1 files changed, 8 insertions, 1 deletions

diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c
index caf8012ef47c..9ca5c021d0b6 100644
--- a/drivers/char/tpm/tpm.c
+++ b/drivers/char/tpm/tpm.c
@@ -383,6 +383,9 @@ static ssize_t tpm_transmit(struct tpm_chip *chip, const char *buf,
         u32 count, ordinal;
         unsigned long stop;
 
+        if (bufsiz > TPM_BUFSIZE)
+                bufsiz = TPM_BUFSIZE;
+
         count = be32_to_cpu(*((__be32 *) (buf + 2)));
         ordinal = be32_to_cpu(*((__be32 *) (buf + 6)));
         if (count == 0)
@@ -1102,6 +1105,7 @@ ssize_t tpm_read(struct file *file, char __user *buf,
 {
         struct tpm_chip *chip = file->private_data;
         ssize_t ret_size;
+        int rc;
 
         del_singleshot_timer_sync(&chip->user_read_timer);
         flush_work_sync(&chip->work);
@@ -1112,8 +1116,11 @@ ssize_t tpm_read(struct file *file, char __user *buf,
                         ret_size = size;
 
                 mutex_lock(&chip->buffer_mutex);
-                if (copy_to_user(buf, chip->data_buffer, ret_size))
+                rc = copy_to_user(buf, chip->data_buffer, ret_size);
+                memset(chip->data_buffer, 0, ret_size);
+                if (rc)
                         ret_size = -EFAULT;
+
                 mutex_unlock(&chip->buffer_mutex);
         }