Commit b7a88d85 authored by Shengjie Li's avatar Shengjie Li
Browse files

Fix token error issue when concurrent calls 

virtcca inclusion
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/IA6GOR



--------------------------------

Fix token error issue when concurrent calls

Fixes: 31071f4b ("cvm_tsi: add cvm tsi interface")
Signed-off-by: default avatarShengjie Li <lishengjie12@huawei.com>
parent 7501d447

arch/arm64/include/uapi/asm/cvm_tsi.h

+4 −2
Original line number Diff line number Diff line
@@ -23,9 +23,10 @@ 
 * This macro needs to be updated accordingly if new algorithms are supported.

 */

#define MAX_MEASUREMENT_SIZE       SHA512_SIZE

#define MAX_DEV_CERT_SIZE          4096

#define MAX_DEV_CERT_SIZE          (4096U)



#define MAX_TOKEN_GRANULE_PAGE     (10U)

#define GRANULE_SIZE               (4096U)

#define MAX_TOKEN_GRANULE_COUNT    (2U)

#define CHALLENGE_SIZE             (64U)



struct cvm_attester {
@@ -55,6 +56,7 @@ struct cvm_measurement_extend { 


struct cvm_attestation_cmd {

	unsigned char challenge[CHALLENGE_SIZE]; /* input: challenge value */

	unsigned char token[GRANULE_SIZE * MAX_TOKEN_GRANULE_COUNT];

	unsigned long token_size; /* return: token size */

};

arch/arm64/kernel/cvm_tsi.c

+20 −46
Original line number Diff line number Diff line
@@ -8,8 +8,6 @@ 
#include <asm/cvm_smc.h>

#include <asm/cvm_tsi.h>



#define GRANULE_SIZE PAGE_SIZE



struct attestation_token {

	void *buf;

	unsigned long size;
@@ -20,8 +18,6 @@ static struct attestation_token token; 
static DEFINE_MUTEX(token_lock);



static long tmm_tsi_ioctl(struct file *file, unsigned int cmd, unsigned long arg);

static ssize_t tmm_token_read(struct file *file, char __user *user_buffer,

	size_t size, loff_t *offset);



static int tmm_get_tsi_version(struct cvm_tsi_version __user *arg);

static int tmm_get_attestation_token(struct cvm_attestation_cmd __user *arg);
@@ -29,7 +25,6 @@ static int tmm_get_device_cert(struct cca_device_cert __user *arg); 


static const struct file_operations tmm_tsi_fops = {

	.owner          = THIS_MODULE,

	.read           = tmm_token_read,

	.unlocked_ioctl = tmm_tsi_ioctl

};
@@ -54,7 +49,7 @@ static int __init tmm_tsi_init(void) 
	}



	/* Allocate a large memory */

	token.buf = kzalloc(GRANULE_SIZE * MAX_TOKEN_GRANULE_PAGE, GFP_KERNEL);

	token.buf = kzalloc(GRANULE_SIZE * MAX_TOKEN_GRANULE_COUNT, GFP_KERNEL);

	if (!token.buf)

		return -ENOMEM;
@@ -68,7 +63,7 @@ static int __init tmm_tsi_init(void) 
static void __exit tmm_tsi_exit(void)

{

	if (token.buf != NULL) {

		memset(token.buf, 0, GRANULE_SIZE * MAX_TOKEN_GRANULE_PAGE);

		memset(token.buf, 0, GRANULE_SIZE * MAX_TOKEN_GRANULE_COUNT);

		kfree(token.buf);

	}

	misc_deregister(&ioctl_dev);
@@ -97,32 +92,6 @@ static long tmm_tsi_ioctl(struct file *file, unsigned int cmd, unsigned long arg 
	return ret;

}



static ssize_t tmm_token_read(struct file *file, char __user *user_buffer,

	size_t size, loff_t *offset)

{

	int ret;

	int to_copy;



	mutex_lock(&token_lock);

	if (*offset >= token.size) {

		mutex_unlock(&token_lock);

		return 0;

	}



	to_copy = min((int)size, (int)(token.size - *offset));

	ret = copy_to_user(user_buffer, token.buf + *offset, to_copy);

	if (ret) {

		pr_err("tmm_tsi: copy token to user failed (%d)!\n", ret);

		mutex_unlock(&token_lock);

		return -1;

	}



	*offset += to_copy;

	mutex_unlock(&token_lock);

	return to_copy;

}





static int tmm_get_tsi_version(struct cvm_tsi_version __user *arg)

{

	struct cvm_tsi_version ver_measured = {0};
@@ -150,7 +119,7 @@ static int tmm_get_attestation_token(struct cvm_attestation_cmd __user *arg) 


	ret = copy_from_user(challenge, &(arg->challenge), CHALLENGE_SIZE);

	if (ret) {

		pr_err("tmm_tsi: copy data from user failed (%lu)!\n", ret);

		pr_err("tmm_tsi: copy challenge from user failed (%lu)!\n", ret);

		return -EFAULT;

	}
@@ -166,8 +135,13 @@ static int tmm_get_attestation_token(struct cvm_attestation_cmd __user *arg) 
	}



	do { /* Retrieve one Granule of data per loop iteration */

		token_granule.ipa = token_granule.head +

			(unsigned long)(token_granule.count * GRANULE_SIZE);

		if (token_granule.count + 1 > MAX_TOKEN_GRANULE_COUNT) {

			pr_err("tmm_tsi: macro MAX_TOKEN_GRANULE_COUNT (%d) is too small!\n",

				MAX_TOKEN_GRANULE_COUNT);

			mutex_unlock(&token_lock);

			return -ENOMEM;

		}

		token_granule.ipa = token_granule.head + (token_granule.count * GRANULE_SIZE);

		token_granule.offset = 0;



		do { /* Retrieve sub-Granule chunk of data per loop iteration */
@@ -176,23 +150,23 @@ static int tmm_get_attestation_token(struct cvm_attestation_cmd __user *arg) 
			token_granule.offset += token_granule.num_wr_bytes;

		} while (ret == TSI_INCOMPLETE && token_granule.offset < GRANULE_SIZE);



		token_granule.count += 1;

		if (token_granule.count >= MAX_TOKEN_GRANULE_PAGE && ret == TSI_INCOMPLETE) {

			pr_err("tmm_tsi: macro MAX_TOKEN_GRANULE_PAGE (%d) is too small!\n",

				MAX_TOKEN_GRANULE_PAGE);

			mutex_unlock(&token_lock);

			return -ENOMEM;

		}

		token_granule.count++;



	} while (ret == TSI_INCOMPLETE);



	/* Send to user space the total size of the token */

	token_granule.count = token_granule.count - 1;

	token.size = (unsigned long)(GRANULE_SIZE * token_granule.count) + token_granule.offset;

	token.size = (GRANULE_SIZE * (token_granule.count - 1)) + token_granule.offset;



	ret = copy_to_user(&(arg->token_size), &(token.size), sizeof(token.size));

	if (ret) {

		pr_err("tmm_tsi: copy data to user failed (%lu)!\n", ret);

		pr_err("tmm_tsi: copy token_size to user failed (%lu)!\n", ret);

		mutex_unlock(&token_lock);

		return -EFAULT;

	}



	ret = copy_to_user(arg->token, token.buf, token.size);

	if (ret) {

		pr_err("tmm_tsi: copy token to user failed (%lu)!\n", ret);

		mutex_unlock(&token_lock);

		return -EFAULT;

	}