Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Date:   Mon, 1 Mar 2021 11:48:39 +0200
From:   Jarkko Sakkinen <jarkko@kernel.org>
To:     Dinghao Liu <dinghao.liu@zju.edu.cn>
Cc:     kjlu@umn.edu, Peter Huewe <peterhuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] tpm: Add missing check in tpm_inf_recv
Message-ID: <YDy4d5qO8MrNwImx@kernel.org>
References: <20210228093230.5676-1-dinghao.liu@zju.edu.cn>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20210228093230.5676-1-dinghao.liu@zju.edu.cn>
Precedence: bulk

On Sun, Feb 28, 2021 at 05:32:30PM +0800, Dinghao Liu wrote:
> The use of wait() in tpm_inf_recv() is almost the same. It's odd that
> we only check the return value and terminate execution flow of one call.
> 
> Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>

Is the unchecked return value of wait() the problem? I don't see the
function even mentioned in the description.

/Jarkko

> ---
>  drivers/char/tpm/tpm_infineon.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/char/tpm/tpm_infineon.c b/drivers/char/tpm/tpm_infineon.c
> index 9c924a1440a9..abe00f45aa45 100644
> --- a/drivers/char/tpm/tpm_infineon.c
> +++ b/drivers/char/tpm/tpm_infineon.c
> @@ -263,7 +263,9 @@ static int tpm_inf_recv(struct tpm_chip *chip, u8 * buf, size_t count)
>  		size = ((buf[2] << 8) | buf[3]);
>  
>  		for (i = 0; i < size; i++) {
> -			wait(chip, STAT_RDA);
> +			ret = wait(chip, STAT_RDA);
> +			if (ret)
> +				return -EIO;
>  			buf[i] = tpm_data_in(RDFIFO);
>  		}
>  
> -- 
> 2.17.1
> 
>