[PATCH] tpm: fix unused-value issues in tpm_try_transmit

From: Gustavo A. R. Silva
Date: Wed Oct 10 2018 - 09:38:44 EST


Currently, there are some values assigned to variable *rc*, which
are never actually used in any computation, because such variable
is updated at line 550, before they can be used:

549out:
550 rc = tpm_go_idle(chip, flags);
551 if (rc)
552 goto out;

Fix this by removing such assignments.

Addresses-Coverity-ID: 1470245 ("Unused value")
Addresses-Coverity-ID: 1470250 ("Unused value")
Addresses-Coverity-ID: 1470251 ("Unused value")
Fixes: 627448e85c76 ("tpm: separate cmd_ready/go_idle from runtime_pm")
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
---
drivers/char/tpm/tpm-interface.c | 8 ++------
1 file changed, 2 insertions(+), 6 deletions(-)

diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interface.c
index 129f640..8062736 100644
--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -512,7 +512,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,

if (chip->ops->req_canceled(chip, status)) {
dev_err(&chip->dev, "Operation Canceled\n");
- rc = -ECANCELED;
goto out;
}

@@ -522,7 +521,6 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,

chip->ops->cancel(chip);
dev_err(&chip->dev, "Operation Timed out\n");
- rc = -ETIME;
goto out;

out_recv:
@@ -533,14 +531,12 @@ static ssize_t tpm_try_transmit(struct tpm_chip *chip,
"tpm_transmit: tpm_recv: error %d\n", rc);
goto out;
} else if (len < TPM_HEADER_SIZE) {
- rc = -EFAULT;
goto out;
}

- if (len != be32_to_cpu(header->length)) {
- rc = -EFAULT;
+ if (len != be32_to_cpu(header->length))
goto out;
- }
+

rc = tpm2_commit_space(chip, space, ordinal, buf, &len);
if (rc)
--
2.7.4