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

commit aa838896d87af561a33ecefea1caa4c15a68bc47 upstream.

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: Joe Perches <joe@perches.com>
Link: https://lore.kernel.org/r/3d033c33056d88bbe34d4ddb62afd05ee166ab9a.1600285923.git.joe@perches.com
Cc: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Bug: 182388481
[only the wakeup_stats.c portion - gregkh]
(cherry picked from commit aa838896d87af561a33ecefea1caa4c15a68bc47)
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>
Change-Id: Ib6f1e608caae694532cfef2ab43092274630fb54
Signed-off-by: Greg Kroah-Hartman <gregkh@google.com>

drivers/base/power/wakeup_stats.c

@@ -42,7 +42,7 @@ static ssize_t active_time_ms_show(struct device *dev,
 	ktime_t active_time =
 		ws->active ? ktime_sub(ktime_get(), ws->last_time) : 0;
 
-	return sprintf(buf, "%lld\n", ktime_to_ms(active_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(active_time));
 }
 static DEVICE_ATTR_RO(active_time_ms);
 
@@ -57,7 +57,7 @@ static ssize_t total_time_ms_show(struct device *dev,
 		active_time = ktime_sub(ktime_get(), ws->last_time);
 		total_time = ktime_add(total_time, active_time);
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(total_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(total_time));
 }
 static DEVICE_ATTR_RO(total_time_ms);
 
@@ -73,7 +73,7 @@ static ssize_t max_time_ms_show(struct device *dev,
 		if (active_time > max_time)
 			max_time = active_time;
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(max_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(max_time));
 }
 static DEVICE_ATTR_RO(max_time_ms);
 
@@ -82,7 +82,7 @@ static ssize_t last_change_ms_show(struct device *dev,
 {
 	struct wakeup_source *ws = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%lld\n", ktime_to_ms(ws->last_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(ws->last_time));
 }
 static DEVICE_ATTR_RO(last_change_ms);
 
@@ -91,7 +91,7 @@ static ssize_t name_show(struct device *dev, struct device_attribute *attr,
 {
 	struct wakeup_source *ws = dev_get_drvdata(dev);
 
-	return sprintf(buf, "%s\n", ws->name);
+	return sysfs_emit(buf, "%s\n", ws->name);
 }
 static DEVICE_ATTR_RO(name);
 
@@ -106,7 +106,7 @@ static ssize_t prevent_suspend_time_ms_show(struct device *dev,
 		prevent_sleep_time = ktime_add(prevent_sleep_time,
 			ktime_sub(ktime_get(), ws->start_prevent_time));
 	}
-	return sprintf(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
+	return sysfs_emit(buf, "%lld\n", ktime_to_ms(prevent_sleep_time));
 }
 static DEVICE_ATTR_RO(prevent_suspend_time_ms);