Hello Colin,
On Fri, Jul 09, 2021 at 03:53:39PM +0100, Colin Ian King wrote:
> Hi,
>
> Static analysis with Coverity has found an issue introduced by the
> following commit:
>
> commit 5befa937e8daaebcde81b9423eb93f3ff2e918f7
> Author: Quytelda Kahja <quytelda@xxxxxxxxxxx>
> Date: Tue Mar 27 01:41:02 2018 -0700
>
> staging: rtl8723bs: Fix IEEE80211 authentication algorithm constants.
>
> The analysis is as follows:
>
> 347 static int wpa_set_auth_algs(struct net_device *dev, u32 value)
> 348 {
> 349 struct adapter *padapter = rtw_netdev_priv(dev);
> 350 int ret = 0;
> 351
> 352 if ((value & WLAN_AUTH_SHARED_KEY) && (value & WLAN_AUTH_OPEN)) {
>
> Logically dead code (DEADCODE)
>
> 353 padapter->securitypriv.ndisencryptstatus =
> Ndis802_11Encryption1Enabled;
> 354 padapter->securitypriv.ndisauthtype =
> Ndis802_11AuthModeAutoSwitch;
> 355 padapter->securitypriv.dot11AuthAlgrthm =
> dot11AuthAlgrthm_Auto;
> 356 } else if (value & WLAN_AUTH_SHARED_KEY) {
> 357 padapter->securitypriv.ndisencryptstatus =
> Ndis802_11Encryption1Enabled;
> 358
> 359 padapter->securitypriv.ndisauthtype =
> Ndis802_11AuthModeShared;
> 360 padapter->securitypriv.dot11AuthAlgrthm =
> dot11AuthAlgrthm_Shared;
> dead_error_condition: The condition value & 0U cannot be true.
> 361 } else if (value & WLAN_AUTH_OPEN) {
> 362 /* padapter->securitypriv.ndisencryptstatus =
> Ndis802_11EncryptionDisabled; */
>
> Logically dead code (DEADCODE)
>
> 363 if (padapter->securitypriv.ndisauthtype <
> Ndis802_11AuthModeWPAPSK) {
> 364 padapter->securitypriv.ndisauthtype =
> Ndis802_11AuthModeOpen;
> 365 padapter->securitypriv.dot11AuthAlgrthm =
> dot11AuthAlgrthm_Open;
> 366 }
> 367 } else {
> 368 ret = -EINVAL;
> 369 }
> 370
> 371 return ret;
> 372
> 373 }
>
> The deadcode warnings occur because the mask value of WLAN_AUTH_OPEN is
> defined in /include/linux/ieee80211.h as:
>
> #define WLAN_AUTO_OPEN 0
>
> and so any value masked with 0 is 0 and hence that part of the if
> statement is always false.
>
> The original code was using the mask values:
>
> AUTH_ALG_SHARED_KEY and also AUTH_ALG_OPEN_SYSTEM that are defined as:
>
> #define AUTH_ALG_OPEN_SYSTEM 0x1
> #define AUTH_ALG_SHARED_KEY 0x2
I think that the correct macros are:
/* IW_AUTH_80211_AUTH_ALG values (bit field) */
#define IW_AUTH_ALG_OPEN_SYSTEM 0x00000001
#define IW_AUTH_ALG_SHARED_KEY 0x00000002
#define IW_AUTH_ALG_LEAP 0x00000004
defined in include/uapi/linux/wireless.h
>
> So this appears to be a regression. I'm not sure the best approach for a
> suitable fix to use the intended macros in ieee80211.h
>
> Colin
>
>
>
>
thank you,
fabio
