commit 442601e87a4769a8daba4976ec3afa5222ca211d upstream

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 Reviewed-by: Jerry Snitselaar jsnitsel@redhat.com --- backport v4.4.178 drivers/char/tpm/tpm_i2c_atmel.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm_i2c_atmel.c b/drivers/char/tpm/tpm_i2c_atmel.c index 95ce2e9ccdc6..cc4e642d3180 100644 --- a/drivers/char/tpm/tpm_i2c_atmel.c +++ b/drivers/char/tpm/tpm_i2c_atmel.c @@ -65,7 +65,15 @@ static int i2c_atmel_send(struct tpm_chip *chip, u8 *buf, size_t len) dev_dbg(&chip->dev, "%s(buf=%*ph len=%0zx) -> sts=%d\n", __func__, (int)min_t(size_t, 64, len), buf, len, status); - return status; + + if (status < 0) + return status; + + /* The upper layer does not support incomplete sends. */ + if (status != len) + return -E2BIG; + + return 0; }

static int i2c_atmel_recv(struct tpm_chip *chip, u8 *buf, size_t count)