tpm: Handle negative priv->response_len in tpm_common_read()

The priv->response_length can hold the size of an response or an negative
error code, and the tpm_common_read() needs to handle both cases correctly.
Changed the type of response_length to signed and accounted for negative
value in tpm_common_read().

Cc: stable@vger.kernel.org
Fixes: d23d124843 ("tpm: fix invalid locking in NONBLOCKING mode")
Reported-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
This commit is contained in:
Tadeusz Struk 2020-01-07 14:04:48 -08:00 committed by Jarkko Sakkinen
parent ae6088216c
commit a430e67d9a
2 changed files with 2 additions and 2 deletions

View File

@ -130,7 +130,7 @@ ssize_t tpm_common_read(struct file *file, char __user *buf,
priv->response_read = true;
ret_size = min_t(ssize_t, size, priv->response_length);
if (!ret_size) {
if (ret_size <= 0) {
priv->response_length = 0;
goto out;
}

View File

@ -14,7 +14,7 @@ struct file_priv {
struct work_struct timeout_work;
struct work_struct async_work;
wait_queue_head_t async_wait;
size_t response_length;
ssize_t response_length;
bool response_read;
bool command_enqueued;