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

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Fix token error issue when concurrent calls

Fixes: 31071f4b2a0b ("cvm_tsi: add cvm tsi interface") Signed-off-by: Shengjie Li lishengjie12@huawei.com --- arch/arm64/include/uapi/asm/cvm_tsi.h | 6 ++- arch/arm64/kernel/cvm_tsi.c | 66 ++++++++------------------- 2 files changed, 24 insertions(+), 48 deletions(-)

diff --git a/arch/arm64/include/uapi/asm/cvm_tsi.h b/arch/arm64/include/uapi/asm/cvm_tsi.h index 1ed4386db2..16f0e01598 100644 --- a/arch/arm64/include/uapi/asm/cvm_tsi.h +++ b/arch/arm64/include/uapi/asm/cvm_tsi.h @@ -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 */ };

diff --git a/arch/arm64/kernel/cvm_tsi.c b/arch/arm64/kernel/cvm_tsi.c index a020dc12a5..32406a8a38 100644 --- a/arch/arm64/kernel/cvm_tsi.c +++ b/arch/arm64/kernel/cvm_tsi.c @@ -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; }