brcmfmac-cyw: clean up PMKID and cookie code

[bnicolae]

Do not touch the cookie. Value 0 means any follow-up should be discarded downstream. Instead, set the packet_id directly. Also, zero out the whole auth_status data structure instead of just auth_status.pmkid, which is safer: other bytes than pmkid may leak from stack if ssid_len is less than 32, although the firmware is likely to ignore them. Do not rely on userspace to set params->pmkid only if authentication is successful (true for hostapd). Guard against it anyway.

[pelwell]

Is this the version you are sending upstream? It would be nice if it didn't change again.

[bnicolae]

Yes, that's precisely why I cleaned it up

[pelwell]

You ought to run checkpatch on it:

$ scripts/checkpatch.pl -g HEAD
WARNING: Prefer a maximum 75 chars per line (possible unwrapped commit description?)
#6: 
Do not touch the cookie. Value 0 means any follow-up should be discarded downstream. Instead, set the packet_id directly.

WARNING: suspect code indent for conditional statements (16, 20)
#51: FILE: drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c:215:
+               if (params->pmkid)
+                   memcpy(auth_status.pmkid, params->pmkid, WLAN_PMKID_LEN);

total: 0 errors, 2 warnings, 0 checks, 41 lines checked

NOTE: For some of the reported defects, checkpatch may be able to
      mechanically convert to the typical style using --fix or --fix-inplace.

Commit 5be64be2fa14 ("brcmfmac-cyw: clean up PMKID and cookie code") has style problems, please review.

[bnicolae]

Done, thanks for the checkpatch tip.

[pelwell]

Thank you for your contributions.