From: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com
[ Upstream commit 6c4e79d99e6f42b79040f1a33cd4018f5425030b ]
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: Stefan Berger stefanb@linux.ibm.com Fixes: 745b361e989a ("tpm: infrastructure for TPM spaces") Reviewed-by: Jerry Snitselaar jsnitsel@redhat.com Tested-by: Stefan Berger stefanb@linux.ibm.com Signed-off-by: Jarkko Sakkinen jarkko.sakkinen@linux.intel.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/char/tpm/tpm-chip.c | 9 ++------- drivers/char/tpm/tpm.h | 6 +++++- drivers/char/tpm/tpm2-space.c | 26 ++++++++++++++++---------- drivers/char/tpm/tpmrm-dev.c | 2 +- 4 files changed, 24 insertions(+), 19 deletions(-)
diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index f3ae8a32d1d5..8280fcd5130e 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -274,13 +274,8 @@ 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; } diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h index 289221d653cb..b9a30f0b8825 100644 --- a/drivers/char/tpm/tpm.h +++ b/drivers/char/tpm/tpm.h @@ -188,6 +188,7 @@ struct tpm_space { u8 *context_buf; u32 session_tbl[3]; u8 *session_buf; + u32 buf_size; };
enum tpm_chip_flags { @@ -278,6 +279,9 @@ struct tpm_output_header {
#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; @@ -595,7 +599,7 @@ void tpm2_shutdown(struct tpm_chip *chip, u16 shutdown_type); unsigned long tpm2_calc_ordinal_duration(struct tpm_chip *chip, u32 ordinal); int tpm2_probe(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); int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc, u8 *cmd); diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c index d2e101b32482..9f4e22dcde27 100644 --- a/drivers/char/tpm/tpm2-space.c +++ b/drivers/char/tpm/tpm2-space.c @@ -43,18 +43,21 @@ 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; }
@@ -276,8 +279,10 @@ int tpm2_prepare_space(struct tpm_chip *chip, struct tpm_space *space, u32 cc, 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) { @@ -456,7 +461,7 @@ 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; @@ -474,9 +479,8 @@ 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; @@ -522,8 +526,10 @@ 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; } diff --git a/drivers/char/tpm/tpmrm-dev.c b/drivers/char/tpm/tpmrm-dev.c index 1a0e97a5da5a..162fb16243d0 100644 --- a/drivers/char/tpm/tpmrm-dev.c +++ b/drivers/char/tpm/tpmrm-dev.c @@ -22,7 +22,7 @@ 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;