Re: [PATCH 2/2] crypto: chcr - Fix error checking

From: Dan Carpenter
Date: Thu Apr 13 2017 - 10:04:37 EST


On Thu, Apr 13, 2017 at 02:14:30PM +0200, Christophe JAILLET wrote:
> If 'chcr_alloc_shash()' a few lines above fails, 'base_hash' can be an
> error pointer when we 'goto out'.
> So checking for NULL here is not enough because it is likely that
> 'chcr_free_shash' will crash if we pass an error pointer.
>
> Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
> ---
> Another solution, amybe safer, would be to instrument 'chcr_free_shash' or
> 'crypto_free_shash' to accept an error pointer and return immediatelly in
> such a case.
> ---
> drivers/crypto/chelsio/chcr_algo.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/crypto/chelsio/chcr_algo.c b/drivers/crypto/chelsio/chcr_algo.c
> index f19590ac8775..41750b97f43c 100644
> --- a/drivers/crypto/chelsio/chcr_algo.c
> +++ b/drivers/crypto/chelsio/chcr_algo.c
> @@ -2351,7 +2351,7 @@ static int chcr_authenc_setkey(struct crypto_aead *authenc, const u8 *key,
> }
> out:
> aeadctx->enckey_len = 0;
> - if (base_hash)
> + if (!IS_ERR_OR_NULL(base_hash))
> chcr_free_shash(base_hash);

Ah... Ok. Fine, but redo the first patch anyway because it shouldn't
ever be NULL.

regards,
dan carpenter