Commit 52cebabb authored by Felix Fietkau's avatar Felix Fietkau Committed by Johannes Berg
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wifi: mac80211: fix vif addr when switching from monitor to station 



Since adding support for opting out of virtual monitor support, a zero vif
addr was used to indicate passive vs active monitor to the driver.
This would break the vif->addr when changing the netdev mac address before
switching the interface from monitor to sta mode.
Fix the regression by adding a separate flag to indicate whether vif->addr
is valid.

Reported-by: default avatar <syzbot+9ea265d998de25ac6a46@syzkaller.appspotmail.com>
Fixes: 9d40f7e3 ("wifi: mac80211: add flag to opt out of virtual monitor support")
Signed-off-by: default avatarFelix Fietkau <nbd@nbd.name>
Link: https://patch.msgid.link/20241115115850.37449-1-nbd@nbd.name


Signed-off-by: default avatarJohannes Berg <johannes.berg@intel.com>
parent 11ac0d7c

include/net/mac80211.h

+3 −0
Original line number Diff line number Diff line
@@ -1987,6 +1987,8 @@ enum ieee80211_neg_ttlm_res { 
 * @neg_ttlm: negotiated TID to link mapping info.

 *	see &struct ieee80211_neg_ttlm.

 * @addr: address of this interface

 * @addr_valid: indicates if the address is actively used. Set to false for

 *	passive monitor interfaces, true in all other cases.

 * @p2p: indicates whether this AP or STA interface is a p2p

 *	interface, i.e. a GO or p2p-sta respectively

 * @netdev_features: tx netdev features supported by the hardware for this
@@ -2026,6 +2028,7 @@ struct ieee80211_vif { 
	u16 valid_links, active_links, dormant_links, suspended_links;

	struct ieee80211_neg_ttlm neg_ttlm;

	u8 addr[ETH_ALEN] __aligned(2);

	bool addr_valid;

	bool p2p;



	u8 cab_queue;

net/mac80211/iface.c

+4 −7
Original line number Diff line number Diff line
@@ -278,13 +278,8 @@ static int _ieee80211_change_mac(struct ieee80211_sub_if_data *sdata, 
	ret = eth_mac_addr(sdata->dev, sa);



	if (ret == 0) {

		if (check_dup) {

		memcpy(sdata->vif.addr, sa->sa_data, ETH_ALEN);

		ether_addr_copy(sdata->vif.bss_conf.addr, sdata->vif.addr);

		} else {

			memset(sdata->vif.addr, 0, ETH_ALEN);

			memset(sdata->vif.bss_conf.addr, 0, ETH_ALEN);

		}

	}



	/* Regardless of eth_mac_addr() return we still want to add the
@@ -1323,6 +1318,8 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up) 
		}

	}



	sdata->vif.addr_valid = sdata->vif.type != NL80211_IFTYPE_MONITOR ||

				(sdata->u.mntr.flags & MONITOR_FLAG_ACTIVE);

	switch (sdata->vif.type) {

	case NL80211_IFTYPE_AP_VLAN:

		/* no need to tell driver, but set carrier and chanctx */