diff --git a/fs/ecryptfs/inode.c b/fs/ecryptfs/inode.c
index c92cc1c00aae9a845911011f091480d9cbe4ffca..7315547193ea7e832f9de89f29d6545a1ec720ee 100644
--- a/fs/ecryptfs/inode.c
+++ b/fs/ecryptfs/inode.c
@@ -31,6 +31,7 @@
 #include <linux/mount.h>
 #include <linux/crypto.h>
 #include <linux/fs_stack.h>
+#include <asm/unaligned.h>
 #include "ecryptfs_kernel.h"
 
 static struct dentry *lock_parent(struct dentry *dentry)
@@ -364,8 +365,7 @@ static struct dentry *ecryptfs_lookup(struct inode *dir, struct dentry *dentry,
 		else
 			file_size = i_size_read(lower_dentry->d_inode);
 	} else {
-		memcpy(&file_size, page_virt, sizeof(file_size));
-		file_size = be64_to_cpu(file_size);
+		file_size = get_unaligned_be64(page_virt);
 	}
 	i_size_write(dentry->d_inode, (loff_t)file_size);
 	kmem_cache_free(ecryptfs_header_cache_2, page_virt);
diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 2b6fe1e6e8ba38d85f5e6b16e63bd8d55804a35a..245c2dc02d5cfa96d1fe60818ae849555ef5e991 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -32,6 +32,7 @@
 #include <linux/file.h>
 #include <linux/crypto.h>
 #include <linux/scatterlist.h>
+#include <asm/unaligned.h>
 #include "ecryptfs_kernel.h"
 
 /**
@@ -372,7 +373,6 @@ static int ecryptfs_prepare_write(struct file *file, struct page *page,
  */
 static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode)
 {
-	u64 file_size;
 	char *file_size_virt;
 	int rc;
 
@@ -381,9 +381,7 @@ static int ecryptfs_write_inode_size_to_header(struct inode *ecryptfs_inode)
 		rc = -ENOMEM;
 		goto out;
 	}
-	file_size = (u64)i_size_read(ecryptfs_inode);
-	file_size = cpu_to_be64(file_size);
-	memcpy(file_size_virt, &file_size, sizeof(u64));
+	put_unaligned_be64(i_size_read(ecryptfs_inode), file_size_virt);
 	rc = ecryptfs_write_lower(ecryptfs_inode, file_size_virt, 0,
 				  sizeof(u64));
 	kfree(file_size_virt);
@@ -403,7 +401,6 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
 	struct dentry *lower_dentry =
 		ecryptfs_inode_to_private(ecryptfs_inode)->lower_file->f_dentry;
 	struct inode *lower_inode = lower_dentry->d_inode;
-	u64 file_size;
 	int rc;
 
 	if (!lower_inode->i_op->getxattr || !lower_inode->i_op->setxattr) {
@@ -424,9 +421,7 @@ static int ecryptfs_write_inode_size_to_xattr(struct inode *ecryptfs_inode)
 					   xattr_virt, PAGE_CACHE_SIZE);
 	if (size < 0)
 		size = 8;
-	file_size = (u64)i_size_read(ecryptfs_inode);
-	file_size = cpu_to_be64(file_size);
-	memcpy(xattr_virt, &file_size, sizeof(u64));
+	put_unaligned_be64(i_size_read(ecryptfs_inode), xattr_virt);
 	rc = lower_inode->i_op->setxattr(lower_dentry, ECRYPTFS_XATTR_NAME,
 					 xattr_virt, size, 0);
 	mutex_unlock(&lower_inode->i_mutex);