crypto: keembay - use 64-bit arithmetic for computing bit_len

src_size and aad_size are defined as u32, so the following expressions are
currently being evaluated using 32-bit arithmetic:

bit_len = src_size * 8;
...
bit_len = aad_size * 8;

However, bit_len is used afterwards in a context that expects a valid
64-bit value (the lower and upper 32-bit words of bit_len are extracted
and written to hw).

In order to make sure the correct bit length is generated and the 32-bit
multiplication does not wrap around, cast src_size and aad_size to u64.

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Acked-by: Daniele Alessandrelli <daniele.alessandrelli@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/keembay/ocs-aes.c b/drivers/crypto/keembay/ocs-aes.c
index cc286ad..b85c894 100644 (file)
--- a/drivers/crypto/keembay/ocs-aes.c
+++ b/drivers/crypto/keembay/ocs-aes.c
@@ -958,14 +958,14 @@ int ocs_aes_gcm_op(struct ocs_aes_dev *aes_dev,
        ocs_aes_write_last_data_blk_len(aes_dev, src_size);
 
        /* Write ciphertext bit length */
-       bit_len = src_size * 8;
+       bit_len = (u64)src_size * 8;
        val = bit_len & 0xFFFFFFFF;
        iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_0_OFFSET);
        val = bit_len >> 32;
        iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_1_OFFSET);
 
        /* Write aad bit length */
-       bit_len = aad_size * 8;
+       bit_len = (u64)aad_size * 8;
        val = bit_len & 0xFFFFFFFF;
        iowrite32(val, aes_dev->base_reg + AES_MULTIPURPOSE2_2_OFFSET);
        val = bit_len >> 32;