diff options
author | Peter Huewe <huewe.external.infineon@googlemail.com> | 2011-09-15 14:47:42 -0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2011-11-07 12:32:06 -0800 |
commit | 8cef0aa080f3f7c443f1380f5b1fba63859e757a (patch) | |
tree | 5e9921aa3ada9c2b29d7c811bb8b8af80ee65b93 /drivers | |
parent | f891a7b01eed6b941627f5049b439da368d76fa3 (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')
-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 78cb0b3a96d3..a0789f682e14 100644 --- a/drivers/char/tpm/tpm.c +++ b/drivers/char/tpm/tpm.c @@ -1044,6 +1044,7 @@ 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_scheduled_work(); @@ -1054,8 +1055,11 @@ 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); } |