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;
From:   Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To:     linux-integrity@vger.kernel.org
Cc:     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>,
        Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
        stable@vger.kernel.org
Subject: [PATCH v4 2/2] tpm/tpm_i2c_atmel: Return -E2BIG when the transfer is incomplete
Date:   Fri,  8 Feb 2019 20:08:57 +0200
Message-Id: <20190208180857.12330-3-jarkko.sakkinen@linux.intel.com>
In-Reply-To: <20190208180857.12330-1-jarkko.sakkinen@linux.intel.com>
References: <20190208180857.12330-1-jarkko.sakkinen@linux.intel.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Return -E2BIG when the transfer is incomplete. The upper layer does
not retry, so not doing that is incorrect behaviour.

Cc: stable@vger.kernel.org
Fixes: a2871c62e186 ("tpm: Add support for Atmel I2C TPMs")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
---
 drivers/char/tpm/tpm_i2c_atmel.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/char/tpm/tpm_i2c_atmel.c b/drivers/char/tpm/tpm_i2c_atmel.c
index aa11c8a1df5e..8a7e80923091 100644
--- a/drivers/char/tpm/tpm_i2c_atmel.c
+++ b/drivers/char/tpm/tpm_i2c_atmel.c
@@ -69,6 +69,10 @@ static int i2c_atmel_send(struct tpm_chip *chip, u8 *buf, size_t len)
 	if (status < 0)
 		return status;
 
+	/* The upper layer does not support incomplete sends. */
+	if (status != len)
+		return -E2BIG;
+
 	return 0;
 }
 
-- 
2.19.1