From: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx> commit 513253f8c293c0c8bd46d09d337fc892bf8f9f48 upstream. recv_data either returns the number of received bytes, or a negative value representing an error code. Adding the return value directly to the total number of received bytes therefore looks a little weird, since it might add a negative error code to a sum of bytes. The following check for size < expected usually makes the function return ETIME in that case, so it does not cause too many problems in practice. But to make the code look cleaner and because the caller might still be interested in the original error code, explicitly check for the presence of an error code and pass that through. Cc: stable@xxxxxxxxxxxxxxx Fixes: cb5354253af2 ("[PATCH] tpm: spacing cleanups 2") Signed-off-by: Alexander Steffen <Alexander.Steffen@xxxxxxxxxxxx> Reviewed-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> Signed-off-by: Jarkko Sakkinen <jarkko@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/char/tpm/tpm_tis_core.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-) --- a/drivers/char/tpm/tpm_tis_core.c +++ b/drivers/char/tpm/tpm_tis_core.c @@ -314,6 +314,7 @@ static int tpm_tis_recv(struct tpm_chip int size = 0; int status; u32 expected; + int rc; if (count < TPM_HEADER_SIZE) { size = -EIO; @@ -333,8 +334,13 @@ static int tpm_tis_recv(struct tpm_chip goto out; } - size += recv_data(chip, &buf[TPM_HEADER_SIZE], - expected - TPM_HEADER_SIZE); + rc = recv_data(chip, &buf[TPM_HEADER_SIZE], + expected - TPM_HEADER_SIZE); + if (rc < 0) { + size = rc; + goto out; + } + size += rc; if (size < expected) { dev_err(&chip->dev, "Unable to read remainder of result\n"); size = -ETIME;