Get a reference to the TPM chip on every call to tpm_try_get_ops() and release the reference in tpm_put_ops().
Signed-off-by: Stefan Berger <[email protected]> --- drivers/char/tpm/tpm-chip.c | 5 ++++- include/linux/tpm.h | 4 ++++ 2 files changed, 8 insertions(+), 1 deletion(-) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index a933676194a4..23b667c730f6 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -58,6 +58,8 @@ int tpm_try_get_ops(struct tpm_chip *chip) if (!chip->ops) goto out_lock; + kref_get(&chip->kref); + return 0; out_lock: up_read(&chip->ops_sem); @@ -77,6 +79,7 @@ void tpm_put_ops(struct tpm_chip *chip) { up_read(&chip->ops_sem); put_device(&chip->dev); + tpm_chip_put(chip); } EXPORT_SYMBOL_GPL(tpm_put_ops); @@ -129,7 +132,7 @@ static void tpm_chip_free(struct kref *kref) kfree(chip); } -static void tpm_chip_put(struct tpm_chip *chip) +void tpm_chip_put(struct tpm_chip *chip) { if (chip) kref_put(&chip->kref, tpm_chip_free); diff --git a/include/linux/tpm.h b/include/linux/tpm.h index 06639fb6ab85..cdb3ecdfc933 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -61,6 +61,7 @@ extern int tpm_seal_trusted(struct tpm_chip *chip, extern int tpm_unseal_trusted(struct tpm_chip *chip, struct trusted_key_payload *payload, struct trusted_key_options *options); +extern void tpm_chip_put(struct tpm_chip *chip); #else static inline int tpm_is_tpm2(struct tpm_chip *chip) { @@ -96,5 +97,8 @@ static inline int tpm_unseal_trusted(struct tpm_chip *chip, { return -ENODEV; } +static inline void tpm_chip_put(struct tpm_chip *chip) +{ +} #endif #endif -- 2.13.6
