eCryptfs: fix 32 bit corruption issue
eCryptfs: fix 32 bit corruption issue

Shifting page->index on 32 bit systems was overflowing, causing
data corruption of > 4GB files. Fix this by casting it first.

https://launchpad.net/bugs/1243636

Signed-off-by: Colin Ian King <d100aa70785e45ee8deab668147d941941915c21@canonical.com>
Reported-by: Lars Duesing <f04be08b77a9a94278b5c488d59aa646aa558f3b@camelotsweb.de>
Cc: 4fbacc2fa0ffdbb11bf1ad6925b886ebd08dd15f@vger.kernel.org # v3.11+
Signed-off-by: Tyler Hicks <93eeee00a2beb1fbd6106ad8f59025f171ca91c6@canonical.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs