nl80211: Allow set network namespace by fd

Added new NL80211_ATTR_NETNS_FD which allows to
set namespace via nl80211 by fd.

Signed-off-by: Vadim Kochan <vadim4j@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>

3 files changed, 14 insertions, 5 deletions

diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index f52797a90816..f68532b015db 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -2098,6 +2098,8 @@ enum nl80211_attrs {
 
         NL80211_ATTR_SURVEY_RADIO_STATS,
 
+        NL80211_ATTR_NETNS_FD,
+
         /* add attributes here, update the policy in nl80211.c */
 
         __NL80211_ATTR_AFTER_LAST,
diff --git a/net/core/net_namespace.c b/net/core/net_namespace.c
index 7f155175bba8..5d5ee8f3e4ff 100644
--- a/net/core/net_namespace.c
+++ b/net/core/net_namespace.c
@@ -361,6 +361,7 @@ struct net *get_net_ns_by_fd(int fd)
         return ERR_PTR(-EINVAL);
 }
 #endif
+EXPORT_SYMBOL_GPL(get_net_ns_by_fd);
 
 struct net *get_net_ns_by_pid(pid_t pid)
 {
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index c5661c5ad8f3..c64100ec79e3 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -397,6 +397,7 @@ static const struct nla_policy nl80211_policy[NUM_NL80211_ATTR] = {
         [NL80211_ATTR_SMPS_MODE] = { .type = NLA_U8 },
         [NL80211_ATTR_MAC_MASK] = { .len = ETH_ALEN },
         [NL80211_ATTR_WIPHY_SELF_MANAGED_REG] = { .type = NLA_FLAG },
+        [NL80211_ATTR_NETNS_FD] = { .type = NLA_U32 },
 };
 
 /* policy for the key attributes */
@@ -7762,14 +7763,19 @@ static int nl80211_wiphy_netns(struct sk_buff *skb, struct genl_info *info)
         struct cfg80211_registered_device *rdev = info->user_ptr[0];
         struct net *net;
         int err;
-        u32 pid;
 
-        if (!info->attrs[NL80211_ATTR_PID])
-                return -EINVAL;
+        if (info->attrs[NL80211_ATTR_PID]) {
+                u32 pid = nla_get_u32(info->attrs[NL80211_ATTR_PID]);
+
+                net = get_net_ns_by_pid(pid);
+        } else if (info->attrs[NL80211_ATTR_NETNS_FD]) {
+                u32 fd = nla_get_u32(info->attrs[NL80211_ATTR_NETNS_FD]);
 
-        pid = nla_get_u32(info->attrs[NL80211_ATTR_PID]);
+                net = get_net_ns_by_fd(fd);
+        } else {
+                return -EINVAL;
+        }
 
-        net = get_net_ns_by_pid(pid);
         if (IS_ERR(net))
                 return PTR_ERR(net);