From: Martin Schwidefsky <schwidefsky@de.ibm.com>
Subject: Re: [patch] s390/crypto: unlock on error in prng_tdes_read()
Date: Fri, 18 Nov 2016 13:12:47 +0100
Message-ID: <20161118131247.44a52270@mschwide>
References: <20161118105451.GA26523@mwanda>
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Cc: Herbert Xu <herbert@gondor.apana.org.au>,
        Harald Freudenberger <freude@linux.vnet.ibm.com>,
        "David S. Miller" <davem@davemloft.net>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        linux-crypto@vger.kernel.org, linux-s390@vger.kernel.org,
        kernel-janitors@vger.kernel.org
To: Dan Carpenter <dan.carpenter@oracle.com>
Return-path: <kernel-janitors-owner@vger.kernel.org>
In-Reply-To: <20161118105451.GA26523@mwanda>
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On Fri, 18 Nov 2016 14:11:00 +0300
Dan Carpenter <dan.carpenter@oracle.com> wrote:

> We added some new locking but forgot to unlock on error.
> 
> Fixes: 57127645d79d ("s390/zcrypt: Introduce new SHA-512 based Pseudo Random Generator.")
> Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
> 
> diff --git a/arch/s390/crypto/prng.c b/arch/s390/crypto/prng.c
> index 9cc050f..1113389 100644
> --- a/arch/s390/crypto/prng.c
> +++ b/arch/s390/crypto/prng.c
> @@ -507,8 +507,10 @@ static ssize_t prng_tdes_read(struct file *file, char __user *ubuf,
>  		prng_data->prngws.byte_counter += n;
>  		prng_data->prngws.reseed_counter += n;
> 
> -		if (copy_to_user(ubuf, prng_data->buf, chunk))
> -			return -EFAULT;
> +		if (copy_to_user(ubuf, prng_data->buf, chunk)) {
> +			ret = -EFAULT;
> +			break;
> +		}
> 
>  		nbytes -= chunk;
>  		ret += chunk;
> 

Nice spotting, I will add this to my fixes tree. Thank you..

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.