diff options
author | Peter Huewe <huewe.external.infineon@googlemail.com> | 2011-09-15 14:47:42 -0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-10-03 11:40:58 -0700 |
commit | 1d43a87614596faf4b9cae2d0c894aa67a7c5121 (patch) | |
tree | 95dacb9911e577b4a4284f0951fc646eb8a48ee0 /drivers/char | |
parent | 108885cc2856128a266423d45f617e65961048f7 (diff) |
TPM: Zero buffer after copying to userspace
commit 3321c07ae5068568cd61ac9f4ba749006a7185c9 upstream.
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>
Signed-off-by: James Morris <jmorris@namei.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/char')
-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 92676292bea..b85ee76e4b4 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -1055,6 +1055,7 @@ 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); @@ -1065,8 +1066,11 @@ 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); } |