1 files changed, 73 insertions, 1 deletions

diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index ba3650d03c48..3386014becc6 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -260,6 +260,33 @@ out:
                 ClearPageUptodate(page);
         return rc;
 }
+/**
+ *   Header Extent:
+ *     Octets 0-7:        Unencrypted file size (big-endian)
+ *     Octets 8-15:       eCryptfs special marker
+ *     Octets 16-19:      Flags
+ *      Octet 16:         File format version number (between 0 and 255)
+ *      Octets 17-18:     Reserved
+ *      Octet 19:         Bit 1 (lsb): Reserved
+ *                        Bit 2: Encrypted?
+ *                        Bits 3-8: Reserved
+ *     Octets 20-23:      Header extent size (big-endian)
+ *     Octets 24-25:      Number of header extents at front of file
+ *                        (big-endian)
+ *     Octet  26:         Begin RFC 2440 authentication token packet set
+ */
+static void set_header_info(char *page_virt,
+                            struct ecryptfs_crypt_stat *crypt_stat)
+{
+        size_t written;
+        int save_num_header_extents_at_front =
+                crypt_stat->num_header_extents_at_front;
+
+        crypt_stat->num_header_extents_at_front = 1;
+        ecryptfs_write_header_metadata(page_virt + 20, crypt_stat, &written);
+        crypt_stat->num_header_extents_at_front =
+                save_num_header_extents_at_front;
+}
 
 /**
  * ecryptfs_readpage
@@ -289,10 +316,55 @@ static int ecryptfs_readpage(struct file *file, struct page *page)
                                         "[%d]\n", rc);
                         goto out;
                 }
+        } else if (crypt_stat->flags & ECRYPTFS_VIEW_AS_ENCRYPTED) {
+                if (crypt_stat->flags & ECRYPTFS_METADATA_IN_XATTR) {
+                        int num_pages_in_header_region =
+                                (crypt_stat->header_extent_size
+                                 / PAGE_CACHE_SIZE);
+
+                        if (page->index < num_pages_in_header_region) {
+                                char *page_virt;
+
+                                page_virt = (char *)kmap(page);
+                                if (!page_virt) {
+                                        rc = -ENOMEM;
+                                        printk(KERN_ERR "Error mapping page\n");
+                                        goto out;
+                                }
+                                memset(page_virt, 0, PAGE_CACHE_SIZE);
+                                if (page->index == 0) {
+                                        rc = ecryptfs_read_xattr_region(
+                                                page_virt, file->f_path.dentry);
+                                        set_header_info(page_virt, crypt_stat);
+                                }
+                                kunmap(page);
+                                if (rc) {
+                                        printk(KERN_ERR "Error reading xattr "
+                                               "region\n");
+                                        goto out;
+                                }
+                        } else {
+                                rc = ecryptfs_do_readpage(
+                                        file, page,
+                                        (page->index
+                                         - num_pages_in_header_region));
+                                if (rc) {
+                                        printk(KERN_ERR "Error reading page; "
+                                               "rc = [%d]\n", rc);
+                                        goto out;
+                                }
+                        }
+                } else {
+                        rc = ecryptfs_do_readpage(file, page, page->index);
+                        if (rc) {
+                                printk(KERN_ERR "Error reading page; rc = "
+                                       "[%d]\n", rc);
+                                goto out;
+                        }
+                }
         } else {
                 rc = ecryptfs_decrypt_page(file, page);
                 if (rc) {
-
                         ecryptfs_printk(KERN_ERR, "Error decrypting page; "
                                         "rc = [%d]\n", rc);
                         goto out;