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From:   Koen Vandeputte <koen.vandeputte@citymesh.com>
To:     linux-wireless@vger.kernel.org
Cc:     Koen Vandeputte <koen.vandeputte@citymesh.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        John Crispin <john@phrozen.org>,
        Aloka Dixit <alokad@codeaurora.org>, stable@vger.kernel.org
Subject: [PATCH] wifi: nl80211: fix mbssid nesting
Date:   Wed, 12 Jul 2023 10:38:41 +0200
Message-Id: <20230712083841.222607-1-koen.vandeputte@citymesh.com>
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Executing command NL80211_CMD_GET_WIPHY and parsing it's output
natively without libnl shows following attributes as part of
the nl80211 generated netlink message (part 16):

GetWiphy: Type: 1
GetWiphy: Type: 2
GetWiphy: Type: 46
GetWiphy: Type: 33074 <-- wrong enum value, above MAX also ..
GetWiphy: Type: 316

Switching to nla_nest_start_noflag() which ommits the NLA_F_NESTED
flag (like most other similar functions do) fixes this:

GetWiphy: Type: 1
GetWiphy: Type: 2
GetWiphy: Type: 46
GetWiphy: Type: 306 <-- correct enum value
GetWiphy: Type: 316

Fixes: dc1e3cb8da8b ("nl80211: MBSSID and EMA support in AP mode")
Signed-off-by: Koen Vandeputte <koen.vandeputte@citymesh.com>
Cc: Johannes Berg <johannes@sipsolutions.net>
Cc: John Crispin <john@phrozen.org>
Cc: Aloka Dixit <alokad@codeaurora.org>
Cc: stable@vger.kernel.org # 5.16
---
 net/wireless/nl80211.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 0da2e6a2a7ea..4d4860f9428d 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2359,7 +2359,7 @@ static int nl80211_put_mbssid_support(struct wiphy *wiphy, struct sk_buff *msg)
 	if (!wiphy->mbssid_max_interfaces)
 		return 0;
 
-	config = nla_nest_start(msg, NL80211_ATTR_MBSSID_CONFIG);
+	config = nla_nest_start_noflag(msg, NL80211_ATTR_MBSSID_CONFIG);
 	if (!config)
 		return -ENOBUFS;
 
-- 
2.34.1