Re: [PATCH] crypto: caam - fix use after free issue in *_crypt_done

[Iuliana Prodan]

On 4/28/2020 8:14 AM, Zhenzhong Duan wrote:
> In both aead_crypt_done and skcipher_crypt_done, edesc->bklog is
> referenced after the structure pointed by edesc is freed.
> 
> Fix them by moving kfree(edesc) to the end of function call.
> 
> Signed-off-by: Zhenzhong Duan <zhenzhong.duan@xxxxxxxxx>

These issues were already fixed, and applied on cryptodev, by this 
series: https://patchwork.kernel.org/cover/11476799/

Regards,
Iulia

> ---
>   drivers/crypto/caam/caamalg.c | 8 ++++----
>   1 file changed, 4 insertions(+), 4 deletions(-)
> 
> diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c
> index b7bb7c30adeb..6d746ef5e650 100644
> --- a/drivers/crypto/caam/caamalg.c
> +++ b/drivers/crypto/caam/caamalg.c
> @@ -973,8 +973,6 @@ static void aead_crypt_done(struct device *jrdev, u32 *desc, u32 err,
>   
>   	aead_unmap(jrdev, edesc, req);
>   
> -	kfree(edesc);
> -
>   	/*
>   	 * If no backlog flag, the completion of the request is done
>   	 * by CAAM, not crypto engine.
> @@ -983,6 +981,8 @@ static void aead_crypt_done(struct device *jrdev, u32 *desc, u32 err,
>   		aead_request_complete(req, ecode);
>   	else
>   		crypto_finalize_aead_request(jrp->engine, req, ecode);
> +
> +	kfree(edesc);
>   }
>   
>   static void skcipher_crypt_done(struct device *jrdev, u32 *desc, u32 err,
> @@ -1022,8 +1022,6 @@ static void skcipher_crypt_done(struct device *jrdev, u32 *desc, u32 err,
>   		     DUMP_PREFIX_ADDRESS, 16, 4, req->dst,
>   		     edesc->dst_nents > 1 ? 100 : req->cryptlen, 1);
>   
> -	kfree(edesc);
> -
>   	/*
>   	 * If no backlog flag, the completion of the request is done
>   	 * by CAAM, not crypto engine.
> @@ -1032,6 +1030,8 @@ static void skcipher_crypt_done(struct device *jrdev, u32 *desc, u32 err,
>   		skcipher_request_complete(req, ecode);
>   	else
>   		crypto_finalize_skcipher_request(jrp->engine, req, ecode);
> +
> +	kfree(edesc);
>   }
>   
>   /*
>