tpm: Clean up TPM space after command failure

[ Upstream commit e3aaebcbb7c6b403416f442d1de70d437ce313a7 ]

tpm_dev_transmit prepares the TPM space before attempting command
transmission. However if the command fails no rollback of this
preparation is done. This can result in transient handles being leaked
if the device is subsequently closed with no further commands performed.

Fix this by flushing the space in the event of command transmission
failure.

Fixes: 745b361e989a ("tpm: infrastructure for TPM spaces")
Signed-off-by: Jonathan McDowell <noodles@meta.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-common.c
index 30b4c288c1bbc3ba4dfedd38abf9663ace12e819..c3fbbf4d3db79a9b4523611aecc6772bcddffed8 100644 (file)
--- a/drivers/char/tpm/tpm-dev-common.c
+++ b/drivers/char/tpm/tpm-dev-common.c
@@ -47,6 +47,8 @@ static ssize_t tpm_dev_transmit(struct tpm_chip *chip, struct tpm_space *space,
 
        if (!ret)
                ret = tpm2_commit_space(chip, space, buf, &len);
+       else
+               tpm2_flush_space(chip);
 
 out_rc:
        return ret ? ret : len;

diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index 363afdd4d1d30635e2e2e07d8cd136870dc82889..d4d1007fe8117e3c2f11c974b041bddcb1d553f5 100644 (file)
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -166,6 +166,9 @@ void tpm2_flush_space(struct tpm_chip *chip)
        struct tpm_space *space = &chip->work_space;
        int i;
 
+       if (!space)
+               return;
+
        for (i = 0; i < ARRAY_SIZE(space->context_tbl); i++)
                if (space->context_tbl[i] && ~space->context_tbl[i])
                        tpm2_flush_context(chip, space->context_tbl[i]);