tpm/tpm_i2c_stm_st33: Add status check when reading data on the FIFO

Add a return value check when reading data from the FIFO register.

Cc: <stable@vger.kernel.org>
Reviewed-by: Jason Gunthorpe <jason.gunthorpe@obsidianresearch.com>
Signed-off-by: Christophe Ricard <christophe-h.ricard@st.com>
Reviewed-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Peter Huewe <peterhuewe@gmx.de>

diff --git a/drivers/char/tpm/tpm_i2c_stm_st33.c b/drivers/char/tpm/tpm_i2c_stm_st33.c
index 48c4808..4f70296 100644 (file)
--- a/drivers/char/tpm/tpm_i2c_stm_st33.c
+++ b/drivers/char/tpm/tpm_i2c_stm_st33.c
@@ -441,7 +441,7 @@ again:
  */
 static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
 {
-       int size = 0, burstcnt, len;
+       int size = 0, burstcnt, len, ret;
        struct tpm_stm_dev *tpm_dev;
 
        tpm_dev = (struct tpm_stm_dev *)TPM_VPRIV(chip);
@@ -455,7 +455,10 @@ static int recv_data(struct tpm_chip *chip, u8 *buf, size_t count)
                if (burstcnt < 0)
                        return burstcnt;
                len = min_t(int, burstcnt, count - size);
-               I2C_READ_DATA(tpm_dev, TPM_DATA_FIFO, buf + size, len);
+               ret = I2C_READ_DATA(tpm_dev, TPM_DATA_FIFO, buf + size, len);
+               if (ret < 0)
+                       return ret;
+
                size += len;
        }
        return size;