tree bc57636479d687c706c17d6818e9593b498c7f9d
parent d041b557792c85677f17e08eee535eafbd6b9aa2
author Romain Izard <romain.izard.pro@gmail.com> 1509460955 +0100
committer Herbert Xu <herbert@gondor.apana.org.au> 1509716135 +0800

crypto: ccm - preserve the IV buffer

The IV buffer used during CCM operations is used twice, during both the
hashing step and the ciphering step.

When using a hardware accelerator that updates the contents of the IV
buffer at the end of ciphering operations, the value will be modified.
In the decryption case, the subsequent setup of the hashing algorithm
will interpret the updated IV instead of the original value, which can
lead to out-of-bounds writes.

Reuse the idata buffer, only used in the hashing step, to preserve the
IV's value during the ciphering step in the decryption case.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>