eCryptfs: fix data types

Update data types and add casts in order to avoid potential overflow
issues.

Signed-off-by: Michael Halcrow <mhalcrow@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 3 insertions, 2 deletions

diff --git a/fs/ecryptfs/mmap.c b/fs/ecryptfs/mmap.c
index 9bc707df3b60..6ae0afb238d1 100644
--- a/fs/ecryptfs/mmap.c
+++ b/fs/ecryptfs/mmap.c
@@ -286,7 +286,8 @@ ecryptfs_copy_up_encrypted_with_header(struct page *page,
         int rc = 0;
 
         while (extent_num_in_page < num_extents_per_page) {
-                loff_t view_extent_num = ((page->index * num_extents_per_page)
+                loff_t view_extent_num = ((((loff_t)page->index)
+                                           * num_extents_per_page)
                                           + extent_num_in_page);
 
                 if (view_extent_num < crypt_stat->num_header_extents_at_front) {
@@ -706,7 +707,7 @@ static int ecryptfs_commit_write(struct file *file, struct page *page,
                                 "index [0x%.16x])\n", page->index);
                 goto out;
         }
-        pos = (page->index << PAGE_CACHE_SHIFT) + to;
+        pos = (((loff_t)page->index) << PAGE_CACHE_SHIFT) + to;
         if (pos > i_size_read(ecryptfs_inode)) {
                 i_size_write(ecryptfs_inode, pos);
                 ecryptfs_printk(KERN_DEBUG, "Expanded file size to "