diff mbox

[tpmdd-devel,v4,2/8] tpm: replace dynamically allocated bios_dir with dentry array

Message ID 1475051682-23060-3-git-send-email-nayna@linux.vnet.ibm.com
State New
Headers show

Commit Message

Nayna Sept. 28, 2016, 8:34 a.m. UTC 
bios_dir is defined as struct dentry **bios_dir, which results in
dynamic allocation and therefore possibly a memory leak. This patch
replaces it with struct dentry array(struct dentry *bios_dir[3])
similar to what is done for sysfs groups.

Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
---
 drivers/char/tpm/tpm-chip.c     |  8 +++---
 drivers/char/tpm/tpm.h          |  3 +-
 drivers/char/tpm/tpm_eventlog.c | 63 +++++++++++++++++++----------------------
 drivers/char/tpm/tpm_eventlog.h | 10 +++----
 4 files changed, 40 insertions(+), 44 deletions(-)

Comments

Jarkko Sakkinen Sept. 30, 2016, 6:27 p.m. UTC | #1 
On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:
> bios_dir is defined as struct dentry **bios_dir, which results in
> dynamic allocation and therefore possibly a memory leak. This patch
> replaces it with struct dentry array(struct dentry *bios_dir[3])
> similar to what is done for sysfs groups.
> 
> Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> ---
>  drivers/char/tpm/tpm-chip.c     |  8 +++---
>  drivers/char/tpm/tpm.h          |  3 +-
>  drivers/char/tpm/tpm_eventlog.c | 63 +++++++++++++++++++----------------------
>  drivers/char/tpm/tpm_eventlog.h | 10 +++----
>  4 files changed, 40 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index e595013..826609d 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -278,14 +278,15 @@ static void tpm_del_char_device(struct tpm_chip *chip)
>  
>  static int tpm1_chip_register(struct tpm_chip *chip)
>  {
> +	int rc;
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
>  		return 0;
>  
>  	tpm_sysfs_add_device(chip);
>  
> -	chip->bios_dir = tpm_bios_log_setup(dev_name(&chip->dev));
> +	rc = tpm_bios_log_setup(chip);
>  
> -	return 0;
> +	return rc;
>  }
>  
>  static void tpm1_chip_unregister(struct tpm_chip *chip)
> @@ -293,8 +294,7 @@ static void tpm1_chip_unregister(struct tpm_chip *chip)
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
>  		return;
>  
> -	if (chip->bios_dir)
> -		tpm_bios_log_teardown(chip->bios_dir);
> +	tpm_bios_log_teardown(chip);
>  }
>  
>  static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 3e952fb..b5866bb 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -171,7 +171,8 @@ struct tpm_chip {
>  	unsigned long duration[3]; /* jiffies */
>  	bool duration_adjusted;
>  
> -	struct dentry **bios_dir;
> +	struct dentry *bios_dir[3];
> +	unsigned int bios_dir_count;

You should rather have a four entry array and use a NULL terminator.

>  	const struct attribute_group *groups[3];
>  	unsigned int groups_cnt;
> diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
> index 75e6644..f1df782 100644
> --- a/drivers/char/tpm/tpm_eventlog.c
> +++ b/drivers/char/tpm/tpm_eventlog.c
> @@ -332,7 +332,8 @@ static int tpm_bios_measurements_open(struct inode *inode,
>  	if (!log)
>  		return -ENOMEM;
>  
> -	if ((err = read_log(log)))
> +	err = read_log(log);
> +	if (err)
>  		goto out_free;
>  
>  	/* now register seq file */
> @@ -368,54 +369,48 @@ static int is_bad(void *p)
>  	return 0;
>  }
>  
> -struct dentry **tpm_bios_log_setup(const char *name)
> +int tpm_bios_log_setup(struct tpm_chip *chip)
>  {
> -	struct dentry **ret = NULL, *tpm_dir, *bin_file, *ascii_file;
> +	const char *name = dev_name(&chip->dev);
>  
> -	tpm_dir = securityfs_create_dir(name, NULL);
> -	if (is_bad(tpm_dir))
> -		goto out;
> +	chip->bios_dir_count = 0;
> +	chip->bios_dir[chip->bios_dir_count] =
> +		securityfs_create_dir(name, NULL);
> +	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
> +		goto err;
> +	chip->bios_dir_count++;
>  
> -	bin_file =
> +	chip->bios_dir[chip->bios_dir_count] =
>  	    securityfs_create_file("binary_bios_measurements",
> -				   S_IRUSR | S_IRGRP, tpm_dir,
> +				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
>  				   (void *)&tpm_binary_b_measurments_seqops,
>  				   &tpm_bios_measurements_ops);
> -	if (is_bad(bin_file))
> -		goto out_tpm;
> +	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
> +		goto err;
> +	chip->bios_dir_count++;
>  
> -	ascii_file =
> +	chip->bios_dir[chip->bios_dir_count] =
>  	    securityfs_create_file("ascii_bios_measurements",
> -				   S_IRUSR | S_IRGRP, tpm_dir,
> +				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
>  				   (void *)&tpm_ascii_b_measurments_seqops,
>  				   &tpm_bios_measurements_ops);
> -	if (is_bad(ascii_file))
> -		goto out_bin;
> +	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
> +		goto err;
> +	chip->bios_dir_count++;
>  
> -	ret = kmalloc(3 * sizeof(struct dentry *), GFP_KERNEL);
> -	if (!ret)
> -		goto out_ascii;
> -
> -	ret[0] = ascii_file;
> -	ret[1] = bin_file;
> -	ret[2] = tpm_dir;
> -
> -	return ret;
> +	return 0;
>  
> -out_ascii:
> -	securityfs_remove(ascii_file);
> -out_bin:
> -	securityfs_remove(bin_file);
> -out_tpm:
> -	securityfs_remove(tpm_dir);
> -out:
> -	return NULL;
> +err:
> +	tpm_bios_log_teardown(chip);
> +	return -EIO;
>  }
>  
> -void tpm_bios_log_teardown(struct dentry **lst)
> +void tpm_bios_log_teardown(struct tpm_chip *chip)
>  {
>  	int i;
>  
> -	for (i = 0; i < 3; i++)
> -		securityfs_remove(lst[i]);
> +	for (i = chip->bios_dir_count; i > 0; --i)
> +		securityfs_remove(chip->bios_dir[i-1]);
> +	chip->bios_dir_count = i;
> +
>  }
> diff --git a/drivers/char/tpm/tpm_eventlog.h b/drivers/char/tpm/tpm_eventlog.h
> index 8de62b0..fd3357e 100644
> --- a/drivers/char/tpm/tpm_eventlog.h
> +++ b/drivers/char/tpm/tpm_eventlog.h
> @@ -77,14 +77,14 @@ int read_log(struct tpm_bios_log *log);
>  
>  #if defined(CONFIG_TCG_IBMVTPM) || defined(CONFIG_TCG_IBMVTPM_MODULE) || \
>  	defined(CONFIG_ACPI)
> -extern struct dentry **tpm_bios_log_setup(const char *);
> -extern void tpm_bios_log_teardown(struct dentry **);
> +extern int tpm_bios_log_setup(struct tpm_chip *chip);
> +extern void tpm_bios_log_teardown(struct tpm_chip *chip);
>  #else
> -static inline struct dentry **tpm_bios_log_setup(const char *name)
> +static inline int tpm_bios_log_setup(struct tpm_chip *chip)
>  {
> -	return NULL;
> +	return 0;
>  }
> -static inline void tpm_bios_log_teardown(struct dentry **dir)
> +static inline void tpm_bios_log_teardown(struct tpm_chip *chip)
>  {
>  }
>  #endif
> -- 
> 2.5.0
> 

/Jarkko

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Jason Gunthorpe Sept. 30, 2016, 6:30 p.m. UTC | #2 
On Fri, Sep 30, 2016 at 09:27:03PM +0300, Jarkko Sakkinen wrote:
> On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:

> > -	struct dentry **bios_dir;
> > +	struct dentry *bios_dir[3];
> > +	unsigned int bios_dir_count;
> 
> You should rather have a four entry array and use a NULL terminator.

Why? Then everything has to compute the length before doing
anything. The basic ops are 'append to back' and 'pop off back' which
require length.

Jason

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Jarkko Sakkinen Sept. 30, 2016, 7:48 p.m. UTC | #3 
On Fri, Sep 30, 2016 at 12:30:26PM -0600, Jason Gunthorpe wrote:
> On Fri, Sep 30, 2016 at 09:27:03PM +0300, Jarkko Sakkinen wrote:
> > On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:
> 
> > > -	struct dentry **bios_dir;
> > > +	struct dentry *bios_dir[3];
> > > +	unsigned int bios_dir_count;
> > 
> > You should rather have a four entry array and use a NULL terminator.
> 
> Why? Then everything has to compute the length before doing
> anything. The basic ops are 'append to back' and 'pop off back' which
> require length.

One variable less to struct tpm_chip. The loop that removes the files
simply can continue until NULL is encountered.

Where do you need the length?

> Jason

/Jarkko

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Jason Gunthorpe Sept. 30, 2016, 8:31 p.m. UTC | #4 
On Fri, Sep 30, 2016 at 10:48:25PM +0300, Jarkko Sakkinen wrote:
> On Fri, Sep 30, 2016 at 12:30:26PM -0600, Jason Gunthorpe wrote:
> > On Fri, Sep 30, 2016 at 09:27:03PM +0300, Jarkko Sakkinen wrote:
> > > On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:
> > 
> > > > -	struct dentry **bios_dir;
> > > > +	struct dentry *bios_dir[3];
> > > > +	unsigned int bios_dir_count;
> > > 
> > > You should rather have a four entry array and use a NULL terminator.
> > 
> > Why? Then everything has to compute the length before doing
> > anything. The basic ops are 'append to back' and 'pop off back' which
> > require length.
> 
> One variable less to struct tpm_chip. The loop that removes the files
> simply can continue until NULL is encountered.

We've been over this, the loop has to remove them in reverse over.

Why are you so concerned about size of tpm_chip??

> Where do you need the length?

Every place that touches the array

Jason

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Jarkko Sakkinen Oct. 1, 2016, 12:06 p.m. UTC | #5 
On Fri, Sep 30, 2016 at 02:31:47PM -0600, Jason Gunthorpe wrote:
> On Fri, Sep 30, 2016 at 10:48:25PM +0300, Jarkko Sakkinen wrote:
> > On Fri, Sep 30, 2016 at 12:30:26PM -0600, Jason Gunthorpe wrote:
> > > On Fri, Sep 30, 2016 at 09:27:03PM +0300, Jarkko Sakkinen wrote:
> > > > On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:
> > > 
> > > > > -	struct dentry **bios_dir;
> > > > > +	struct dentry *bios_dir[3];
> > > > > +	unsigned int bios_dir_count;
> > > > 
> > > > You should rather have a four entry array and use a NULL terminator.
> > > 
> > > Why? Then everything has to compute the length before doing
> > > anything. The basic ops are 'append to back' and 'pop off back' which
> > > require length.
> > 
> > One variable less to struct tpm_chip. The loop that removes the files
> > simply can continue until NULL is encountered.
> 
> We've been over this, the loop has to remove them in reverse over.
> 
> Why are you so concerned about size of tpm_chip??

It's not the size. It's the added complexity.

I'll look into revising this commit a bit in order in order to move
things forward...

/Jarkko

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Jarkko Sakkinen Oct. 1, 2016, 12:27 p.m. UTC | #6 
On Wed, Sep 28, 2016 at 04:34:36AM -0400, Nayna Jain wrote:
> bios_dir is defined as struct dentry **bios_dir, which results in
> dynamic allocation and therefore possibly a memory leak. This patch
> replaces it with struct dentry array(struct dentry *bios_dir[3])
> similar to what is done for sysfs groups.
> 
> Suggested-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> Signed-off-by: Nayna Jain <nayna@linux.vnet.ibm.com>
> Reviewed-by: Jason Gunthorpe <jgunthorpe@obsidianresearch.com>
> ---
>  drivers/char/tpm/tpm-chip.c     |  8 +++---
>  drivers/char/tpm/tpm.h          |  3 +-
>  drivers/char/tpm/tpm_eventlog.c | 63 +++++++++++++++++++----------------------
>  drivers/char/tpm/tpm_eventlog.h | 10 +++----
>  4 files changed, 40 insertions(+), 44 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index e595013..826609d 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -278,14 +278,15 @@ static void tpm_del_char_device(struct tpm_chip *chip)
>  
>  static int tpm1_chip_register(struct tpm_chip *chip)
>  {
> +	int rc;
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
>  		return 0;
>  
>  	tpm_sysfs_add_device(chip);
>  
> -	chip->bios_dir = tpm_bios_log_setup(dev_name(&chip->dev));
> +	rc = tpm_bios_log_setup(chip);
>  
> -	return 0;
> +	return rc;
>  }
>  
>  static void tpm1_chip_unregister(struct tpm_chip *chip)
> @@ -293,8 +294,7 @@ static void tpm1_chip_unregister(struct tpm_chip *chip)
>  	if (chip->flags & TPM_CHIP_FLAG_TPM2)
>  		return;
>  
> -	if (chip->bios_dir)
> -		tpm_bios_log_teardown(chip->bios_dir);
> +	tpm_bios_log_teardown(chip);
>  }
>  
>  static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
> diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
> index 3e952fb..b5866bb 100644
> --- a/drivers/char/tpm/tpm.h
> +++ b/drivers/char/tpm/tpm.h
> @@ -171,7 +171,8 @@ struct tpm_chip {
>  	unsigned long duration[3]; /* jiffies */
>  	bool duration_adjusted;
>  
> -	struct dentry **bios_dir;
> +	struct dentry *bios_dir[3];
> +	unsigned int bios_dir_count;
>  
>  	const struct attribute_group *groups[3];
>  	unsigned int groups_cnt;
> diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
> index 75e6644..f1df782 100644
> --- a/drivers/char/tpm/tpm_eventlog.c
> +++ b/drivers/char/tpm/tpm_eventlog.c
> @@ -332,7 +332,8 @@ static int tpm_bios_measurements_open(struct inode *inode,
>  	if (!log)
>  		return -ENOMEM;
>  
> -	if ((err = read_log(log)))
> +	err = read_log(log);
> +	if (err)
>  		goto out_free;
>  
>  	/* now register seq file */
> @@ -368,54 +369,48 @@ static int is_bad(void *p)
>  	return 0;
>  }
>  
> -struct dentry **tpm_bios_log_setup(const char *name)
> +int tpm_bios_log_setup(struct tpm_chip *chip)
>  {
> -	struct dentry **ret = NULL, *tpm_dir, *bin_file, *ascii_file;
> +	const char *name = dev_name(&chip->dev);
>  
> -	tpm_dir = securityfs_create_dir(name, NULL);
> -	if (is_bad(tpm_dir))
> -		goto out;
> +	chip->bios_dir_count = 0;
> +	chip->bios_dir[chip->bios_dir_count] =
> +		securityfs_create_dir(name, NULL);
> +	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
> +		goto err;
> +	chip->bios_dir_count++;
>  
> -	bin_file =
> +	chip->bios_dir[chip->bios_dir_count] =
>  	    securityfs_create_file("binary_bios_measurements",
> -				   S_IRUSR | S_IRGRP, tpm_dir,
> +				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
>  				   (void *)&tpm_binary_b_measurments_seqops,
>  				   &tpm_bios_measurements_ops);
> -	if (is_bad(bin_file))
> -		goto out_tpm;
> +	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
> +		goto err;
> +	chip->bios_dir_count++;
>  
> -	ascii_file =
> +	chip->bios_dir[chip->bios_dir_count] =
>  	    securityfs_create_file("ascii_bios_measurements",
> -				   S_IRUSR | S_IRGRP, tpm_dir,
> +				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
>  				   (void *)&tpm_ascii_b_measurments_seqops,
>  				   &tpm_bios_measurements_ops);

The following securityfs_create_file calls overwrite the same field,
which leaks memory, as you pass chip->biod_dir[0] to these calls.

I guess securityfs_remove() returns with NULL input (haven't checked).

/Jarkko

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diff mbox

Patch

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index e595013..826609d 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -278,14 +278,15 @@  static void tpm_del_char_device(struct tpm_chip *chip)
 
 static int tpm1_chip_register(struct tpm_chip *chip)
 {
+	int rc;
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		return 0;
 
 	tpm_sysfs_add_device(chip);
 
-	chip->bios_dir = tpm_bios_log_setup(dev_name(&chip->dev));
+	rc = tpm_bios_log_setup(chip);
 
-	return 0;
+	return rc;
 }
 
 static void tpm1_chip_unregister(struct tpm_chip *chip)
@@ -293,8 +294,7 @@  static void tpm1_chip_unregister(struct tpm_chip *chip)
 	if (chip->flags & TPM_CHIP_FLAG_TPM2)
 		return;
 
-	if (chip->bios_dir)
-		tpm_bios_log_teardown(chip->bios_dir);
+	tpm_bios_log_teardown(chip);
 }
 
 static void tpm_del_legacy_sysfs(struct tpm_chip *chip)
diff --git a/drivers/char/tpm/tpm.h b/drivers/char/tpm/tpm.h
index 3e952fb..b5866bb 100644
--- a/drivers/char/tpm/tpm.h
+++ b/drivers/char/tpm/tpm.h
@@ -171,7 +171,8 @@  struct tpm_chip {
 	unsigned long duration[3]; /* jiffies */
 	bool duration_adjusted;
 
-	struct dentry **bios_dir;
+	struct dentry *bios_dir[3];
+	unsigned int bios_dir_count;
 
 	const struct attribute_group *groups[3];
 	unsigned int groups_cnt;
diff --git a/drivers/char/tpm/tpm_eventlog.c b/drivers/char/tpm/tpm_eventlog.c
index 75e6644..f1df782 100644
--- a/drivers/char/tpm/tpm_eventlog.c
+++ b/drivers/char/tpm/tpm_eventlog.c
@@ -332,7 +332,8 @@  static int tpm_bios_measurements_open(struct inode *inode,
 	if (!log)
 		return -ENOMEM;
 
-	if ((err = read_log(log)))
+	err = read_log(log);
+	if (err)
 		goto out_free;
 
 	/* now register seq file */
@@ -368,54 +369,48 @@  static int is_bad(void *p)
 	return 0;
 }
 
-struct dentry **tpm_bios_log_setup(const char *name)
+int tpm_bios_log_setup(struct tpm_chip *chip)
 {
-	struct dentry **ret = NULL, *tpm_dir, *bin_file, *ascii_file;
+	const char *name = dev_name(&chip->dev);
 
-	tpm_dir = securityfs_create_dir(name, NULL);
-	if (is_bad(tpm_dir))
-		goto out;
+	chip->bios_dir_count = 0;
+	chip->bios_dir[chip->bios_dir_count] =
+		securityfs_create_dir(name, NULL);
+	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
+		goto err;
+	chip->bios_dir_count++;
 
-	bin_file =
+	chip->bios_dir[chip->bios_dir_count] =
 	    securityfs_create_file("binary_bios_measurements",
-				   S_IRUSR | S_IRGRP, tpm_dir,
+				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
 				   (void *)&tpm_binary_b_measurments_seqops,
 				   &tpm_bios_measurements_ops);
-	if (is_bad(bin_file))
-		goto out_tpm;
+	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
+		goto err;
+	chip->bios_dir_count++;
 
-	ascii_file =
+	chip->bios_dir[chip->bios_dir_count] =
 	    securityfs_create_file("ascii_bios_measurements",
-				   S_IRUSR | S_IRGRP, tpm_dir,
+				   S_IRUSR | S_IRGRP, chip->bios_dir[0],
 				   (void *)&tpm_ascii_b_measurments_seqops,
 				   &tpm_bios_measurements_ops);
-	if (is_bad(ascii_file))
-		goto out_bin;
+	if (is_bad(chip->bios_dir[chip->bios_dir_count]))
+		goto err;
+	chip->bios_dir_count++;
 
-	ret = kmalloc(3 * sizeof(struct dentry *), GFP_KERNEL);
-	if (!ret)
-		goto out_ascii;
-
-	ret[0] = ascii_file;
-	ret[1] = bin_file;
-	ret[2] = tpm_dir;
-
-	return ret;
+	return 0;
 
-out_ascii:
-	securityfs_remove(ascii_file);
-out_bin:
-	securityfs_remove(bin_file);
-out_tpm:
-	securityfs_remove(tpm_dir);
-out:
-	return NULL;
+err:
+	tpm_bios_log_teardown(chip);
+	return -EIO;
 }
 
-void tpm_bios_log_teardown(struct dentry **lst)
+void tpm_bios_log_teardown(struct tpm_chip *chip)
 {
 	int i;
 
-	for (i = 0; i < 3; i++)
-		securityfs_remove(lst[i]);
+	for (i = chip->bios_dir_count; i > 0; --i)
+		securityfs_remove(chip->bios_dir[i-1]);
+	chip->bios_dir_count = i;
+
 }
diff --git a/drivers/char/tpm/tpm_eventlog.h b/drivers/char/tpm/tpm_eventlog.h
index 8de62b0..fd3357e 100644
--- a/drivers/char/tpm/tpm_eventlog.h
+++ b/drivers/char/tpm/tpm_eventlog.h
@@ -77,14 +77,14 @@  int read_log(struct tpm_bios_log *log);
 
 #if defined(CONFIG_TCG_IBMVTPM) || defined(CONFIG_TCG_IBMVTPM_MODULE) || \
 	defined(CONFIG_ACPI)
-extern struct dentry **tpm_bios_log_setup(const char *);
-extern void tpm_bios_log_teardown(struct dentry **);
+extern int tpm_bios_log_setup(struct tpm_chip *chip);
+extern void tpm_bios_log_teardown(struct tpm_chip *chip);
 #else
-static inline struct dentry **tpm_bios_log_setup(const char *name)
+static inline int tpm_bios_log_setup(struct tpm_chip *chip)
 {
-	return NULL;
+	return 0;
 }
-static inline void tpm_bios_log_teardown(struct dentry **dir)
+static inline void tpm_bios_log_teardown(struct tpm_chip *chip)
 {
 }
 #endif