From: James Bottomley <James.Bottomley@HansenPartnership.com>
Date: Thu, 12 Dec 2019 12:58:35 -0500
Subject: security: keys: trusted: fix lost handle flush
Patch-mainline: v5.5-rc3
Git-commit: 45477b3fe3d10376b649b1b85fce72b2f9f1da84
References: jsc#SLE-15209

The original code, before it was moved into security/keys/trusted-keys
had a flush after the blob unseal.  Without that flush, the volatile
handles increase in the TPM until it becomes unusable and the system
either has to be rebooted or the TPM volatile area manually flushed.
Fix by adding back the lost flush, which we now have to export because
of the relocation of the trusted key code may cause the consumer to be
modular.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Fixes: 2e19e10131a0 ("KEYS: trusted: Move TPM2 trusted keys code")
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Acked-by: Lee, Chun-Yi <jlee@suse.com>
---
 drivers/char/tpm/tpm.h                    |    1 -
 drivers/char/tpm/tpm2-cmd.c               |    1 +
 include/linux/tpm.h                       |    1 +
 security/keys/trusted-keys/trusted_tpm2.c |    1 +
 4 files changed, 3 insertions(+), 1 deletion(-)

--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -218,7 +218,6 @@ int tpm2_pcr_read(struct tpm_chip *chip,
 int tpm2_pcr_extend(struct tpm_chip *chip, u32 pcr_idx,
 		    struct tpm_digest *digests);
 int tpm2_get_random(struct tpm_chip *chip, u8 *dest, size_t max);
-void tpm2_flush_context(struct tpm_chip *chip, u32 handle);
 ssize_t tpm2_get_tpm_pt(struct tpm_chip *chip, u32 property_id,
 			u32 *value, const char *desc);
 
--- a/drivers/char/tpm/tpm2-cmd.c
+++ b/drivers/char/tpm/tpm2-cmd.c
@@ -362,6 +362,7 @@ void tpm2_flush_context(struct tpm_chip
 	tpm_transmit_cmd(chip, &buf, 0, "flushing context");
 	tpm_buf_destroy(&buf);
 }
+EXPORT_SYMBOL_GPL(tpm2_flush_context);
 
 struct tpm2_get_cap_out {
 	u8 more_data;
--- a/include/linux/tpm.h
+++ b/include/linux/tpm.h
@@ -403,6 +403,7 @@ extern int tpm_pcr_extend(struct tpm_chi
 extern int tpm_send(struct tpm_chip *chip, void *cmd, size_t buflen);
 extern int tpm_get_random(struct tpm_chip *chip, u8 *data, size_t max);
 extern struct tpm_chip *tpm_default_chip(void);
+void tpm2_flush_context(struct tpm_chip *chip, u32 handle);
 #else
 static inline int tpm_is_tpm2(struct tpm_chip *chip)
 {
--- a/security/keys/trusted-keys/trusted_tpm2.c
+++ b/security/keys/trusted-keys/trusted_tpm2.c
@@ -309,6 +309,7 @@ int tpm2_unseal_trusted(struct tpm_chip
 		return rc;
 
 	rc = tpm2_unseal_cmd(chip, payload, options, blob_handle);
+	tpm2_flush_context(chip, blob_handle);
 
 	return rc;
 }