Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Date:   Fri, 8 Feb 2019 21:17:10 +0200
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     Stefan Berger <stefanb@linux.ibm.com>
Cc:     linux-integrity@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-security-module@vger.kernel.org,
        Peter Huewe <PeterHuewe@gmx.de>,
        Jason Gunthorpe <jgg@ziepe.ca>,
        Stefan Berger <stefanb@linux.vnet.ibm.com>,
        Alexander Steffen <Alexander.Steffen@infineon.com>,
        stable@vger.kernel.org
Subject: Re: [PATCH v4 1/2] tpm: =?iso-8859-1?Q?Uni?=
 =?iso-8859-1?Q?fy_the_send_callback_behaviour=E4?=
Message-ID: <20190208191710.GA30645@linux.intel.com>
References: <20190208180857.12330-1-jarkko.sakkinen@linux.intel.com>
 <20190208180857.12330-2-jarkko.sakkinen@linux.intel.com>
 <4072b2b6-0f95-be50-0772-7e2869c2c24e@linux.ibm.com>
 <20190208190057.GA3439@linux.intel.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20190208190057.GA3439@linux.intel.com>
Organization: Intel Finland Oy - BIC 0357606-4 - Westendinkatu 7, 02160 Espoo
User-Agent: Mutt/1.10.1 (2018-07-13)
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

On Fri, Feb 08, 2019 at 09:00:57PM +0200, Jarkko Sakkinen wrote:
> It all looks now legit, but just in case I'll add a check for the return
> value to tpm_try_transmit() and a warning if it is not zero in the
> success case (and after that zeroing of rc).

Now the commits are applied both master and next, and these are
the checks for send():

rc = chip->ops->send(chip, buf, count);
if (rc < 0) {
	if (rc != -EPIPE)
		dev_err(&chip->dev,
			"%s: send(): error %d\n", __func__, rc);
	return rc;
}

/* A sanity check. send() should just return zero on success e.g.
 * not the command length.
 */
if (rc > 0) {
	dev_warn(&chip->dev,
		 "%s: send(): invalid value %d\n", __func__, rc);
	rc = 0;
}

Should be fairly safe play now.

/Jarkko