To remove the dependency to rtnl_lock() for
ieee80211_vif_use/release_channel in AP mode, protect the AP_VLAN
list with local->iflist_mtx instead.
RTNL can not be used from within mac80211 workers, but the
DFS AP interface requires to release channels (after DFS channel
availability checks).
Signed-off-by: Simon Wunderlich <siwu@xxxxxxxxxxxxxxxxxx>
---
net/mac80211/cfg.c | 14 ++++++++++++++
net/mac80211/chan.c | 4 ++--
net/mac80211/ieee80211_i.h | 2 ++
net/mac80211/iface.c | 11 ++++++++++-
4 files changed, 28 insertions(+), 3 deletions(-)
diff --git a/net/mac80211/cfg.c b/net/mac80211/cfg.c
index 661b878..4a99a8f 100644
--- a/net/mac80211/cfg.c
+++ b/net/mac80211/cfg.c
@@ -923,8 +923,10 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
sdata->smps_mode = IEEE80211_SMPS_OFF;
sdata->needed_rx_chains = sdata->local->rx_chains;
+ mutex_lock(&sdata->local->iflist_mtx);
err = ieee80211_vif_use_channel(sdata, ¶ms->chandef,
IEEE80211_CHANCTX_SHARED);
+ mutex_unlock(&sdata->local->iflist_mtx);
if (err)
return err;
@@ -934,12 +936,14 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
*/
sdata->control_port_protocol = params->crypto.control_port_ethertype;
sdata->control_port_no_encrypt = params->crypto.control_port_no_encrypt;
+ mutex_lock(&sdata->local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list) {
vlan->control_port_protocol =
params->crypto.control_port_ethertype;
vlan->control_port_no_encrypt =
params->crypto.control_port_no_encrypt;
}
+ mutex_unlock(&sdata->local->iflist_mtx);
sdata->vif.bss_conf.beacon_int = params->beacon_interval;
sdata->vif.bss_conf.dtim_period = params->dtim_period;
@@ -972,8 +976,10 @@ static int ieee80211_start_ap(struct wiphy *wiphy, struct net_device *dev,
ieee80211_bss_info_change_notify(sdata, changed);
netif_carrier_on(dev);
+ mutex_lock(&sdata->local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
netif_carrier_on(vlan->dev);
+ mutex_unlock(&sdata->local->iflist_mtx);
return 0;
}
@@ -1012,8 +1018,10 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
old_probe_resp = rtnl_dereference(sdata->u.ap.probe_resp);
/* turn off carrier for this interface and dependent VLANs */
+ mutex_lock(&local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
netif_carrier_off(vlan->dev);
+ mutex_unlock(&local->iflist_mtx);
netif_carrier_off(dev);
/* remove beacon and probe response */
@@ -1023,12 +1031,16 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
if (old_probe_resp)
kfree_rcu(old_probe_resp, rcu_head);
+ mutex_lock(&local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
sta_info_flush_defer(vlan);
+ mutex_unlock(&local->iflist_mtx);
sta_info_flush_defer(sdata);
rcu_barrier();
+ mutex_lock(&local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
sta_info_flush_cleanup(vlan);
+ mutex_unlock(&local->iflist_mtx);
sta_info_flush_cleanup(sdata);
sdata->vif.bss_conf.enable_beacon = false;
@@ -1041,7 +1053,9 @@ static int ieee80211_stop_ap(struct wiphy *wiphy, struct net_device *dev)
local->total_ps_buffered -= skb_queue_len(&sdata->u.ap.ps.bc_buf);
skb_queue_purge(&sdata->u.ap.ps.bc_buf);
+ mutex_lock(&local->iflist_mtx);
ieee80211_vif_release_channel(sdata);
+ mutex_unlock(&local->iflist_mtx);
return 0;
}
diff --git a/net/mac80211/chan.c b/net/mac80211/chan.c
index 1bfe0a8..cbdc999 100644
--- a/net/mac80211/chan.c
+++ b/net/mac80211/chan.c
@@ -202,7 +202,7 @@ static void __ieee80211_vif_release_channel(struct ieee80211_sub_if_data *sdata)
struct ieee80211_sub_if_data *vlan;
/* for the VLAN list */
- ASSERT_RTNL();
+ lockdep_assert_held(&local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
rcu_assign_pointer(vlan->vif.chanctx_conf, NULL);
}
@@ -330,7 +330,7 @@ int ieee80211_vif_use_channel(struct ieee80211_sub_if_data *sdata,
struct ieee80211_sub_if_data *vlan;
/* for the VLAN list */
- ASSERT_RTNL();
+ lockdep_assert_held(&local->iflist_mtx);
list_for_each_entry(vlan, &sdata->u.ap.vlans, u.vlan.list)
rcu_assign_pointer(vlan->vif.chanctx_conf, &ctx->conf);
}
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 5fba867..b619cf7 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -294,6 +294,7 @@ struct ieee80211_if_ap {
struct beacon_data __rcu *beacon;
struct probe_resp __rcu *probe_resp;
+ /* protected with local->iflist_mtx */
struct list_head vlans;
struct ps_data ps;
@@ -306,6 +307,7 @@ struct ieee80211_if_wds {
};
struct ieee80211_if_vlan {
+ /* protected with local->iflist_mtx */
struct list_head list;
/* used for all tx if the VLAN is configured to 4-addr mode */
diff --git a/net/mac80211/iface.c b/net/mac80211/iface.c
index 0a36dc6..dbb7fed 100644
--- a/net/mac80211/iface.c
+++ b/net/mac80211/iface.c
@@ -517,7 +517,9 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
if (!sdata->bss)
return -ENOLINK;
+ mutex_lock(&local->iflist_mtx);
list_add(&sdata->u.vlan.list, &sdata->bss->vlans);
+ mutex_unlock(&local->iflist_mtx);
master = container_of(sdata->bss,
struct ieee80211_sub_if_data, u.ap);
@@ -717,8 +719,11 @@ int ieee80211_do_open(struct wireless_dev *wdev, bool coming_up)
drv_stop(local);
err_del_bss:
sdata->bss = NULL;
- if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+ if (sdata->vif.type == NL80211_IFTYPE_AP_VLAN) {
+ mutex_lock(&sdata->local->iflist_mtx);
list_del(&sdata->u.vlan.list);
+ mutex_unlock(&sdata->local->iflist_mtx);
+ }
/* might already be clear but that doesn't matter */
clear_bit(SDATA_STATE_RUNNING, &sdata->state);
return res;
@@ -821,10 +826,12 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
if (sdata->vif.type == NL80211_IFTYPE_AP) {
struct ieee80211_sub_if_data *vlan, *tmpsdata;
+ mutex_lock(&local->iflist_mtx);
/* down all dependent devices, that is VLANs */
list_for_each_entry_safe(vlan, tmpsdata, &sdata->u.ap.vlans,
u.vlan.list)
dev_close(vlan->dev);
+ mutex_unlock(&local->iflist_mtx);
WARN_ON(!list_empty(&sdata->u.ap.vlans));
} else if (sdata->vif.type == NL80211_IFTYPE_STATION) {
ieee80211_mgd_stop(sdata);
@@ -835,7 +842,9 @@ static void ieee80211_do_stop(struct ieee80211_sub_if_data *sdata,
switch (sdata->vif.type) {
case NL80211_IFTYPE_AP_VLAN:
+ mutex_lock(&sdata->local->iflist_mtx);
list_del(&sdata->u.vlan.list);
+ mutex_unlock(&sdata->local->iflist_mtx);
rcu_assign_pointer(sdata->vif.chanctx_conf, NULL);
/* no need to tell driver */
break;
--
1.7.10.4
--
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