nl80211: make get_vlan logic more common

get_vlan() sets the output parameter even if it
returns an error, which is a bit odd. Instead,
convert it to use ERR_PTR.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 31 insertions, 23 deletions

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index 9755b3f04dd7..889f06483862 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2485,26 +2485,34 @@ static int nl80211_get_station(struct sk_buff *skb, struct genl_info *info)
 /*
  * Get vlan interface making sure it is running and on the right wiphy.
  */
-static int get_vlan(struct genl_info *info,
-                    struct cfg80211_registered_device *rdev,
-                    struct net_device **vlan)
+static struct net_device *get_vlan(struct genl_info *info,
+                                   struct cfg80211_registered_device *rdev)
 {
         struct nlattr *vlanattr = info->attrs[NL80211_ATTR_STA_VLAN];
-        *vlan = NULL;
-
-        if (vlanattr) {
-                *vlan = dev_get_by_index(genl_info_net(info),
-                                         nla_get_u32(vlanattr));
-                if (!*vlan)
-                        return -ENODEV;
-                if (!(*vlan)->ieee80211_ptr)
-                        return -EINVAL;
-                if ((*vlan)->ieee80211_ptr->wiphy != &rdev->wiphy)
-                        return -EINVAL;
-                if (!netif_running(*vlan))
-                        return -ENETDOWN;
+        struct net_device *v;
+        int ret;
+
+        if (!vlanattr)
+                return NULL;
+
+        v = dev_get_by_index(genl_info_net(info), nla_get_u32(vlanattr));
+        if (!v)
+                return ERR_PTR(-ENODEV);
+
+        if (!v->ieee80211_ptr || v->ieee80211_ptr->wiphy != &rdev->wiphy) {
+                ret = -EINVAL;
+                goto error;
         }
-        return 0;
+
+        if (!netif_running(v)) {
+                ret = -ENETDOWN;
+                goto error;
+        }
+
+        return v;
+ error:
+        dev_put(v);
+        return ERR_PTR(ret);
 }
 
 static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info)
@@ -2554,9 +2562,9 @@ static int nl80211_set_station(struct sk_buff *skb, struct genl_info *info)
                 params.plink_state =
                     nla_get_u8(info->attrs[NL80211_ATTR_STA_PLINK_STATE]);
 
-        err = get_vlan(info, rdev, &params.vlan);
-        if (err)
-                goto out;
+        params.vlan = get_vlan(info, rdev);
+        if (IS_ERR(params.vlan))
+                return PTR_ERR(params.vlan);
 
         /* validate settings */
         err = 0;
@@ -2724,9 +2732,9 @@ static int nl80211_new_station(struct sk_buff *skb, struct genl_info *info)
               (rdev->wiphy.flags & WIPHY_FLAG_TDLS_EXTERNAL_SETUP)))
                 return -EINVAL;
 
-        err = get_vlan(info, rdev, &params.vlan);
-        if (err)
-                goto out;
+        params.vlan = get_vlan(info, rdev);
+        if (IS_ERR(params.vlan))
+                return PTR_ERR(params.vlan);
 
         /* validate settings */
         err = 0;