firmware: use memory_read_from_buffer()

Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: Markus Rechberger <markus.rechberger@amd.com>
Cc: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 9 deletions

diff --git a/drivers/base/firmware_class.c b/drivers/base/firmware_class.c
index b0be1d18fee2..c9c92b00fd55 100644
--- a/drivers/base/firmware_class.c
+++ b/drivers/base/firmware_class.c
@@ -184,7 +184,7 @@ firmware_data_read(struct kobject *kobj, struct bin_attribute *bin_attr,
         struct device *dev = to_dev(kobj);
         struct firmware_priv *fw_priv = dev_get_drvdata(dev);
         struct firmware *fw;
-        ssize_t ret_count = count;
+        ssize_t ret_count;
 
         mutex_lock(&fw_lock);
         fw = fw_priv->fw;
@@ -192,14 +192,8 @@ firmware_data_read(struct kobject *kobj, struct bin_attribute *bin_attr,
                 ret_count = -ENODEV;
                 goto out;
         }
-        if (offset > fw->size) {
-                ret_count = 0;
-                goto out;
-        }
-        if (offset + ret_count > fw->size)
-                ret_count = fw->size - offset;
-
-        memcpy(buffer, fw->data + offset, ret_count);
+        ret_count = memory_read_from_buffer(buffer, count, &offset,
+                                                fw->data, fw->size);
 out:
         mutex_unlock(&fw_lock);
         return ret_count;