From 896ff0635a312022c91e2bef30c80abc27af62e8 Mon Sep 17 00:00:00 2001 From: Denis Kenzior Date: Wed, 3 Aug 2016 16:58:33 -0500 Subject: [PATCH] cfg80211: always notify userspace of new wireless netdevs This change alters the semantics of NL80211_CMD_NEW_INTERFACE events by always sending this event whenever a new net_device object associated with a wdev is registered. Prior to this change, this event was only sent as a result of NL80211_CMD_NEW_INTERFACE command sent from userspace. This allows userspace to reliably detect new wireless interfaces (e.g. due to hardware hot-plug events, etc). For wdevs created without an associated net_device object (e.g. NL80211_IFTYPE_P2P_DEVICE), the NL80211_CMD_NEW_INTERFACE event is still generated inside the relevant nl80211 command handler. Signed-off-by: Denis Kenzior Signed-off-by: Johannes Berg --- net/wireless/core.c | 2 ++ net/wireless/nl80211.c | 46 ++++++++++++++++++++++++++++++++-------------- net/wireless/nl80211.h | 3 +++ 3 files changed, 37 insertions(+), 14 deletions(-) diff --git a/net/wireless/core.c b/net/wireless/core.c index 7645e97..7758c0f 100644 --- a/net/wireless/core.c +++ b/net/wireless/core.c @@ -1079,6 +1079,8 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb, wdev->iftype == NL80211_IFTYPE_P2P_CLIENT || wdev->iftype == NL80211_IFTYPE_ADHOC) && !wdev->use_4addr) dev->priv_flags |= IFF_DONT_BRIDGE; + + nl80211_notify_iface(rdev, wdev, NL80211_CMD_NEW_INTERFACE); break; case NETDEV_GOING_DOWN: cfg80211_leave(rdev, wdev); diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c index f02653a..a8c062d 100644 --- a/net/wireless/nl80211.c +++ b/net/wireless/nl80211.c @@ -2751,7 +2751,7 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info) struct cfg80211_registered_device *rdev = info->user_ptr[0]; struct vif_params params; struct wireless_dev *wdev; - struct sk_buff *msg, *event; + struct sk_buff *msg; int err; enum nl80211_iftype type = NL80211_IFTYPE_UNSPECIFIED; u32 flags; @@ -2855,20 +2855,15 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info) return -ENOBUFS; } - event = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); - if (event) { - if (nl80211_send_iface(event, 0, 0, 0, - rdev, wdev, false) < 0) { - nlmsg_free(event); - goto out; - } - - genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), - event, 0, NL80211_MCGRP_CONFIG, - GFP_KERNEL); - } + /* + * For wdevs which have no associated netdev object (e.g. of type + * NL80211_IFTYPE_P2P_DEVICE), emit the NEW_INTERFACE event here. + * For all other types, the event will be generated from the + * netdev notifier + */ + if (!wdev->netdev) + nl80211_notify_iface(rdev, wdev, NL80211_CMD_NEW_INTERFACE); -out: return genlmsg_reply(msg, info); } @@ -11847,6 +11842,29 @@ void nl80211_notify_wiphy(struct cfg80211_registered_device *rdev, NL80211_MCGRP_CONFIG, GFP_KERNEL); } +void nl80211_notify_iface(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + enum nl80211_commands cmd) +{ + struct sk_buff *msg; + + WARN_ON(cmd != NL80211_CMD_NEW_INTERFACE && + cmd != NL80211_CMD_DEL_INTERFACE); + + msg = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL); + if (!msg) + return; + + if (nl80211_send_iface(msg, 0, 0, 0, rdev, wdev, + cmd == NL80211_CMD_DEL_INTERFACE) < 0) { + nlmsg_free(msg); + return; + } + + genlmsg_multicast_netns(&nl80211_fam, wiphy_net(&rdev->wiphy), msg, 0, + NL80211_MCGRP_CONFIG, GFP_KERNEL); +} + static int nl80211_add_scan_req(struct sk_buff *msg, struct cfg80211_registered_device *rdev) { diff --git a/net/wireless/nl80211.h b/net/wireless/nl80211.h index a63f402..7e3821d 100644 --- a/net/wireless/nl80211.h +++ b/net/wireless/nl80211.h @@ -7,6 +7,9 @@ int nl80211_init(void); void nl80211_exit(void); void nl80211_notify_wiphy(struct cfg80211_registered_device *rdev, enum nl80211_commands cmd); +void nl80211_notify_iface(struct cfg80211_registered_device *rdev, + struct wireless_dev *wdev, + enum nl80211_commands cmd); void nl80211_send_scan_start(struct cfg80211_registered_device *rdev, struct wireless_dev *wdev); struct sk_buff *nl80211_build_scan_msg(struct cfg80211_registered_device *rdev, -- 2.7.4