf(buf, "%u\n", val);
+	return sysfs_emit(buf, "%u\n", val);
 }
 
 static ssize_t online_store(struct device *dev, struct device_attribute *attr,

drivers/base/cpu.c

@@ -156,7 +156,7 @@ static ssize_t show_crash_notes(struct device *dev, struct device_attribute *att
 	 * operation should be safe. No locking required.
 	 */
 	addr = per_cpu_ptr_to_phys(per_cpu_ptr(crash_notes, cpunum));
-	rc = sprintf(buf, "%Lx\n", addr);
+	rc = sysfs_emit(buf, "%Lx\n", addr);
 	return rc;
 }
 static DEVICE_ATTR(crash_notes, 0400, show_crash_notes, NULL);
@@ -167,7 +167,7 @@ static ssize_t show_crash_notes_size(struct device *dev,
 {
 	ssize_t rc;
 
-	rc = sprintf(buf, "%zu\n", sizeof(note_buf_t));
+	rc = sysfs_emit(buf, "%zu\n", sizeof(note_buf_t));
 	return rc;
 }
 static DEVICE_ATTR(crash_notes_size, 0400, show_crash_notes_size, NULL);
@@ -328,8 +328,8 @@ static ssize_t print_cpu_modalias(struct device *dev,
 	ssize_t n;
 	u32 i;
 
-	n = sprintf(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
-		    CPU_FEATURE_TYPEVAL);
+	n = sysfs_emit(buf, "cpu:type:" CPU_FEATURE_TYPEFMT ":feature:",
+		       CPU_FEATURE_TYPEVAL);
 
 	for (i = 0; i < MAX_CPU_FEATURES; i++)
 		if (cpu_have_feature(i)) {
@@ -519,56 +519,56 @@ static void __init cpu_dev_register_generic(void)
 ssize_t __weak cpu_show_meltdown(struct device *dev,
 				 struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v1(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spectre_v2(struct device *dev,
 				   struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_spec_store_bypass(struct device *dev,
 					  struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_l1tf(struct device *dev,
 			     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_mds(struct device *dev,
 			    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_tsx_async_abort(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_itlb_multihit(struct device *dev,
 			    struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 ssize_t __weak cpu_show_srbds(struct device *dev,
 			      struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "Not affected\n");
+	return sysfs_emit(buf, "Not affected\n");
 }
 
 static DEVICE_ATTR(meltdown, 0444, cpu_show_meltdown, NULL);

drivers/base/firmware_loader/fallback.c

@@ -216,7 +216,7 @@ static ssize_t firmware_loading_show(struct device *dev,
 		loading = fw_sysfs_loading(fw_sysfs->fw_priv);
 	mutex_unlock(&fw_lock);
 
-	return sprintf(buf, "%d\n", loading);
+	return sysfs_emit(buf, "%d\n", loading);
 }
 
 /* one pages buffer should be mapped/unmapped only once */

drivers/base/memory.c

@@ -140,7 +140,7 @@ static ssize_t phys_index_show(struct device *dev,
 	unsigned long phys_index;
 
 	phys_index = mem->start_section_nr / sections_per_block;
-	return sprintf(buf, "%08lx\n", phys_index);
+	return sysfs_emit(buf, "%08lx\n", phys_index);
 }
 
 /*
@@ -164,7 +164,7 @@ static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
 	}
 
 out:
-	return sprintf(buf, "%d\n", ret);
+	return sysfs_emit(buf, "%d\n", ret);
 }
 
 /*
@@ -182,17 +182,17 @@ static ssize_t state_show(struct device *dev, struct device_attribute *attr,
 	 */
 	switch (mem->state) {
 	case MEM_ONLINE:
-		len = sprintf(buf, "online\n");
+		len = sysfs_emit(buf, "online\n");
 		break;
 	case MEM_OFFLINE:
-		len = sprintf(buf, "offline\n");
+		len = sysfs_emit(buf, "offline\n");
 		break;
 	case MEM_GOING_OFFLINE:
-		len = sprintf(buf, "going-offline\n");
+		len = sysfs_emit(buf, "going-offline\n");
 		break;
 	default:
-		len = sprintf(buf, "ERROR-UNKNOWN-%ld\n",
-				mem->state);
+		len = sysfs_emit(buf, "ERROR-UNKNOWN-%ld\n",
+				 mem->state);
 		WARN_ON(1);
 		break;
 	}
@@ -389,7 +389,7 @@ static ssize_t phys_device_show(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
 	struct memory_block *mem = to_memory_block(dev);
-	return sprintf(buf, "%d\n", mem->phys_device);
+	return sysfs_emit(buf, "%d\n", mem->phys_device);
 }
 
 #ifdef CONFIG_MEMORY_HOTREMOVE
@@ -427,7 +427,7 @@ static ssize_t valid_zones_show(struct device *dev,
 		 */
 		if (!test_pages_in_a_zone(start_pfn, start_pfn + nr_pages,
 					  &valid_start_pfn, &valid_end_pfn))
-			return sprintf(buf, "none\n");
+			return sysfs_emit(buf, "none\n");
 		start_pfn = valid_start_pfn;
 		strcat(buf, page_zone(pfn_to_page(start_pfn))->name);
 		goto out;
@@ -461,7 +461,7 @@ static DEVICE_ATTR_RO(removable);
 static ssize_t block_size_bytes_show(struct device *dev,
 				     struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%lx\n", get_memory_block_size());
+	return sysfs_emit(buf, "%lx\n", get_memory_block_size());
 }
 
 static DEVICE_ATTR_RO(block_size_bytes);
@@ -473,8 +473,8 @@ static DEVICE_ATTR_RO(block_size_bytes);
 static ssize_t auto_online_blocks_show(struct device *dev,
 				       struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%s\n",
-		       online_type_to_str[memhp_default_online_type]);
+	return sysfs_emit(buf, "%s\n",
+			  online_type_to_str[memhp_default_online_type]);
 }
 
 static ssize_t auto_online_blocks_store(struct device *dev,

drivers/base/node.c

@@ -457,19 +457,19 @@ static DEVICE_ATTR(meminfo, S_IRUGO, node_read_meminfo, NULL);
 static ssize_t node_read_numastat(struct device *dev,
 				struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf,
-		       "numa_hit %lu\n"
-		       "numa_miss %lu\n"
-		       "numa_foreign %lu\n"
-		       "interleave_hit %lu\n"
-		       "local_node %lu\n"
-		       "other_node %lu\n",
-		       sum_zone_numa_state(dev->id, NUMA_HIT),
-		       sum_zone_numa_state(dev->id, NUMA_MISS),
-		       sum_zone_numa_state(dev->id, NUMA_FOREIGN),
-		       sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
-		       sum_zone_numa_state(dev->id, NUMA_LOCAL),
-		       sum_zone_numa_state(dev->id, NUMA_OTHER));
+	return sysfs_emit(buf,
+			  "numa_hit %lu\n"
+			  "numa_miss %lu\n"
+			  "numa_foreign %lu\n"
+			  "interleave_hit %lu\n"
+			  "local_node %lu\n"
+			  "other_node %lu\n",
+			  sum_zone_numa_state(dev->id, NUMA_HIT),
+			  sum_zone_numa_state(dev->id, NUMA_MISS),
+			  sum_zone_numa_state(dev->id, NUMA_FOREIGN),
+			  sum_zone_numa_state(dev->id, NUMA_INTERLEAVE_HIT),
+			  sum_zone_numa_state(dev->id, NUMA_LOCAL),
+			  sum_zone_numa_state(dev->id, NUMA_OTHER));
 }
 static DEVICE_ATTR(numastat, S_IRUGO, node_read_numastat, NULL);
 

drivers/base/platform.c

@@ -907,7 +907,7 @@ static ssize_t driver_override_show(struct device *dev,
 	ssize_t len;
 
 	device_lock(dev);
-	len = sprintf(buf, "%s\n", pdev->driver_override);
+	len = sysfs_emit(buf, "%s\n", pdev->driver_override);
 	device_unlock(dev);
 	return len;
 }

drivers/base/power/sysfs.c

@@ -101,7 +101,7 @@ static const char ctrl_on[] = "on";
 static ssize_t control_show(struct device *dev, struct device_attribute *attr,
 			    char *buf)
 {
-	return sprintf(buf, "%s\n",
+	return sysfs_emit(buf, "%s\n",
 				dev->power.runtime_auto ? ctrl_auto : ctrl_on);
 }
 
@@ -127,7 +127,8 @@ static ssize_t runtime_active_time_show(struct device *dev,
 	int ret;
 	spin_lock_irq(&dev->power.lock);
 	update_pm_runtime_accounting(dev);
-	ret = sprintf(buf, "%i\n", jiffies_to_msecs(dev->power.active_jiffies));
+	ret = sysfs_emit(buf, "%i\n",
+			 jiffies_to_msecs(dev->power.active_jiffies));
 	spin_unlock_irq(&dev->power.lock);
 	return ret;
 }
@@ -140,8 +141,8 @@ static ssize_t runtime_suspended_time_show(struct device *dev,
 	int ret;
 	spin_lock_irq(&dev->power.lock);
 	update_pm_runtime_accounting(dev);
-	ret = sprintf(buf, "%i\n",
-		jiffies_to_msecs(dev->power.suspended_jiffies));
+	ret = sysfs_emit(buf, "%i\n",
+			 jiffies_to_msecs(dev->power.suspended_jiffies));
 	spin_unlock_irq(&dev->power.lock);
 	return ret;
 }
@@ -175,7 +176,7 @@ static ssize_t runtime_status_show(struct device *dev,
 			return -EIO;
 		}
 	}
-	return sprintf(buf, p);
+	return sysfs_emit(buf, p);
 }
 
 static DEVICE_ATTR_RO(runtime_status);
@@ -185,7 +186,7 @@ static ssize_t autosuspend_delay_ms_show(struct device *dev,
 {
 	if (!dev->power.use_autosuspend)
 		return -EIO;
-	return sprintf(buf, "%d\n", dev->power.autosuspend_delay);
+	return sysfs_emit(buf, "%d\n", dev->power.autosuspend_delay);
 }
 
 static ssize_t autosuspend_delay_ms_store(struct device *dev,
@@ -214,11 +215,11 @@ static ssize_t pm_qos_resume_latency_us_show(struct device *dev,
 	s32 value = dev_pm_qos_requested_resume_latency(dev);
 
 	if (value == 0)
-		return sprintf(buf, "n/a\n");
+		return sysfs_emit(buf, "n/a\n");
 	if (value == PM_QOS_RESUME_LATENCY_NO_CONSTRAINT)
 		value = 0;
 
-	return sprintf(buf, "%d\n", value);
+	return sysfs_emit(buf, "%d\n", value);
 }
 
 static ssize_t pm_qos_resume_latency_us_store(struct device *dev,
@@ -258,11 +259,11 @@ static ssize_t pm_qos_latency_tolerance_us_show(struct device *dev,
 	s32 value = dev_pm_qos_get_user_latency_tolerance(dev);
 
 	if (value < 0)
-		return sprintf(buf, "auto\n");
+		return sysfs_emit(buf, "auto\n");
 	if (value == PM_QOS_LATENCY_ANY)
-		return sprintf(buf, "any\n");
+		return sysfs_emit(buf, "any\n");
 
-	return sprintf(buf, "%d\n", value);
+	return sysfs_emit(buf, "%d\n", value);
 }
 
 static ssize_t pm_qos_latency_tolerance_us_store(struct device *dev,
@@ -294,8 +295,8 @@ static ssize_t pm_qos_no_power_off_show(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
 {
-	return sprintf(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
-					& PM_QOS_FLAG_NO_POWER_OFF));
+	return sysfs_emit(buf, "%d\n", !!(dev_pm_qos_requested_flags(dev)
+					  & PM_QOS_FLAG_NO_POWER_OFF));
 }
 
 static ssize_t pm_qos_no_power_off_store(struct device *dev,
@@ -323,9 +324,9 @@ static const char _disabled[] = "disabled";
 static ssize_t wakeup_show(struct device *dev, struct device_attribute *attr,
 			   char *buf)
 {
-	return sprintf(buf, "%s\n", device_can_wakeup(dev)
-		? (device_may_wakeup(dev) ? _enabled : _disabled)
-		: "");
+	return sysfs_emit(buf, "%s\n", device_can_wakeup(dev)
+			  ? (device_may_wakeup(dev) ? _enabled : _disabled)
+			  : "");
 }
 
 static ssize_t wakeup_store(struct device *dev, struct device_attribute *attr,
@@ -511,7 +512,7 @@ static DEVICE_ATTR_RO(wakeup_prevent_sleep_time_ms);
 static ssize_t runtime_usage_show(struct device *dev,
 				  struct device_attribute *attr, char *buf)
 {
-	return sprintf(buf, "%d\n", atomic_read(&dev->power.usage_count));
+	return sysfs_emit(buf, "%d\n", atomic_read(&dev->power.usage_count));
 }
 static DEVICE_ATTR_RO(runtime_usage);
 
@@ -519,8 +520,8 @@ static ssize_t runtime_active_kids_show(struct device *dev,
 					struct device_attribute *attr,
 					char *buf)
 {
-	return sprintf(buf, "%d\n", dev->power.ignore_children ?
-		0 : atomic_read(&dev->power.child_count));
+	return sysfs_emit(buf, "%d\n", dev->power.ignore_children ?
+			  0 : atomic_read(&dev->power.child_count));
 }
 static DEVICE_ATTR_RO(runtime_active_kids);
 
@@ -528,12 +529,12 @@ static ssize_t runtime_enabled_show(struct device *dev,
 				    struct device_attribute *attr, char *buf)
 {
 	if (dev->power.disable_depth && (dev->power.runtime_auto == false))
-		return sprintf(buf, "disabled & forbidden\n");
+		return sysfs_emit(buf, "disabled & forbidden\n");
 	if (dev->power.disable_depth)
-		return sprintf(buf, "disabled\n");
+		return sysfs_emit(buf, "disabled\n");
 	if (dev->power.runtime_auto == false)
-		return sprintf(buf, "forbidden\n");
-	return sprintf(buf, "enabled\n");
+		return sysfs_emit(buf, "forbidden\n");
+	return sysfs_emit(buf, "enabled\n");
 }
 static DEVICE_ATTR_RO(runtime_enabled);
 
@@ -541,9 +542,9 @@ static DEVICE_ATTR_RO(runtime_enabled);
 static ssize_t async_show(struct device *dev, struct device_attribute *attr,
 			  char *buf)
 {
-	return sprintf(buf, "%s\n",
-			device_async_suspend_enabled(dev) ?
-				_enabled : _disabled);
+	return sysfs_emit(buf, "%s\n",
+			  device_async_suspend_enabled(dev) ?
+			  _enabled : _disabled);
 }
 
 static ssize_t async_store(struct device *dev, struct device_attribute *attr,

drivers/base/soc.c

@@ -72,13 +72,13 @@ static ssize_t soc_info_get(struct device *dev,
 	struct soc_device *soc_dev = container_of(dev, struct soc_device, dev);
 
 	if (attr == &dev_attr_machine)
-		return sprintf(buf, "%s\n", soc_dev->attr->machine);
+		return sysfs_emit(buf, "%s\n", soc_dev->attr->machine);
 	if (attr == &dev_attr_family)
-		return sprintf(buf, "%s\n", soc_dev->attr->family);
+		return sysfs_emit(buf, "%s\n", soc_dev->attr->family);
 	if (attr == &dev_attr_revision)
-		return sprintf(buf, "%s\n", soc_dev->attr->revision);
+		return sysfs_emit(buf, "%s\n", soc_dev->attr->revision);
 	if (attr == &dev_attr_soc_id)
-		return sprintf(buf, "%s\n", soc_dev->attr->soc_id);
+		return sysfs_emit(buf, "%s\n", soc_dev->attr->soc_id);
 
 	return -EINVAL;