[PATCH] wifi: brcmfmac: cyw: clean up PMKID and cookie code

From: bogdan . nicolae

Date: Tue Jul 14 2026 - 11:08:58 EST


From: Bogdan Nicolae <bogdan.nicolae@xxxxxxx>

Avoid setting packet_id to cookie, which is always 0. Instead, use an
increasing atomic counter. Avoids mismatches of completion events later
in brcmf_notify_mgmt_tx_status, where packet_id != vif->mgmt_tx_id is
checked.

Also, zero out auth_status on initialization. Otherwise, garbage will
leak from the stack to the firmware (when ssid is less than 32 bytes
and/or when params->pmkid is set). Then, pass the params->pmkid to the
firmware (without it, the firmware caches a garbage PMKID on successful
authentication and denies a subsequent association request that includes
the PMKID).

Signed-off-by: Bogdan Nicolae <bogdan.nicolae@xxxxxxx>
---
.../net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
index ce09d44fa..99f8c5bef 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
@@ -23,6 +23,8 @@
#define MGMT_AUTH_FRAME_DWELL_TIME 4000
#define MGMT_AUTH_FRAME_WAIT_TIME (MGMT_AUTH_FRAME_DWELL_TIME + 100)

+static atomic_t brcmf_cyw_mgmt_tx_id = ATOMIC_INIT(0);
+
static int brcmf_cyw_set_sae_pwd(struct brcmf_if *ifp,
struct cfg80211_crypto_settings *crypto)
{
@@ -123,7 +125,7 @@ int brcmf_cyw_mgmt_tx(struct wiphy *wiphy, struct wireless_dev *wdev,
if (!ieee80211_is_auth(mgmt->frame_control))
return brcmf_cfg80211_mgmt_tx(wiphy, wdev, params, cookie);

- *cookie = 0;
+ *cookie = atomic_inc_return(&brcmf_cyw_mgmt_tx_id);
vif = container_of(wdev, struct brcmf_cfg80211_vif, wdev);

reinit_completion(&vif->mgmt_tx);
@@ -200,7 +202,7 @@ brcmf_cyw_external_auth(struct wiphy *wiphy, struct net_device *dev,
{
struct brcmf_if *ifp;
struct brcmf_pub *drvr;
- struct brcmf_auth_req_status_le auth_status;
+ struct brcmf_auth_req_status_le auth_status = {};
int ret = 0;

brcmf_dbg(TRACE, "Enter\n");
@@ -208,6 +210,8 @@ brcmf_cyw_external_auth(struct wiphy *wiphy, struct net_device *dev,
ifp = netdev_priv(dev);
drvr = ifp->drvr;
if (params->status == WLAN_STATUS_SUCCESS) {
+ if (params->pmkid)
+ memcpy(auth_status.pmkid, params->pmkid, WLAN_PMKID_LEN);
auth_status.flags = cpu_to_le16(BRCMF_EXTAUTH_SUCCESS);
} else {
bphy_err(drvr, "External authentication failed: status=%d\n",
--
2.55.0