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).

Fixes: 66f909308a7c ("wifi: brcmfmac: cyw: support external SAE authentication in station mode")
Signed-off-by: Bogdan Nicolae <bogdan.nicolae@gmail.com>
Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>
---
v4: Fixed indentation
v3: Added Fixes, Cc: stable, and Acked-by tags
v2: Split into a separate patch

 drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
index 873754be5..2c59b5e57 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
@@ -200,7 +200,7 @@ 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 +208,8 @@ 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

On 04/08/2026 08:08, Bogdan Nicolae wrote:
> 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).
> 
> Fixes: 66f909308a7c ("wifi: brcmfmac: cyw: support external SAE authentication in station mode")
> Signed-off-by: Bogdan Nicolae <bogdan.nicolae@gmail.com>
> Acked-by: Arend van Spriel <arend.vanspriel@broadcom.com>

The checkpatch results on patchwork still show one failure [1].

Regards,
Arend

[1] 
https://netdev-ctrl.bots.linux.dev/logview.html?f=/logs/build-wireless/1139831/14729070/checkpatch/stdout

> ---
> v4: Fixed indentation
> v3: Added Fixes, Cc: stable, and Acked-by tags
> v2: Split into a separate patch
> 
>   drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c | 4 +++-
>   1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
> index 873754be5..2c59b5e57 100644
> --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
> +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cyw/core.c
> @@ -200,7 +200,7 @@ 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 +208,8 @@ 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);

The line above exceeds the 80 column limit.

>   		auth_status.flags = cpu_to_le16(BRCMF_EXTAUTH_SUCCESS);
>   	} else {
>   		bphy_err(drvr, "External authentication failed: status=%d\n",