diff options
| author | Peter Huewe <huewe.external.infineon@googlemail.com> | 2011-09-15 19:47:42 +0200 |
|---|---|---|
| committer | James Morris <jmorris@namei.org> | 2011-09-23 01:46:41 +0200 |
| commit | 3321c07ae5068568cd61ac9f4ba749006a7185c9 (patch) | |
| tree | bcd169e21c2f71651ab840ee77152094db0c3deb /drivers | |
| parent | TPM: Call tpm_transmit with correct size (diff) | |
| download | linux-3321c07ae5068568cd61ac9f4ba749006a7185c9.tar.xz linux-3321c07ae5068568cd61ac9f4ba749006a7185c9.zip | |
TPM: Zero buffer after copying to userspace
Since the buffer might contain security related data it might be a good idea to
zero the buffer after we have copied it to userspace.
This got assigned CVE-2011-1162.
Signed-off-by: Rajiv Andrade <srajiv@linux.vnet.ibm.com>
Cc: Stable Kernel <stable@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/char/tpm/tpm.c | 6 |
1 files changed, 5 insertions, 1 deletions
diff --git a/drivers/char/tpm/tpm.c b/drivers/char/tpm/tpm.c index 1fe979335835..9ca5c021d0b6 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -1105,6 +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); @@ -1115,8 +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); } |