From 78f22b6a3a9254460d23060530b48ae02a9394e3 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 24 Mar 2014 17:57:27 +0100 Subject: cfg80211: allow userspace to take ownership of interfaces When dynamically creating interfaces from userspace, e.g. for P2P usage, such interfaces are usually owned by the process that created them, i.e. wpa_supplicant. Should wpa_supplicant crash, such interfaces will often cease operating properly and cause problems on restarting the process. To avoid this problem, introduce an ownership concept for interfaces. If an interface is owned by a netlink socket, then it will be destroyed if the netlink socket is closed for any reason, including if the process it belongs to crashed. This gives us a race-free way to get rid of any such interfaces. Signed-off-by: Johannes Berg --- include/net/cfg80211.h | 3 +++ include/uapi/linux/nl80211.h | 6 ++++++ 2 files changed, 9 insertions(+) (limited to 'include') diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h index f3539a15c411..6510ccf53a54 100644 --- a/include/net/cfg80211.h +++ b/include/net/cfg80211.h @@ -3194,6 +3194,7 @@ struct cfg80211_cached_keys; * @ibss_dfs_possible: (private) IBSS may change to a DFS channel * @event_list: (private) list for internal event processing * @event_lock: (private) lock for event list + * @owner_nlportid: (private) owner socket port ID */ struct wireless_dev { struct wiphy *wiphy; @@ -3241,6 +3242,8 @@ struct wireless_dev { unsigned long cac_start_time; unsigned int cac_time_ms; + u32 owner_nlportid; + #ifdef CONFIG_CFG80211_WEXT /* wext data */ struct { diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h index 1ba9d626aa83..5e405fd55a71 100644 --- a/include/uapi/linux/nl80211.h +++ b/include/uapi/linux/nl80211.h @@ -1579,6 +1579,10 @@ enum nl80211_commands { * @NL80211_ATTR_TDLS_PEER_CAPABILITY: flags for TDLS peer capabilities, u32. * As specified in the &enum nl80211_tdls_peer_capability. * + * @NL80211_ATTR_IFACE_SOCKET_OWNER: flag attribute, if set during interface + * creation then the new interface will be owned by the netlink socket + * that created it and will be destroyed when the socket is closed + * * @NL80211_ATTR_MAX: highest attribute number currently defined * @__NL80211_ATTR_AFTER_LAST: internal use */ @@ -1914,6 +1918,8 @@ enum nl80211_attrs { NL80211_ATTR_TDLS_PEER_CAPABILITY, + NL80211_ATTR_IFACE_SOCKET_OWNER, + /* add attributes here, update the policy in nl80211.c */ __NL80211_ATTR_AFTER_LAST, -- cgit v1.2.3