On Wed, Jan 04, 2017 at 12:50:21PM -0500, Stefan Berger wrote:
> Jarkko Sakkinen <jarkko.sakki...@linux.intel.com> wrote on 01/02/2017
> 08:22:10 AM:
>
> >
> > Added a ioctl for creating a TPM space. The space is isolated from the
> > other users of the TPM. Only a process holding the file with the handle
> > can access the objects and only objects that are created through that
> > file handle can be accessed.
> >
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakki...@linux.intel.com>
> > ---
>
> > diff --git a/drivers/char/tpm/tpm-dev.c b/drivers/char/tpm/tpm-dev.c
> > index 912ad30..139638b 100644
> > --- a/drivers/char/tpm/tpm-dev.c
> > +++ b/drivers/char/tpm/tpm-dev.c
> > @@ -19,6 +19,7 @@
> > */
> > #include <linux/slab.h>
> > #include <linux/uaccess.h>
> > +#include <uapi/linux/tpm.h>
> > #include "tpm.h"
> >
> > struct file_priv {
> > @@ -32,6 +33,8 @@ struct file_priv {
> > struct work_struct work;
> >
> > u8 data_buffer[TPM_BUFSIZE];
> > + struct tpm_space space;
> > + bool has_space;
> > };
> >
> > static void user_reader_timeout(unsigned long ptr)
> > @@ -115,6 +118,7 @@ static ssize_t tpm_write(struct file *file,
> > const char __user *buf,
> > size_t size, loff_t *off)
> > {
> > struct file_priv *priv = file->private_data;
> > + struct tpm_space *space = NULL;
> > size_t in_size = size;
> > ssize_t out_size;
> >
> > @@ -130,6 +134,9 @@ static ssize_t tpm_write(struct file *file,
> > const char __user *buf,
> >
> > mutex_lock(&priv->buffer_mutex);
> >
> > + if (priv->has_space)
> > + space = &priv->space;
> > +
> > if (copy_from_user
> > (priv->data_buffer, (void __user *) buf, in_size)) {
> > mutex_unlock(&priv->buffer_mutex);
> > @@ -144,7 +151,7 @@ static ssize_t tpm_write(struct file *file,
> > const char __user *buf,
> > mutex_unlock(&priv->buffer_mutex);
> > return -EPIPE;
> > }
> > - out_size = tpm_transmit(priv->chip, priv->data_buffer,
> > + out_size = tpm_transmit(priv->chip, space, priv->data_buffer,
> > sizeof(priv->data_buffer), 0);
> >
> > tpm_put_ops(priv->chip);
> > @@ -162,6 +169,65 @@ static ssize_t tpm_write(struct file *file,
> > const char __user *buf,
> > return in_size;
> > }
> >
> > +/**
> > + * tpm_ioc_new_space - handler for %SGX_IOC_NEW_SPACE ioctl
> > + *
> > + * Creates a new TPM space that can hold a set of transient
> > objects. The space
> > + * is isolated with virtual handles that are mapped into physical
> > handles by the
> > + * driver.
> > + */
> > +static long tpm_ioc_new_space(struct file *file, unsigned int ioctl,
> > + unsigned long arg)
> > +{
> > + struct file_priv *priv = file->private_data;
> > + struct tpm_chip *chip = priv->chip;
> > + int rc = 0;
> > +
> > + if (!(chip->flags & TPM_CHIP_FLAG_TPM2))
> > + return -EOPNOTSUPP;
> > +
> > + mutex_lock(&priv->buffer_mutex);
> > +
> > + if (priv->has_space) {
> > + rc = -EBUSY;
> > + goto out;
> > + }
> > +
> > + priv->space.context_buf = kzalloc(PAGE_SIZE, GFP_KERNEL);
> > + if (!priv->space.context_buf) {
> > + rc = -ENOMEM;
> > + goto out;
> > + }
> > +
> > + /* The TPM device can be opened again as this file has been moved to
> a
> > + * TPM handle space.
> > + */
> > + priv->has_space = true;
> > + clear_bit(0, &chip->is_open);
> > +out:
> > + mutex_unlock(&priv->buffer_mutex);
> > + return rc;
> > +}
> > +
> > +static long tpm_ioctl(struct file *file, unsigned int ioctl,
> > + unsigned long arg)
> > +{
> > + switch (ioctl) {
> > + case TPM_IOC_NEW_SPACE:
> > + return tpm_ioc_new_space(file, ioctl, arg);
> > + default:
> > + return -ENOIOCTLCMD;
> > + }
> > +}
> > +
> > +#ifdef CONFIG_COMPAT
> > +static long tpm_compat_ioctl(struct file *file, unsigned int ioctl,
> > + unsigned long arg)
> > +{
> > + return tpm_ioctl(file, ioctl, arg);
> > +}
> > +#endif
> > +
> > /*
> > * Called on file close
> > */
> > @@ -169,6 +235,14 @@ static int tpm_release(struct inode *inode,
> > struct file *file)
> > {
> > struct file_priv *priv = file->private_data;
> >
> > + if (tpm_try_get_ops(priv->chip)) {
> > + mutex_unlock(&priv->buffer_mutex);
> > + return -EPIPE;
> > + }
>
> That mutex_unlock looks wrong.
Thanks.
This will be anyway gone with own device file.
> Stefan
/Jarkko
