[PATCH 0/3] fix and improvements

[PATCH 0/3] fix and improvements

[Zhao, Gang]

I think the first patch should also be applied to 3.15.

Zhao, Gang (3):
  cfg80211: fix incorrect checking of return value
  cfg80211/mac80211: rename cfg80211_chandef_dfs_required()
  cfg80211: change variable name

 include/net/cfg80211.h |   6 +--
 net/mac80211/ibss.c    |  40 ++++++++---------
 net/mac80211/mesh.c    |  16 +++----
 net/wireless/chan.c    |  32 +++++++------
 net/wireless/mesh.c    |  22 ++++-----
 net/wireless/nl80211.c | 120 ++++++++++++++++++++++++-------------------------
 net/wireless/trace.h   |   2 +-
 7 files changed, 118 insertions(+), 120 deletions(-)

-- 
1.9.0

[PATCH 1/3] cfg80211: fix incorrect checking of return value

[Zhao, Gang]

Since cfg80211_chandef_dfs_required() can return error number(e.g.,
-EINVAL), it's not sufficient to just check if it didn't return zero.

Fixes: 9e0e29615a20 ("cfg80211: consider existing DFS interfaces")
Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
---
 net/wireless/chan.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 9c9501a..2cfff9e 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -744,7 +744,7 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chanmode = CHAN_MODE_SHARED;
 
 			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef))
+							  &wdev->chandef) > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
@@ -754,7 +754,7 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chanmode = CHAN_MODE_SHARED;
 
 			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef))
+							  &wdev->chandef) > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
-- 
1.9.0

[PATCH 2/3] cfg80211/mac80211: rename cfg80211_chandef_dfs_required()

[Zhao, Gang]

Change the name to cfg80211_chandef_dfs_check to emphasize that the
function isn't a yes/no function, its return value must be fully
checked.

Also rename the helper function's name to
cfg80211_do_chandef_dfs_check for consistency.

Variable width needn't to be checked for sanity, since above
cfg80211_chandef_valid() already checked the sanity of chandef->width.

Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
---
 include/net/cfg80211.h |  6 +++---
 net/mac80211/ibss.c    | 12 ++++++------
 net/mac80211/mesh.c    |  4 ++--
 net/wireless/chan.c    | 32 +++++++++++++++-----------------
 net/wireless/mesh.c    |  2 +-
 net/wireless/nl80211.c |  8 ++++----
 net/wireless/trace.h   |  2 +-
 7 files changed, 32 insertions(+), 34 deletions(-)

diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 6eb2420..54d4f67 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -438,13 +438,13 @@ bool cfg80211_chandef_usable(struct wiphy *wiphy,
 			     u32 prohibited_flags);
 
 /**
- * cfg80211_chandef_dfs_required - checks if radar detection is required
+ * cfg80211_chandef_dfs_check - checks if radar detection is required
  * @wiphy: the wiphy to validate against
  * @chandef: the channel definition to check
  * Return: 1 if radar detection is required, 0 if it is not, < 0 on error
  */
-int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
-				  const struct cfg80211_chan_def *chandef);
+int cfg80211_chandef_dfs_check(struct wiphy *wiphy,
+			       const struct cfg80211_chan_def *chandef);
 
 /**
  * ieee80211_chandef_rate_flags - returns rate flags for a channel
diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 06d2878..18dd2e2 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -281,8 +281,8 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		}
 	}
 
-	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
-					    &chandef);
+	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+					 &chandef);
 	if (err < 0) {
 		sdata_info(sdata,
 			   "Failed to join IBSS, invalid chandef\n");
@@ -774,8 +774,8 @@ static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 	/* if the current channel is a DFS channel, mark the channel as
 	 * unavailable.
 	 */
-	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
-					    &ifibss->chandef);
+	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+					 &ifibss->chandef);
 	if (err > 0)
 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 				     GFP_ATOMIC);
@@ -872,8 +872,8 @@ ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 		goto disconnect;
 	}
 
-	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
-					    &params.chandef);
+	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+					 &params.chandef);
 	if (err < 0)
 		goto disconnect;
 	if (err) {
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index f70e9cd..33cf125 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -902,8 +902,8 @@ ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 		return false;
 	}
 
-	err = cfg80211_chandef_dfs_required(sdata->local->hw.wiphy,
-					    &params.chandef);
+	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+					 &params.chandef);
 	if (err < 0)
 		return false;
 	if (err) {
diff --git a/net/wireless/chan.c b/net/wireless/chan.c
index 2cfff9e..aaf24fc 100644
--- a/net/wireless/chan.c
+++ b/net/wireless/chan.c
@@ -303,9 +303,9 @@ static u32 cfg80211_get_end_freq(u32 center_freq,
 	return end_freq;
 }
 
-static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
-					    u32 center_freq,
-					    u32 bandwidth)
+static int cfg80211_do_chandef_dfs_check(struct wiphy *wiphy,
+					 u32 center_freq,
+					 u32 bandwidth)
 {
 	struct ieee80211_channel *c;
 	u32 freq, start_freq, end_freq;
@@ -325,8 +325,8 @@ static int cfg80211_get_chans_dfs_required(struct wiphy *wiphy,
 }
 
 
-int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
-				  const struct cfg80211_chan_def *chandef)
+int cfg80211_chandef_dfs_check(struct wiphy *wiphy,
+			       const struct cfg80211_chan_def *chandef)
 {
 	int width;
 	int r;
@@ -335,21 +335,19 @@ int cfg80211_chandef_dfs_required(struct wiphy *wiphy,
 		return -EINVAL;
 
 	width = cfg80211_chandef_get_width(chandef);
-	if (width < 0)
-		return -EINVAL;
 
-	r = cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq1,
-					    width);
+	r = cfg80211_do_chandef_dfs_check(wiphy, chandef->center_freq1,
+					  width);
 	if (r)
 		return r;
 
 	if (!chandef->center_freq2)
 		return 0;
 
-	return cfg80211_get_chans_dfs_required(wiphy, chandef->center_freq2,
-					       width);
+	return cfg80211_do_chandef_dfs_check(wiphy, chandef->center_freq2,
+					     width);
 }
-EXPORT_SYMBOL(cfg80211_chandef_dfs_required);
+EXPORT_SYMBOL(cfg80211_chandef_dfs_check);
 
 static int cfg80211_get_chans_dfs_usable(struct wiphy *wiphy,
 					 u32 center_freq,
@@ -671,7 +669,7 @@ bool cfg80211_reg_can_beacon(struct wiphy *wiphy,
 
 	trace_cfg80211_reg_can_beacon(wiphy, chandef);
 
-	if (cfg80211_chandef_dfs_required(wiphy, chandef) > 0 &&
+	if (cfg80211_chandef_dfs_check(wiphy, chandef) > 0 &&
 	    cfg80211_chandef_dfs_available(wiphy, chandef)) {
 		/* We can skip IEEE80211_CHAN_NO_IR if chandef dfs available */
 		prohibited_flags = IEEE80211_CHAN_DISABLED;
@@ -743,8 +741,8 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chan = wdev->chandef.chan;
 			*chanmode = CHAN_MODE_SHARED;
 
-			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef) > 0)
+			if (cfg80211_chandef_dfs_check(wdev->wiphy,
+						       &wdev->chandef) > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
@@ -753,8 +751,8 @@ cfg80211_get_chan_state(struct wireless_dev *wdev,
 			*chan = wdev->chandef.chan;
 			*chanmode = CHAN_MODE_SHARED;
 
-			if (cfg80211_chandef_dfs_required(wdev->wiphy,
-							  &wdev->chandef) > 0)
+			if (cfg80211_chandef_dfs_check(wdev->wiphy,
+						       &wdev->chandef) > 0)
 				*radar_detect |= BIT(wdev->chandef.width);
 		}
 		return;
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
index 5af5cc6..d196a7c 100644
--- a/net/wireless/mesh.c
+++ b/net/wireless/mesh.c
@@ -178,7 +178,7 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 	if (!cfg80211_reg_can_beacon(&rdev->wiphy, &setup->chandef))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &setup->chandef);
+	err = cfg80211_chandef_dfs_check(wdev->wiphy, &setup->chandef);
 	if (err < 0)
 		return err;
 	if (err)
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index b6b2f6f..305ede8 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3261,7 +3261,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	if (!cfg80211_reg_can_beacon(&rdev->wiphy, &params.chandef))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &params.chandef);
+	err = cfg80211_chandef_dfs_check(wdev->wiphy, &params.chandef);
 	if (err < 0)
 		return err;
 	if (err) {
@@ -5796,7 +5796,7 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (wdev->cac_started)
 		return -EBUSY;
 
-	err = cfg80211_chandef_dfs_required(wdev->wiphy, &chandef);
+	err = cfg80211_chandef_dfs_check(wdev->wiphy, &chandef);
 	if (err < 0)
 		return err;
 
@@ -5936,8 +5936,8 @@ skip_beacons:
 	case NL80211_IFTYPE_P2P_GO:
 	case NL80211_IFTYPE_ADHOC:
 	case NL80211_IFTYPE_MESH_POINT:
-		err = cfg80211_chandef_dfs_required(wdev->wiphy,
-						    &params.chandef);
+		err = cfg80211_chandef_dfs_check(wdev->wiphy,
+						 &params.chandef);
 		if (err < 0)
 			return err;
 		if (err) {
diff --git a/net/wireless/trace.h b/net/wireless/trace.h
index aabccf1..80770f4 100644
--- a/net/wireless/trace.h
+++ b/net/wireless/trace.h
@@ -2207,7 +2207,7 @@ TRACE_EVENT(cfg80211_reg_can_beacon,
 		  WIPHY_PR_ARG, CHAN_DEF_PR_ARG)
 );
 
-TRACE_EVENT(cfg80211_chandef_dfs_required,
+TRACE_EVENT(cfg80211_chandef_dfs_check,
 	TP_PROTO(struct wiphy *wiphy, struct cfg80211_chan_def *chandef),
 	TP_ARGS(wiphy, chandef),
 	TP_STRUCT__entry(
-- 
1.9.0

[PATCH 3/3] cfg80211: change variable name

[Zhao, Gang]

Change "err" to "ret", since return value isn't zero doesn't always
mean error occured, sometimes it means success.

if (err)
        /* do things if function successfully returned */

looks strange to me, so change it.

Signed-off-by: Zhao, Gang <gamerh2o@gmail.com>
---
 net/mac80211/ibss.c    |  34 +++++++-------
 net/mac80211/mesh.c    |  14 +++---
 net/wireless/mesh.c    |  22 ++++-----
 net/wireless/nl80211.c | 118 ++++++++++++++++++++++++-------------------------
 4 files changed, 94 insertions(+), 94 deletions(-)

diff --git a/net/mac80211/ibss.c b/net/mac80211/ibss.c
index 18dd2e2..6c08424 100644
--- a/net/mac80211/ibss.c
+++ b/net/mac80211/ibss.c
@@ -229,7 +229,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	enum nl80211_bss_scan_width scan_width;
 	bool have_higher_than_11mbit;
 	bool radar_required = false;
-	int err;
+	int ret;
 
 	sdata_assert_lock(sdata);
 
@@ -281,14 +281,14 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		}
 	}
 
-	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+	ret = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
 					 &chandef);
-	if (err < 0) {
+	if (ret < 0) {
 		sdata_info(sdata,
 			   "Failed to join IBSS, invalid chandef\n");
 		return;
 	}
-	if (err > 0) {
+	if (ret > 0) {
 		if (!ifibss->userspace_handles_dfs) {
 			sdata_info(sdata,
 				   "Failed to join IBSS, DFS channel without control program\n");
@@ -359,8 +359,8 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 	sdata->vif.bss_conf.ibss_joined = true;
 	sdata->vif.bss_conf.ibss_creator = creator;
 
-	err = drv_join_ibss(local, sdata);
-	if (err) {
+	ret = drv_join_ibss(local, sdata);
+	if (ret) {
 		sdata->vif.bss_conf.ibss_joined = false;
 		sdata->vif.bss_conf.ibss_creator = false;
 		sdata->vif.bss_conf.enable_beacon = false;
@@ -371,7 +371,7 @@ static void __ieee80211_sta_join_ibss(struct ieee80211_sub_if_data *sdata,
 		ieee80211_vif_release_channel(sdata);
 		mutex_unlock(&local->mtx);
 		sdata_info(sdata, "Failed to join IBSS, driver failure: %d\n",
-			   err);
+			   ret);
 		return;
 	}
 
@@ -769,14 +769,14 @@ static void ieee80211_csa_connection_drop_work(struct work_struct *work)
 static void ieee80211_ibss_csa_mark_radar(struct ieee80211_sub_if_data *sdata)
 {
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
-	int err;
+	int ret;
 
 	/* if the current channel is a DFS channel, mark the channel as
 	 * unavailable.
 	 */
-	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+	ret = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
 					 &ifibss->chandef);
-	if (err > 0)
+	if (ret > 0)
 		cfg80211_radar_event(sdata->local->hw.wiphy, &ifibss->chandef,
 				     GFP_ATOMIC);
 }
@@ -790,7 +790,7 @@ ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_csa_ie csa_ie;
 	struct ieee80211_if_ibss *ifibss = &sdata->u.ibss;
 	enum nl80211_channel_type ch_type;
-	int err;
+	int ret;
 	u32 sta_flags;
 
 	sdata_assert_lock(sdata);
@@ -811,15 +811,15 @@ ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 
 	memset(&params, 0, sizeof(params));
 	memset(&csa_ie, 0, sizeof(csa_ie));
-	err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
+	ret = ieee80211_parse_ch_switch_ie(sdata, elems, beacon,
 					   ifibss->chandef.chan->band,
 					   sta_flags, ifibss->bssid, &csa_ie);
 	/* can't switch to destination channel, fail */
-	if (err < 0)
+	if (ret < 0)
 		goto disconnect;
 
 	/* did not contain a CSA */
-	if (err)
+	if (ret)
 		return false;
 
 	/* channel switch is not supported, disconnect */
@@ -872,11 +872,11 @@ ieee80211_ibss_process_chanswitch(struct ieee80211_sub_if_data *sdata,
 		goto disconnect;
 	}
 
-	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+	ret = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
 					 &params.chandef);
-	if (err < 0)
+	if (ret < 0)
 		goto disconnect;
-	if (err) {
+	if (ret) {
 		/* IBSS-DFS only allowed with a control program */
 		if (!ifibss->userspace_handles_dfs)
 			goto disconnect;
diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c
index 33cf125..336b963 100644
--- a/net/mac80211/mesh.c
+++ b/net/mac80211/mesh.c
@@ -861,7 +861,7 @@ ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 	struct ieee80211_csa_ie csa_ie;
 	struct ieee80211_if_mesh *ifmsh = &sdata->u.mesh;
 	enum ieee80211_band band = ieee80211_get_sdata_band(sdata);
-	int err;
+	int ret;
 	u32 sta_flags;
 
 	sdata_assert_lock(sdata);
@@ -879,12 +879,12 @@ ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 
 	memset(&params, 0, sizeof(params));
 	memset(&csa_ie, 0, sizeof(csa_ie));
-	err = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band,
+	ret = ieee80211_parse_ch_switch_ie(sdata, elems, beacon, band,
 					   sta_flags, sdata->vif.addr,
 					   &csa_ie);
-	if (err < 0)
+	if (ret < 0)
 		return false;
-	if (err)
+	if (ret)
 		return false;
 
 	params.chandef = csa_ie.chandef;
@@ -902,11 +902,11 @@ ieee80211_mesh_process_chnswitch(struct ieee80211_sub_if_data *sdata,
 		return false;
 	}
 
-	err = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
+	ret = cfg80211_chandef_dfs_check(sdata->local->hw.wiphy,
 					 &params.chandef);
-	if (err < 0)
+	if (ret < 0)
 		return false;
-	if (err) {
+	if (ret) {
 		params.radar_required = true;
 		/* TODO: DFS not (yet) supported */
 		return false;
diff --git a/net/wireless/mesh.c b/net/wireless/mesh.c
index d196a7c..1e74e5d 100644
--- a/net/wireless/mesh.c
+++ b/net/wireless/mesh.c
@@ -100,7 +100,7 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 {
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	u8 radar_detect_width = 0;
-	int err;
+	int ret;
 
 	BUILD_BUG_ON(IEEE80211_MAX_SSID_LEN != IEEE80211_MAX_MESH_ID_LEN);
 
@@ -178,27 +178,27 @@ int __cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
 	if (!cfg80211_reg_can_beacon(&rdev->wiphy, &setup->chandef))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_check(wdev->wiphy, &setup->chandef);
-	if (err < 0)
-		return err;
-	if (err)
+	ret = cfg80211_chandef_dfs_check(wdev->wiphy, &setup->chandef);
+	if (ret < 0)
+		return ret;
+	if (ret)
 		radar_detect_width = BIT(setup->chandef.width);
 
-	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
+	ret = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
 					   setup->chandef.chan,
 					   CHAN_MODE_SHARED,
 					   radar_detect_width);
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
-	err = rdev_join_mesh(rdev, dev, conf, setup);
-	if (!err) {
+	ret = rdev_join_mesh(rdev, dev, conf, setup);
+	if (!ret) {
 		memcpy(wdev->ssid, setup->mesh_id, setup->mesh_id_len);
 		wdev->mesh_id_len = setup->mesh_id_len;
 		wdev->chandef = setup->chandef;
 	}
 
-	return err;
+	return ret;
 }
 
 int cfg80211_join_mesh(struct cfg80211_registered_device *rdev,
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 305ede8..eca64cd 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -3141,7 +3141,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	struct net_device *dev = info->user_ptr[1];
 	struct wireless_dev *wdev = dev->ieee80211_ptr;
 	struct cfg80211_ap_settings params;
-	int err;
+	int ret;
 	u8 radar_detect_width = 0;
 
 	if (dev->ieee80211_ptr->iftype != NL80211_IFTYPE_AP &&
@@ -3162,18 +3162,18 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	    !info->attrs[NL80211_ATTR_BEACON_HEAD])
 		return -EINVAL;
 
-	err = nl80211_parse_beacon(info->attrs, &params.beacon);
-	if (err)
-		return err;
+	ret = nl80211_parse_beacon(info->attrs, &params.beacon);
+	if (ret)
+		return ret;
 
 	params.beacon_interval =
 		nla_get_u32(info->attrs[NL80211_ATTR_BEACON_INTERVAL]);
 	params.dtim_period =
 		nla_get_u32(info->attrs[NL80211_ATTR_DTIM_PERIOD]);
 
-	err = cfg80211_validate_beacon_int(rdev, params.beacon_interval);
-	if (err)
-		return err;
+	ret = cfg80211_validate_beacon_int(rdev, params.beacon_interval);
+	if (ret)
+		return ret;
 
 	/*
 	 * In theory, some of these attributes should be required here
@@ -3211,10 +3211,10 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	} else
 		params.auth_type = NL80211_AUTHTYPE_AUTOMATIC;
 
-	err = nl80211_crypto_settings(rdev, info, &params.crypto,
+	ret = nl80211_crypto_settings(rdev, info, &params.crypto,
 				      NL80211_MAX_NR_CIPHER_SUITES);
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
 	if (info->attrs[NL80211_ATTR_INACTIVITY_TIMEOUT]) {
 		if (!(rdev->wiphy.features & NL80211_FEATURE_INACTIVITY_TIMER))
@@ -3250,9 +3250,9 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	if (info->attrs[NL80211_ATTR_WIPHY_FREQ]) {
-		err = nl80211_parse_chandef(rdev, info, &params.chandef);
-		if (err)
-			return err;
+		ret = nl80211_parse_chandef(rdev, info, &params.chandef);
+		if (ret)
+			return ret;
 	} else if (wdev->preset_chandef.chan) {
 		params.chandef = wdev->preset_chandef;
 	} else if (!nl80211_get_ap_channel(rdev, &params))
@@ -3261,20 +3261,20 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	if (!cfg80211_reg_can_beacon(&rdev->wiphy, &params.chandef))
 		return -EINVAL;
 
-	err = cfg80211_chandef_dfs_check(wdev->wiphy, &params.chandef);
-	if (err < 0)
-		return err;
-	if (err) {
+	ret = cfg80211_chandef_dfs_check(wdev->wiphy, &params.chandef);
+	if (ret < 0)
+		return ret;
+	if (ret) {
 		radar_detect_width = BIT(params.chandef.width);
 		params.radar_required = true;
 	}
 
-	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
+	ret = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
 					   params.chandef.chan,
 					   CHAN_MODE_SHARED,
 					   radar_detect_width);
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
 	if (info->attrs[NL80211_ATTR_ACL_POLICY]) {
 		params.acl = parse_acl_data(&rdev->wiphy, info);
@@ -3283,8 +3283,8 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 	}
 
 	wdev_lock(wdev);
-	err = rdev_start_ap(rdev, dev, &params);
-	if (!err) {
+	ret = rdev_start_ap(rdev, dev, &params);
+	if (!ret) {
 		wdev->preset_chandef = params.chandef;
 		wdev->beacon_interval = params.beacon_interval;
 		wdev->chandef = params.chandef;
@@ -3295,7 +3295,7 @@ static int nl80211_start_ap(struct sk_buff *skb, struct genl_info *info)
 
 	kfree(params.acl);
 
-	return err;
+	return ret;
 }
 
 static int nl80211_set_beacon(struct sk_buff *skb, struct genl_info *info)
@@ -5780,15 +5780,15 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	struct cfg80211_chan_def chandef;
 	enum nl80211_dfs_regions dfs_region;
 	unsigned int cac_time_ms;
-	int err;
+	int ret;
 
 	dfs_region = reg_get_dfs_region(wdev->wiphy);
 	if (dfs_region == NL80211_DFS_UNSET)
 		return -EINVAL;
 
-	err = nl80211_parse_chandef(rdev, info, &chandef);
-	if (err)
-		return err;
+	ret = nl80211_parse_chandef(rdev, info, &chandef);
+	if (ret)
+		return ret;
 
 	if (netif_carrier_ok(dev))
 		return -EBUSY;
@@ -5796,11 +5796,11 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (wdev->cac_started)
 		return -EBUSY;
 
-	err = cfg80211_chandef_dfs_check(wdev->wiphy, &chandef);
-	if (err < 0)
-		return err;
+	ret = cfg80211_chandef_dfs_check(wdev->wiphy, &chandef);
+	if (ret < 0)
+		return ret;
 
-	if (err == 0)
+	if (ret == 0)
 		return -EINVAL;
 
 	if (!cfg80211_chandef_dfs_usable(wdev->wiphy, &chandef))
@@ -5809,25 +5809,25 @@ static int nl80211_start_radar_detection(struct sk_buff *skb,
 	if (!rdev->ops->start_radar_detection)
 		return -EOPNOTSUPP;
 
-	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
+	ret = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
 					   chandef.chan, CHAN_MODE_SHARED,
 					   BIT(chandef.width));
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
 	cac_time_ms = cfg80211_chandef_dfs_cac_time(&rdev->wiphy, &chandef);
 	if (WARN_ON(!cac_time_ms))
 		cac_time_ms = IEEE80211_DFS_MIN_CAC_TIME_MS;
 
-	err = rdev->ops->start_radar_detection(&rdev->wiphy, dev, &chandef,
+	ret = rdev->ops->start_radar_detection(&rdev->wiphy, dev, &chandef,
 					       cac_time_ms);
-	if (!err) {
+	if (!ret) {
 		wdev->chandef = chandef;
 		wdev->cac_started = true;
 		wdev->cac_start_time = jiffies;
 		wdev->cac_time_ms = cac_time_ms;
 	}
-	return err;
+	return ret;
 }
 
 static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
@@ -5841,7 +5841,7 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	 */
 	static struct nlattr *csa_attrs[NL80211_ATTR_MAX+1];
 	u8 radar_detect_width = 0;
-	int err;
+	int ret;
 	bool need_new_beacon = false;
 
 	if (!rdev->ops->channel_switch ||
@@ -5884,19 +5884,19 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	if (!need_new_beacon)
 		goto skip_beacons;
 
-	err = nl80211_parse_beacon(info->attrs, &params.beacon_after);
-	if (err)
-		return err;
+	ret = nl80211_parse_beacon(info->attrs, &params.beacon_after);
+	if (ret)
+		return ret;
 
-	err = nla_parse_nested(csa_attrs, NL80211_ATTR_MAX,
+	ret = nla_parse_nested(csa_attrs, NL80211_ATTR_MAX,
 			       info->attrs[NL80211_ATTR_CSA_IES],
 			       nl80211_policy);
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
-	err = nl80211_parse_beacon(csa_attrs, &params.beacon_csa);
-	if (err)
-		return err;
+	ret = nl80211_parse_beacon(csa_attrs, &params.beacon_csa);
+	if (ret)
+		return ret;
 
 	if (!csa_attrs[NL80211_ATTR_CSA_C_OFF_BEACON])
 		return -EINVAL;
@@ -5924,9 +5924,9 @@ static int nl80211_channel_switch(struct sk_buff *skb, struct genl_info *info)
 	}
 
 skip_beacons:
-	err = nl80211_parse_chandef(rdev, info, &params.chandef);
-	if (err)
-		return err;
+	ret = nl80211_parse_chandef(rdev, info, &params.chandef);
+	if (ret)
+		return ret;
 
 	if (!cfg80211_reg_can_beacon(&rdev->wiphy, &params.chandef))
 		return -EINVAL;
@@ -5936,11 +5936,11 @@ skip_beacons:
 	case NL80211_IFTYPE_P2P_GO:
 	case NL80211_IFTYPE_ADHOC:
 	case NL80211_IFTYPE_MESH_POINT:
-		err = cfg80211_chandef_dfs_check(wdev->wiphy,
+		ret = cfg80211_chandef_dfs_check(wdev->wiphy,
 						 &params.chandef);
-		if (err < 0)
-			return err;
-		if (err) {
+		if (ret < 0)
+			return ret;
+		if (ret) {
 			radar_detect_width = BIT(params.chandef.width);
 			params.radar_required = true;
 		}
@@ -5949,21 +5949,21 @@ skip_beacons:
 		break;
 	}
 
-	err = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
+	ret = cfg80211_can_use_iftype_chan(rdev, wdev, wdev->iftype,
 					   params.chandef.chan,
 					   CHAN_MODE_SHARED,
 					   radar_detect_width);
-	if (err)
-		return err;
+	if (ret)
+		return ret;
 
 	if (info->attrs[NL80211_ATTR_CH_SWITCH_BLOCK_TX])
 		params.block_tx = true;
 
 	wdev_lock(wdev);
-	err = rdev_channel_switch(rdev, dev, &params);
+	ret = rdev_channel_switch(rdev, dev, &params);
 	wdev_unlock(wdev);
 
-	return err;
+	return ret;
 }
 
 static int nl80211_send_bss(struct sk_buff *msg, struct netlink_callback *cb,
-- 
1.9.0

Re: [PATCH 0/3] fix and improvements

[Zhao, Gang]

On Sun, 2014-04-20 at 00:32:36 +0800, Zhao, Gang wrote:
> I think the first patch should also be applied to 3.15.
>
> Zhao, Gang (3):
>   cfg80211: fix incorrect checking of return value
>   cfg80211/mac80211: rename cfg80211_chandef_dfs_required()
>   cfg80211: change variable name
>
I found that the incorrect checking of return value problem had already
been fixed in mac80211-next 2beb6dab2d79 ("cfg80211/mac80211: refactor
cfg80211_chandef_dfs_required()"). But not on mac80211 tree.

I think the fix may worth going to mac80211 and also
stable-3.14. Johannes, you can decide whether to apply this patch or it
needs to be modified, since if it's applied, it will surely cause
conflict in future time.

The following two improvement patches should be ignored, since I found
they need to be rebased to be applied on mac80211-next.

Re: [PATCH 0/3] fix and improvements

[Johannes Berg]

On Sun, 2014-04-20 at 11:39 +0800, Zhao, Gang wrote:

> I found that the incorrect checking of return value problem had already
> been fixed in mac80211-next 2beb6dab2d79 ("cfg80211/mac80211: refactor
> cfg80211_chandef_dfs_required()"). But not on mac80211 tree.
> 
> I think the fix may worth going to mac80211 and also
> stable-3.14. Johannes, you can decide whether to apply this patch or it
> needs to be modified, since if it's applied, it will surely cause
> conflict in future time.

I'll let the DFS folk worry about that, I don't use that myself ... if
they need it then they might find the issue or whatever. Chances are,
since CSA isn't there, they won't care much.

> The following two improvement patches should be ignored, since I found
> they need to be rebased to be applied on mac80211-next.

OK.

johannes