Re: [Part2 PATCH v7 14/38] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command

[Borislav Petkov]

On Wed, Nov 01, 2017 at 04:15:59PM -0500, Brijesh Singh wrote:
> The SEV_FACTORY_RESET command can be used by the platform owner to
> reset the non-volatile SEV related data. The command is defined in
> SEV spec section 5.4
> 
> Cc: Paolo Bonzini 
> Cc: "Radim Krčmář" 
> Cc: Borislav Petkov 
> Cc: Herbert Xu 
> Cc: Gary Hook 
> Cc: Tom Lendacky 
> Cc: linux-cry...@vger.kernel.org
> Cc: k...@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Improvements-by: Borislav Petkov 
> Signed-off-by: Brijesh Singh 
> Acked-by: Gary R Hook 

Acked-by: needs to go away too if you send a new revision with
non-trivial changes. Same as with Reviewed-by: tags.

> ---
>  drivers/crypto/ccp/psp-dev.c | 70 
> +++-
>  1 file changed, 69 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
> index c61ca16096ca..a757bd1c34e8 100644
> --- a/drivers/crypto/ccp/psp-dev.c
> +++ b/drivers/crypto/ccp/psp-dev.c
> @@ -235,9 +235,77 @@ static int sev_platform_shutdown(int *error)
>   return rc;
>  }
>  
> +static int sev_platform_state(int *state, int *error)

It needs a verb in the name: sev_get_platform_state()

> +{
> + int rc;
> +
> + rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
> +  psp_master->sev_status, error);
> + if (rc)
> + return rc;
> +
> + *state = psp_master->sev_status->state;
> + return rc;
> +}
> +
> +static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
> +{
> + int state, rc;
> +
> + rc = sev_platform_state(, >error);
> + if (rc)
> + return rc;
> +
> + if (state == SEV_STATE_WORKING) {

You could write a short blurb somewhere in a comment around here, what
the logic now is going to be for the SEV device: If in working state,
reset is denied. All other states accept it, because... .

> + argp->error = SEV_RET_INVALID_PLATFORM_STATE;

If you're going to write enum psp_ret_code types into argp->error, then
it needs to be of enum psp_ret_code type and not an int.

> + return -EBUSY;
> + }
> +
> + if (state == SEV_STATE_INIT) {
> + rc = __sev_platform_shutdown_locked(>error);
> + if (rc)
> + return rc;
> + }
> +
> + return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, >error);
> +}

-- 
Regards/Gruss,
Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

Re: [Part2 PATCH v7 14/38] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command

[Borislav Petkov]

On Wed, Nov 01, 2017 at 04:15:59PM -0500, Brijesh Singh wrote:
> The SEV_FACTORY_RESET command can be used by the platform owner to
> reset the non-volatile SEV related data. The command is defined in
> SEV spec section 5.4
> 
> Cc: Paolo Bonzini 
> Cc: "Radim Krčmář" 
> Cc: Borislav Petkov 
> Cc: Herbert Xu 
> Cc: Gary Hook 
> Cc: Tom Lendacky 
> Cc: linux-cry...@vger.kernel.org
> Cc: k...@vger.kernel.org
> Cc: linux-kernel@vger.kernel.org
> Improvements-by: Borislav Petkov 
> Signed-off-by: Brijesh Singh 
> Acked-by: Gary R Hook 

Acked-by: needs to go away too if you send a new revision with
non-trivial changes. Same as with Reviewed-by: tags.

> ---
>  drivers/crypto/ccp/psp-dev.c | 70 
> +++-
>  1 file changed, 69 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
> index c61ca16096ca..a757bd1c34e8 100644
> --- a/drivers/crypto/ccp/psp-dev.c
> +++ b/drivers/crypto/ccp/psp-dev.c
> @@ -235,9 +235,77 @@ static int sev_platform_shutdown(int *error)
>   return rc;
>  }
>  
> +static int sev_platform_state(int *state, int *error)

It needs a verb in the name: sev_get_platform_state()

> +{
> + int rc;
> +
> + rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
> +  psp_master->sev_status, error);
> + if (rc)
> + return rc;
> +
> + *state = psp_master->sev_status->state;
> + return rc;
> +}
> +
> +static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
> +{
> + int state, rc;
> +
> + rc = sev_platform_state(, >error);
> + if (rc)
> + return rc;
> +
> + if (state == SEV_STATE_WORKING) {

You could write a short blurb somewhere in a comment around here, what
the logic now is going to be for the SEV device: If in working state,
reset is denied. All other states accept it, because... .

> + argp->error = SEV_RET_INVALID_PLATFORM_STATE;

If you're going to write enum psp_ret_code types into argp->error, then
it needs to be of enum psp_ret_code type and not an int.

> + return -EBUSY;
> + }
> +
> + if (state == SEV_STATE_INIT) {
> + rc = __sev_platform_shutdown_locked(>error);
> + if (rc)
> + return rc;
> + }
> +
> + return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, >error);
> +}

-- 
Regards/Gruss,
Boris.

Good mailing practices for 400: avoid top-posting and trim the reply.

[Part2 PATCH v7 14/38] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command

[Brijesh Singh]

The SEV_FACTORY_RESET command can be used by the platform owner to
reset the non-volatile SEV related data. The command is defined in
SEV spec section 5.4

Cc: Paolo Bonzini 
Cc: "Radim Krčmář" 
Cc: Borislav Petkov 
Cc: Herbert Xu 
Cc: Gary Hook 
Cc: Tom Lendacky 
Cc: linux-cry...@vger.kernel.org
Cc: k...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov 
Signed-off-by: Brijesh Singh 
Acked-by: Gary R Hook 
---
 drivers/crypto/ccp/psp-dev.c | 70 +++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index c61ca16096ca..a757bd1c34e8 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -235,9 +235,77 @@ static int sev_platform_shutdown(int *error)
return rc;
 }
 
+static int sev_platform_state(int *state, int *error)
+{
+   int rc;
+
+   rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
+psp_master->sev_status, error);
+   if (rc)
+   return rc;
+
+   *state = psp_master->sev_status->state;
+   return rc;
+}
+
+static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
+{
+   int state, rc;
+
+   rc = sev_platform_state(, >error);
+   if (rc)
+   return rc;
+
+   if (state == SEV_STATE_WORKING) {
+   argp->error = SEV_RET_INVALID_PLATFORM_STATE;
+   return -EBUSY;
+   }
+
+   if (state == SEV_STATE_INIT) {
+   rc = __sev_platform_shutdown_locked(>error);
+   if (rc)
+   return rc;
+   }
+
+   return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, >error);
+}
+
 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
 {
-   return -ENOTTY;
+   void __user *argp = (void __user *)arg;
+   struct sev_issue_cmd input;
+   int ret = -EFAULT;
+
+   if (!psp_master)
+   return -ENODEV;
+
+   if (ioctl != SEV_ISSUE_CMD)
+   return -EINVAL;
+
+   if (copy_from_user(, argp, sizeof(struct sev_issue_cmd)))
+   return -EFAULT;
+
+   if (input.cmd > SEV_MAX)
+   return -EINVAL;
+
+   mutex_lock(_cmd_mutex);
+
+   switch (input.cmd) {
+
+   case SEV_FACTORY_RESET:
+   ret = sev_ioctl_do_reset();
+   break;
+   default:
+   ret = -EINVAL;
+   goto out;
+   }
+
+   if (copy_to_user(argp, , sizeof(struct sev_issue_cmd)))
+   ret = -EFAULT;
+out:
+   mutex_unlock(_cmd_mutex);
+
+   return ret;
 }
 
 static const struct file_operations sev_fops = {
-- 
2.9.5

[Part2 PATCH v7 14/38] crypto: ccp: Implement SEV_FACTORY_RESET ioctl command

[Brijesh Singh]

The SEV_FACTORY_RESET command can be used by the platform owner to
reset the non-volatile SEV related data. The command is defined in
SEV spec section 5.4

Cc: Paolo Bonzini 
Cc: "Radim Krčmář" 
Cc: Borislav Petkov 
Cc: Herbert Xu 
Cc: Gary Hook 
Cc: Tom Lendacky 
Cc: linux-cry...@vger.kernel.org
Cc: k...@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: Borislav Petkov 
Signed-off-by: Brijesh Singh 
Acked-by: Gary R Hook 
---
 drivers/crypto/ccp/psp-dev.c | 70 +++-
 1 file changed, 69 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/ccp/psp-dev.c b/drivers/crypto/ccp/psp-dev.c
index c61ca16096ca..a757bd1c34e8 100644
--- a/drivers/crypto/ccp/psp-dev.c
+++ b/drivers/crypto/ccp/psp-dev.c
@@ -235,9 +235,77 @@ static int sev_platform_shutdown(int *error)
return rc;
 }
 
+static int sev_platform_state(int *state, int *error)
+{
+   int rc;
+
+   rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,
+psp_master->sev_status, error);
+   if (rc)
+   return rc;
+
+   *state = psp_master->sev_status->state;
+   return rc;
+}
+
+static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)
+{
+   int state, rc;
+
+   rc = sev_platform_state(, >error);
+   if (rc)
+   return rc;
+
+   if (state == SEV_STATE_WORKING) {
+   argp->error = SEV_RET_INVALID_PLATFORM_STATE;
+   return -EBUSY;
+   }
+
+   if (state == SEV_STATE_INIT) {
+   rc = __sev_platform_shutdown_locked(>error);
+   if (rc)
+   return rc;
+   }
+
+   return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, >error);
+}
+
 static long sev_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
 {
-   return -ENOTTY;
+   void __user *argp = (void __user *)arg;
+   struct sev_issue_cmd input;
+   int ret = -EFAULT;
+
+   if (!psp_master)
+   return -ENODEV;
+
+   if (ioctl != SEV_ISSUE_CMD)
+   return -EINVAL;
+
+   if (copy_from_user(, argp, sizeof(struct sev_issue_cmd)))
+   return -EFAULT;
+
+   if (input.cmd > SEV_MAX)
+   return -EINVAL;
+
+   mutex_lock(_cmd_mutex);
+
+   switch (input.cmd) {
+
+   case SEV_FACTORY_RESET:
+   ret = sev_ioctl_do_reset();
+   break;
+   default:
+   ret = -EINVAL;
+   goto out;
+   }
+
+   if (copy_to_user(argp, , sizeof(struct sev_issue_cmd)))
+   ret = -EFAULT;
+out:
+   mutex_unlock(_cmd_mutex);
+
+   return ret;
 }
 
 static const struct file_operations sev_fops = {
-- 
2.9.5