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Commit 2960f9a5 authored by Brijesh Singh's avatar Brijesh Singh
Browse files

crypto: ccp: Implement SEV_FACTORY_RESET ioctl command 



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 <pbonzini@redhat.com>
Cc: "Radim Krčmář" <rkrcmar@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Gary Hook <gary.hook@amd.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: linux-crypto@vger.kernel.org
Cc: kvm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Improvements-by: default avatarBorislav Petkov <bp@suse.de>
Signed-off-by: default avatarBrijesh Singh <brijesh.singh@amd.com>
parent 200664d5

drivers/crypto/ccp/psp-dev.c

+76 −1
Original line number Diff line number Diff line
@@ -232,9 +232,84 @@ static int sev_platform_shutdown(int *error) 
	return rc;

}



static int sev_get_platform_state(int *state, int *error)

{

	int rc;



	rc = __sev_do_cmd_locked(SEV_CMD_PLATFORM_STATUS,

				 &psp_master->status_cmd_buf, error);

	if (rc)

		return rc;



	*state = psp_master->status_cmd_buf.state;

	return rc;

}



static int sev_ioctl_do_reset(struct sev_issue_cmd *argp)

{

	int state, rc;



	/*

	 * The SEV spec requires that FACTORY_RESET must be issued in

	 * UNINIT state. Before we go further lets check if any guest is

	 * active.

	 *

	 * If FW is in WORKING state then deny the request otherwise issue

	 * SHUTDOWN command do INIT -> UNINIT before issuing the FACTORY_RESET.

	 *

	 */

	rc = sev_get_platform_state(&state, &argp->error);

	if (rc)

		return rc;



	if (state == SEV_STATE_WORKING)

		return -EBUSY;



	if (state == SEV_STATE_INIT) {

		rc = __sev_platform_shutdown_locked(&argp->error);

		if (rc)

			return rc;

	}



	return __sev_do_cmd_locked(SEV_CMD_FACTORY_RESET, 0, &argp->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(&input, argp, sizeof(struct sev_issue_cmd)))

		return -EFAULT;



	if (input.cmd > SEV_MAX)

		return -EINVAL;



	mutex_lock(&sev_cmd_mutex);



	switch (input.cmd) {



	case SEV_FACTORY_RESET:

		ret = sev_ioctl_do_reset(&input);

		break;

	default:

		ret = -EINVAL;

		goto out;

	}



	if (copy_to_user(argp, &input, sizeof(struct sev_issue_cmd)))

		ret = -EFAULT;

out:

	mutex_unlock(&sev_cmd_mutex);



	return ret;

}



static const struct file_operations sev_fops = {