NTFS: Fix a potential overflow by casting (index + 1) to s64 before doing a

      left shift using PAGE_CACHE_SHIFT in fs/ntfs/file.c.  Thanks to Andrew
      Morton pointing this out to.

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

1 files changed, 1 insertions, 1 deletions

diff --git a/fs/ntfs/file.c b/fs/ntfs/file.c
index 727533891813..c73c8864cbad 100644
--- a/fs/ntfs/file.c
+++ b/fs/ntfs/file.c
@@ -248,7 +248,7 @@ do_non_resident_extend:
                  * enough to make ntfs_writepage() work.
                  */
                 write_lock_irqsave(&ni->size_lock, flags);
-                ni->initialized_size = (index + 1) << PAGE_CACHE_SHIFT;
+                ni->initialized_size = (s64)(index + 1) << PAGE_CACHE_SHIFT;
                 if (ni->initialized_size > new_init_size)
                         ni->initialized_size = new_init_size;
                 write_unlock_irqrestore(&ni->size_lock, flags);