Errors in sending nullfunc or probe request frames during off-channel
operation may have undesirable consequences, e.g. failure to set
powersave at the AP. Add error handling for failures to transmit these
frames. In the case of a nullfunc failure, fail to go off-channel and
return an error to userspace. In the case of a failed probe request,
abort the scan.
Signed-off-by: Seth Forshee <seth.forshee@xxxxxxxxxxxxx>
---
net/mac80211/ieee80211_i.h | 6 +++---
net/mac80211/mlme.c | 6 +++---
net/mac80211/offchannel.c | 24 ++++++++++++++++++------
net/mac80211/scan.c | 41 ++++++++++++++++++++++++++++-------------
net/mac80211/util.c | 12 ++++++++----
5 files changed, 60 insertions(+), 29 deletions(-)
diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h
index 8374763..c062d20 100644
--- a/net/mac80211/ieee80211_i.h
+++ b/net/mac80211/ieee80211_i.h
@@ -1369,7 +1369,7 @@ int ieee80211_request_sched_scan_stop(struct ieee80211_sub_if_data *sdata);
void ieee80211_sched_scan_stopped_work(struct work_struct *work);
/* off-channel helpers */
-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local);
+bool ieee80211_offchannel_stop_vifs(struct ieee80211_local *local);
void ieee80211_offchannel_return(struct ieee80211_local *local);
void ieee80211_roc_setup(struct ieee80211_local *local);
void ieee80211_start_next_roc(struct ieee80211_local *local);
@@ -1582,7 +1582,7 @@ u32 ieee80211_mandatory_rates(struct ieee80211_local *local,
void ieee80211_dynamic_ps_enable_work(struct work_struct *work);
void ieee80211_dynamic_ps_disable_work(struct work_struct *work);
void ieee80211_dynamic_ps_timer(unsigned long data);
-void ieee80211_send_nullfunc(struct ieee80211_local *local,
+bool ieee80211_send_nullfunc(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata,
int powersave);
void ieee80211_sta_rx_notify(struct ieee80211_sub_if_data *sdata,
@@ -1627,7 +1627,7 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
const u8 *ssid, size_t ssid_len,
const u8 *ie, size_t ie_len,
bool directed);
-void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
+bool ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
const u8 *ssid, size_t ssid_len,
const u8 *ie, size_t ie_len,
u32 ratemask, bool directed, bool no_cck,
diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 6757ee2..7211344 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -664,7 +664,7 @@ void ieee80211_send_pspoll(struct ieee80211_local *local,
ieee80211_tx_skb(sdata, skb);
}
-void ieee80211_send_nullfunc(struct ieee80211_local *local,
+bool ieee80211_send_nullfunc(struct ieee80211_local *local,
struct ieee80211_sub_if_data *sdata,
int powersave)
{
@@ -674,7 +674,7 @@ void ieee80211_send_nullfunc(struct ieee80211_local *local,
skb = ieee80211_nullfunc_get(&local->hw, &sdata->vif);
if (!skb)
- return;
+ return false;
nullfunc = (struct ieee80211_hdr_3addr *) skb->data;
if (powersave)
@@ -685,7 +685,7 @@ void ieee80211_send_nullfunc(struct ieee80211_local *local,
IEEE80211_STA_CONNECTION_POLL))
IEEE80211_SKB_CB(skb)->flags |= IEEE80211_TX_CTL_USE_MINRATE;
- ieee80211_tx_skb_offchannel(sdata, skb);
+ return ieee80211_tx_skb_offchannel(sdata, skb) == IEEE80211_TX_OK;
}
static void ieee80211_send_4addr_nullfunc(struct ieee80211_local *local,
diff --git a/net/mac80211/offchannel.c b/net/mac80211/offchannel.c
index 5b9b3b8..650af94 100644
--- a/net/mac80211/offchannel.c
+++ b/net/mac80211/offchannel.c
@@ -24,10 +24,11 @@
* because we *may* be doing work on-operating channel, and want our
* hardware unconditionally awake, but still let the AP send us normal frames.
*/
-static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
+static bool ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
{
struct ieee80211_local *local = sdata->local;
struct ieee80211_if_managed *ifmgd = &sdata->u.mgd;
+ bool ret = true;
local->offchannel_ps_enabled = false;
@@ -57,7 +58,9 @@ static void ieee80211_offchannel_ps_enable(struct ieee80211_sub_if_data *sdata)
* to send a new nullfunc frame to inform the AP that we
* are again sleeping.
*/
- ieee80211_send_nullfunc(local, sdata, 1);
+ ret = ieee80211_send_nullfunc(local, sdata, 1);
+
+ return ret;
}
/* inform AP that we are awake again, unless power save is enabled */
@@ -102,12 +105,13 @@ static void ieee80211_offchannel_ps_disable(struct ieee80211_sub_if_data *sdata)
ieee80211_sta_reset_conn_monitor(sdata);
}
-void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
+bool ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
{
struct ieee80211_sub_if_data *sdata;
+ bool ret = true;
if (WARN_ON(local->use_chanctx))
- return;
+ return false;
/*
* notify the AP about us leaving the channel and stop all
@@ -138,10 +142,18 @@ void ieee80211_offchannel_stop_vifs(struct ieee80211_local *local)
}
if (sdata->vif.type == NL80211_IFTYPE_STATION &&
- sdata->u.mgd.associated)
- ieee80211_offchannel_ps_enable(sdata);
+ sdata->u.mgd.associated) {
+ ret = ieee80211_offchannel_ps_enable(sdata);
+ if (!ret)
+ break;
+ }
}
mutex_unlock(&local->iflist_mtx);
+
+ /* Attempt to recover if failed */
+ if (!ret)
+ ieee80211_offchannel_return(local);
+ return ret;
}
void ieee80211_offchannel_return(struct ieee80211_local *local)
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 607684c..894c95e 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -340,7 +340,8 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
local->next_scan_state = SCAN_DECISION;
local->scan_channel_idx = 0;
- ieee80211_offchannel_stop_vifs(local);
+ if (!ieee80211_offchannel_stop_vifs(local))
+ goto error;
ieee80211_configure_filter(local);
@@ -351,6 +352,10 @@ static int ieee80211_start_sw_scan(struct ieee80211_local *local)
&local->scan_work, 0);
return 0;
+
+error:
+ drv_sw_scan_complete(local);
+ return -EBUSY;
}
static bool ieee80211_can_scan(struct ieee80211_local *local,
@@ -390,26 +395,32 @@ static void ieee80211_scan_state_send_probe(struct ieee80211_local *local,
int i;
struct ieee80211_sub_if_data *sdata;
enum ieee80211_band band = local->hw.conf.channel->band;
+ bool success = true;
sdata = rcu_dereference_protected(local->scan_sdata,
lockdep_is_held(&local->mtx));
- for (i = 0; i < local->scan_req->n_ssids; i++)
- ieee80211_send_probe_req(
- sdata, NULL,
- local->scan_req->ssids[i].ssid,
- local->scan_req->ssids[i].ssid_len,
- local->scan_req->ie, local->scan_req->ie_len,
- local->scan_req->rates[band], false,
- local->scan_req->no_cck,
- local->hw.conf.channel, true);
+ for (i = 0; success && i < local->scan_req->n_ssids; i++)
+ success = ieee80211_send_probe_req(
+ sdata, NULL,
+ local->scan_req->ssids[i].ssid,
+ local->scan_req->ssids[i].ssid_len,
+ local->scan_req->ie, local->scan_req->ie_len,
+ local->scan_req->rates[band], false,
+ local->scan_req->no_cck,
+ local->hw.conf.channel, true);
/*
* After sending probe requests, wait for probe responses
* on the channel.
*/
- *next_delay = IEEE80211_CHANNEL_TIME;
- local->next_scan_state = SCAN_DECISION;
+ if (success) {
+ *next_delay = IEEE80211_CHANNEL_TIME;
+ local->next_scan_state = SCAN_DECISION;
+ } else {
+ *next_delay = 0;
+ local->next_scan_state = SCAN_ABORT;
+ }
}
static int __ieee80211_start_scan(struct ieee80211_sub_if_data *sdata,
@@ -688,7 +699,11 @@ static void ieee80211_scan_state_suspend(struct ieee80211_local *local,
static void ieee80211_scan_state_resume(struct ieee80211_local *local,
unsigned long *next_delay)
{
- ieee80211_offchannel_stop_vifs(local);
+ if (!ieee80211_offchannel_stop_vifs(local)) {
+ *next_delay = 0;
+ local->next_scan_state = SCAN_ABORT;
+ return;
+ }
if (local->ops->flush) {
drv_flush(local, false);
diff --git a/net/mac80211/util.c b/net/mac80211/util.c
index 5259557..0923892 100644
--- a/net/mac80211/util.c
+++ b/net/mac80211/util.c
@@ -1274,13 +1274,14 @@ struct sk_buff *ieee80211_build_probe_req(struct ieee80211_sub_if_data *sdata,
return skb;
}
-void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
+bool ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
const u8 *ssid, size_t ssid_len,
const u8 *ie, size_t ie_len,
u32 ratemask, bool directed, bool no_cck,
struct ieee80211_channel *channel, bool scan)
{
struct sk_buff *skb;
+ enum ieee80211_tx_status tx_stat = IEEE80211_TX_DROPPED;
skb = ieee80211_build_probe_req(sdata, dst, ratemask, channel,
ssid, ssid_len,
@@ -1290,11 +1291,14 @@ void ieee80211_send_probe_req(struct ieee80211_sub_if_data *sdata, u8 *dst,
IEEE80211_SKB_CB(skb)->flags |=
IEEE80211_TX_CTL_NO_CCK_RATE;
if (scan)
- ieee80211_tx_skb_tid_band(sdata, skb, 7,
- channel->band, true);
+ tx_stat = ieee80211_tx_skb_tid_band(sdata, skb, 7,
+ channel->band,
+ true);
else
- ieee80211_tx_skb(sdata, skb);
+ tx_stat = ieee80211_tx_skb(sdata, skb);
}
+
+ return tx_stat != IEEE80211_TX_DROPPED;
}
u32 ieee80211_sta_get_rates(struct ieee80211_local *local,
--
1.7.9.5
--
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