On 3 October 2018 at 07:22, Eric Biggers <ebiggers@xxxxxxxxxx> wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> In the new arm64 CTS-CBC implementation, return an error code rather
> than crashing on inputs shorter than AES_BLOCK_SIZE bytes. Also set
> cra_blocksize to AES_BLOCK_SIZE (like is done in the cts template) to
> indicate the minimum input size.
>
> Fixes: dd597fb33ff0 ("crypto: arm64/aes-blk - add support for CTS-CBC mode")
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Thanks Eric
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
> ---
> arch/arm64/crypto/aes-glue.c | 13 +++++++++----
> 1 file changed, 9 insertions(+), 4 deletions(-)
>
> diff --git a/arch/arm64/crypto/aes-glue.c b/arch/arm64/crypto/aes-glue.c
> index 26d2b0263ba63..1e676625ef33f 100644
> --- a/arch/arm64/crypto/aes-glue.c
> +++ b/arch/arm64/crypto/aes-glue.c
> @@ -243,8 +243,11 @@ static int cts_cbc_encrypt(struct skcipher_request *req)
>
> skcipher_request_set_tfm(&rctx->subreq, tfm);
>
> - if (req->cryptlen == AES_BLOCK_SIZE)
> + if (req->cryptlen <= AES_BLOCK_SIZE) {
> + if (req->cryptlen < AES_BLOCK_SIZE)
> + return -EINVAL;
> cbc_blocks = 1;
> + }
>
> if (cbc_blocks > 0) {
> unsigned int blocks;
> @@ -305,8 +308,11 @@ static int cts_cbc_decrypt(struct skcipher_request *req)
>
> skcipher_request_set_tfm(&rctx->subreq, tfm);
>
> - if (req->cryptlen == AES_BLOCK_SIZE)
> + if (req->cryptlen <= AES_BLOCK_SIZE) {
> + if (req->cryptlen < AES_BLOCK_SIZE)
> + return -EINVAL;
> cbc_blocks = 1;
> + }
>
> if (cbc_blocks > 0) {
> unsigned int blocks;
> @@ -486,14 +492,13 @@ static struct skcipher_alg aes_algs[] = { {
> .cra_driver_name = "__cts-cbc-aes-" MODE,
> .cra_priority = PRIO,
> .cra_flags = CRYPTO_ALG_INTERNAL,
> - .cra_blocksize = 1,
> + .cra_blocksize = AES_BLOCK_SIZE,
> .cra_ctxsize = sizeof(struct crypto_aes_ctx),
> .cra_module = THIS_MODULE,
> },
> .min_keysize = AES_MIN_KEY_SIZE,
> .max_keysize = AES_MAX_KEY_SIZE,
> .ivsize = AES_BLOCK_SIZE,
> - .chunksize = AES_BLOCK_SIZE,
> .walksize = 2 * AES_BLOCK_SIZE,
> .setkey = skcipher_aes_setkey,
> .encrypt = cts_cbc_encrypt,
> --
> 2.19.0
>
