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
[ Brennan : Regenerated for 4.19 to fix CVE-2022-20166 ]
Signed-off-by: Brennan Lamoreaux <blamoreaux@vmware.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 9 insertions, 9 deletions

diff --git a/drivers/base/cacheinfo.c b/drivers/base/cacheinfo.c
index ce015ce2977c..51eb403f89de 100644
--- a/drivers/base/cacheinfo.c
+++ b/drivers/base/cacheinfo.c
@@ -372,7 +372,7 @@ 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)
@@ -402,11 +402,11 @@ 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;
 	}
@@ -420,11 +420,11 @@ 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;
 }
 
@@ -436,9 +436,9 @@ 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;
 }