Code: static int orinoco_ioctl_set_auth(struct net_device *dev,
				  struct iw_request_info *info,
				  union iwreq_data *wrqu, char *extra)
{
	struct orinoco_private *priv = ndev_priv(dev);
	hermes_t *hw = &priv->hw;
	struct iw_param *param = &wrqu->param;
	unsigned long flags;
	int ret = -EINPROGRESS;

	if (orinoco_lock(priv, &flags) != 0)
		return -EBUSY;

	switch (param->flags & IW_AUTH_INDEX) {
	case IW_AUTH_WPA_VERSION:
	case IW_AUTH_CIPHER_PAIRWISE:
	case IW_AUTH_CIPHER_GROUP:
	case IW_AUTH_RX_UNENCRYPTED_EAPOL:
	case IW_AUTH_PRIVACY_INVOKED:
	case IW_AUTH_DROP_UNENCRYPTED:
		/*
		 * orinoco does not use these parameters
		 */
		break;

	case IW_AUTH_KEY_MGMT:
		/* wl_lkm implies value 2 == PSK for Hermes I
		 * which ties in with WEXT
		 * no other hints tho :(
		 */
		priv->key_mgmt = param->value;
		break;

	case IW_AUTH_TKIP_COUNTERMEASURES:
		/* When countermeasures are enabled, shut down the
		 * card; when disabled, re-enable the card. This must
		 * take effect immediately.
		 *
		 * TODO: Make sure that the EAPOL message is getting
		 *       out before card disabled
 		 */
 		if (param->value) {
 			priv->tkip_cm_active = 1;
			ret = hermes_enable_port(hw, 0);
 		} else {
 			priv->tkip_cm_active = 0;
			ret = hermes_disable_port(hw, 0);
 		}
 		break;
 
	case IW_AUTH_80211_AUTH_ALG:
		if (param->value & IW_AUTH_ALG_SHARED_KEY)
			priv->wep_restrict = 1;
		else if (param->value & IW_AUTH_ALG_OPEN_SYSTEM)
			priv->wep_restrict = 0;
		else
			ret = -EINVAL;
		break;

	case IW_AUTH_WPA_ENABLED:
		if (priv->has_wpa) {
			priv->wpa_enabled = param->value ? 1 : 0;
		} else {
			if (param->value)
				ret = -EOPNOTSUPP;
			/* else silently accept disable of WPA */
			priv->wpa_enabled = 0;
		}
		break;

	default:
		ret = -EOPNOTSUPP;
	}

	orinoco_unlock(priv, &flags);
	return ret;
}

Vulnerability Type: 
CWE ID: 
Summary: The orinoco_ioctl_set_auth function in drivers/net/wireless/orinoco/wext.c in the Linux kernel before 2.6.37 does not properly implement a TKIP protection mechanism, which makes it easier for remote attackers to obtain access to a Wi-Fi network by reading Wi-Fi frames.
Commit Message: orinoco: fix TKIP countermeasure behaviour

Enable the port when disabling countermeasures, and disable it on
enabling countermeasures.

This bug causes the response of the system to certain attacks to be
ineffective.

It also prevents wpa_supplicant from getting scan results, as
wpa_supplicant disables countermeasures on startup - preventing the
hardware from scanning.

wpa_supplicant works with ap_mode=2 despite this bug because the commit
handler re-enables the port.

The log tends to look like:

State: DISCONNECTED -> SCANNING
Starting AP scan for wildcard SSID
Scan requested (ret=0) - scan timeout 5 seconds
EAPOL: disable timer tick
EAPOL: Supplicant port status: Unauthorized
Scan timeout - try to get results
Failed to get scan results
Failed to get scan results - try scanning again
Setting scan request: 1 sec 0 usec
Starting AP scan for wildcard SSID
Scan requested (ret=-1) - scan timeout 5 seconds
Failed to initiate AP scan.

Reported by: Giacomo Comes <comes@naic.edu>
Signed-off by: David Kilroy <kilroyd@googlemail.com>
Cc: stable@kernel.org
Signed-off-by: John W. Linville <linville@tuxdriver.com>