[PATCH 4.14 099/101] tpm: tpm_try_transmit() refactor error flow.

[Greg Kroah-Hartman]

4.14-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Tomas Winkler <tomas.wink...@intel.com>

commit 01f54664a4db0d612de0ece8e0022f21f9374e9b upstream.

First, rename out_no_locality to out_locality for bailing out on
both tpm_cmd_ready() and tpm_request_locality() failure.
Second, ignore the return value of go_to_idle() as  it may override
the return value of the actual tpm operation, the go_to_idle() error
will be caught on any consequent command.
Last, fix the wrong 'goto out', that jumped back instead of forward.

Cc: sta...@vger.kernel.org
Fixes: 627448e85c76 ("tpm: separate cmd_ready/go_idle from runtime_pm")
Signed-off-by: Tomas Winkler <tomas.wink...@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
Tested-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/char/tpm/tpm-interface.c |   15 ++++++++-------
 1 file changed, 8 insertions(+), 7 deletions(-)

--- a/drivers/char/tpm/tpm-interface.c
+++ b/drivers/char/tpm/tpm-interface.c
@@ -479,13 +479,15 @@ static ssize_t tpm_try_transmit(struct t
 
        if (need_locality) {
                rc = tpm_request_locality(chip, flags);
-               if (rc < 0)
-                       goto out_no_locality;
+               if (rc < 0) {
+                       need_locality = false;
+                       goto out_locality;
+               }
        }
 
        rc = tpm_cmd_ready(chip, flags);
        if (rc)
-               goto out;
+               goto out_locality;
 
        rc = tpm2_prepare_space(chip, space, ordinal, buf);
        if (rc)
@@ -549,14 +551,13 @@ out_recv:
                dev_err(&chip->dev, "tpm2_commit_space: error %d\n", rc);
 
 out:
-       rc = tpm_go_idle(chip, flags);
-       if (rc)
-               goto out;
+       /* may fail but do not override previous error value in rc */
+       tpm_go_idle(chip, flags);
 
+out_locality:
        if (need_locality)
                tpm_relinquish_locality(chip, flags);
 
-out_no_locality:
        if (chip->ops->clk_enable != NULL)
                chip->ops->clk_enable(chip, false);