nl80211: clean up CQM settings code

Clean up the CQM settings code a bit and while at it
enforce that when setting the threshold to 0 (disable)
the hysteresis is also set to 0 to avoid confusion.
As we haven't enforce it, simply override userspace.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>

1 files changed, 24 insertions, 27 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index f7cb12178bd2..c2a40a2e56bd 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -7562,14 +7562,12 @@ static int nl80211_set_cqm_txe(struct genl_info *info,
                                u32 rate, u32 pkts, u32 intvl)
 {
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
-        struct wireless_dev *wdev;
         struct net_device *dev = info->user_ptr[1];
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
 
         if (rate > 100 || intvl > NL80211_CQM_TXE_MAX_INTVL)
                 return -EINVAL;
 
-        wdev = dev->ieee80211_ptr;
-
         if (!rdev->ops->set_cqm_txe_config)
                 return -EOPNOTSUPP;
 
@@ -7584,13 +7582,15 @@ static int nl80211_set_cqm_rssi(struct genl_info *info,
                                 s32 threshold, u32 hysteresis)
 {
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
-        struct wireless_dev *wdev;
         struct net_device *dev = info->user_ptr[1];
+        struct wireless_dev *wdev = dev->ieee80211_ptr;
 
         if (threshold > 0)
                 return -EINVAL;
 
-        wdev = dev->ieee80211_ptr;
+        /* disabling - hysteresis should also be zero then */
+        if (threshold == 0)
+                hysteresis = 0;
 
         if (!rdev->ops->set_cqm_rssi_config)
                 return -EOPNOTSUPP;
@@ -7609,36 +7609,33 @@ static int nl80211_set_cqm(struct sk_buff *skb, struct genl_info *info)
         int err;
 
         cqm = info->attrs[NL80211_ATTR_CQM];
-        if (!cqm) {
-                err = -EINVAL;
-                goto out;
-        }
+        if (!cqm)
+                return -EINVAL;
 
         err = nla_parse_nested(attrs, NL80211_ATTR_CQM_MAX, cqm,
                                nl80211_attr_cqm_policy);
         if (err)
-                goto out;
+                return err;
 
         if (attrs[NL80211_ATTR_CQM_RSSI_THOLD] &&
             attrs[NL80211_ATTR_CQM_RSSI_HYST]) {
-                s32 threshold;
-                u32 hysteresis;
-                threshold = nla_get_u32(attrs[NL80211_ATTR_CQM_RSSI_THOLD]);
-                hysteresis = nla_get_u32(attrs[NL80211_ATTR_CQM_RSSI_HYST]);
-                err = nl80211_set_cqm_rssi(info, threshold, hysteresis);
-        } else if (attrs[NL80211_ATTR_CQM_TXE_RATE] &&
-                   attrs[NL80211_ATTR_CQM_TXE_PKTS] &&
-                   attrs[NL80211_ATTR_CQM_TXE_INTVL]) {
-                u32 rate, pkts, intvl;
-                rate = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_RATE]);
-                pkts = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_PKTS]);
-                intvl = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_INTVL]);
-                err = nl80211_set_cqm_txe(info, rate, pkts, intvl);
-        } else
-                err = -EINVAL;
+                s32 threshold = nla_get_s32(attrs[NL80211_ATTR_CQM_RSSI_THOLD]);
+                u32 hysteresis = nla_get_u32(attrs[NL80211_ATTR_CQM_RSSI_HYST]);
 
-out:
-        return err;
+                return nl80211_set_cqm_rssi(info, threshold, hysteresis);
+        }
+
+        if (attrs[NL80211_ATTR_CQM_TXE_RATE] &&
+            attrs[NL80211_ATTR_CQM_TXE_PKTS] &&
+            attrs[NL80211_ATTR_CQM_TXE_INTVL]) {
+                u32 rate = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_RATE]);
+                u32 pkts = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_PKTS]);
+                u32 intvl = nla_get_u32(attrs[NL80211_ATTR_CQM_TXE_INTVL]);
+
+                return nl80211_set_cqm_txe(info, rate, pkts, intvl);
+        }
+
+        return -EINVAL;
 }
 
 static int nl80211_join_mesh(struct sk_buff *skb, struct genl_info *info)