Commit 6c4e79d9 authored by Jarkko Sakkinen's avatar Jarkko Sakkinen
Browse files

tpm: Unify the mismatching TPM space buffer sizes 



The size of the buffers for storing context's and sessions can vary from
arch to arch as PAGE_SIZE can be anything between 4 kB and 256 kB (the
maximum for PPC64). Define a fixed buffer size set to 16 kB. This should be
enough for most use with three handles (that is how many we allow at the
moment). Parametrize the buffer size while doing this, so that it is easier
to revisit this later on if required.

Cc: stable@vger.kernel.org
Reported-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Fixes: 745b361e ("tpm: infrastructure for TPM spaces")
Reviewed-by: default avatarJerry Snitselaar <jsnitsel@redhat.com>
Tested-by: default avatarStefan Berger <stefanb@linux.ibm.com>
Signed-off-by: default avatarJarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
parent 7f3d176f

drivers/char/tpm/tpm-chip.c

+2 −7
Original line number Diff line number Diff line
@@ -386,13 +386,8 @@ struct tpm_chip *tpm_chip_alloc(struct device *pdev, 
	chip->cdev.owner = THIS_MODULE;

	chip->cdevs.owner = THIS_MODULE;



	chip->work_space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);

	if (!chip->work_space.context_buf) {

		rc = -ENOMEM;

		goto out;

	}

	chip->work_space.session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);

	if (!chip->work_space.session_buf) {

	rc = tpm2_init_space(&chip->work_space, TPM2_SPACE_BUFFER_SIZE);

	if (rc) {

		rc = -ENOMEM;

		goto out;

	}

drivers/char/tpm/tpm.h

+4 −1
Original line number Diff line number Diff line
@@ -59,6 +59,9 @@ enum tpm_addr { 


#define TPM_TAG_RQU_COMMAND 193



/* TPM2 specific constants. */

#define TPM2_SPACE_BUFFER_SIZE		16384 /* 16 kB */



struct	stclear_flags_t {

	__be16	tag;

	u8	deactivated;
@@ -228,7 +231,7 @@ unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); 
int tpm2_probe(struct tpm_chip *chip);

int tpm2_get_cc_attrs_tbl(struct tpm_chip *chip);

int tpm2_find_cc(struct tpm_chip *chip, u32 cc);

int tpm2_init_space(struct tpm_space *space);

int tpm2_init_space(struct tpm_space *space, unsigned int buf_size);

void tpm2_del_space(struct tpm_chip *chip, struct tpm_space *space);

void tpm2_flush_space(struct tpm_chip *chip);

int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd,

drivers/char/tpm/tpm2-space.c

+16 −10
Original line number Diff line number Diff line
@@ -38,18 +38,21 @@ static void tpm2_flush_sessions(struct tpm_chip *chip, struct tpm_space *space) 
	}

}



int tpm2_init_space(struct tpm_space *space)

int tpm2_init_space(struct tpm_space *space, unsigned int buf_size)

{

	space->context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);

	space->context_buf = kzalloc(buf_size, GFP_KERNEL);

	if (!space->context_buf)

		return -ENOMEM;



	space->session_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);

	space->session_buf = kzalloc(buf_size, GFP_KERNEL);

	if (space->session_buf == NULL) {

		kfree(space->context_buf);

		/* Prevent caller getting a dangling pointer. */

		space->context_buf = NULL;

		return -ENOMEM;

	}



	space->buf_size = buf_size;

	return 0;

}
@@ -311,8 +314,10 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u8 *cmd, 
	       sizeof(space->context_tbl));

	memcpy(&chip->work_space.session_tbl, &space->session_tbl,

	       sizeof(space->session_tbl));

	memcpy(chip->work_space.context_buf, space->context_buf, PAGE_SIZE);

	memcpy(chip->work_space.session_buf, space->session_buf, PAGE_SIZE);

	memcpy(chip->work_space.context_buf, space->context_buf,

	       space->buf_size);

	memcpy(chip->work_space.session_buf, space->session_buf,

	       space->buf_size);



	rc = tpm2_load_space(chip);

	if (rc) {
@@ -492,7 +497,7 @@ static int tpm2_save_space(struct tpm_chip *chip) 
			continue;



		rc = tpm2_save_context(chip, space->context_tbl[i],

				       space->context_buf, PAGE_SIZE,

				       space->context_buf, space->buf_size,

				       &offset);

		if (rc == -ENOENT) {

			space->context_tbl[i] = 0;
@@ -509,9 +514,8 @@ static int tpm2_save_space(struct tpm_chip *chip) 
			continue;



		rc = tpm2_save_context(chip, space->session_tbl[i],

				       space->session_buf, PAGE_SIZE,

				       space->session_buf, space->buf_size,

				       &offset);



		if (rc == -ENOENT) {

			/* handle error saving session, just forget it */

			space->session_tbl[i] = 0;
@@ -557,8 +561,10 @@ int tpm2_commit_space(struct tpm_chip *chip, struct tpm_space *space, 
	       sizeof(space->context_tbl));

	memcpy(&space->session_tbl, &chip->work_space.session_tbl,

	       sizeof(space->session_tbl));

	memcpy(space->context_buf, chip->work_space.context_buf, PAGE_SIZE);

	memcpy(space->session_buf, chip->work_space.session_buf, PAGE_SIZE);

	memcpy(space->context_buf, chip->work_space.context_buf,

	       space->buf_size);

	memcpy(space->session_buf, chip->work_space.session_buf,

	       space->buf_size);



	return 0;

out:

drivers/char/tpm/tpmrm-dev.c

+1 −1
Original line number Diff line number Diff line
@@ -21,7 +21,7 @@ static int tpmrm_open(struct inode *inode, struct file *file) 
	if (priv == NULL)

		return -ENOMEM;



	rc = tpm2_init_space(&priv->space);

	rc = tpm2_init_space(&priv->space, TPM2_SPACE_BUFFER_SIZE);

	if (rc) {

		kfree(priv);

		return -ENOMEM;

include/linux/tpm.h

+1 −0
Original line number Diff line number Diff line
@@ -96,6 +96,7 @@ struct tpm_space { 
	u8 *context_buf;

	u32 session_tbl[3];

	u8 *session_buf;

	u32 buf_size;

};



struct tpm_bios_log {

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