Hi,
v4:
- rtnl locking issues fixed in patch 2
v3:
- backward compatibility define tweaked in patch 1
- added missing signed-off-by:
v2:
- split the patch
- In patch 1, use a generic NL80211_ATTR_SOCKET_OWNER attribute and
convert the old code that uses NL80211_ATTR_IFACE_SOCKET_OWNER to
use the new value. A define is provided for backward compatibility.
- Any pending schedule scan stop worker is cancelled when interface is
taken down in patch 2
Cheers,
Jukka
Jukka Rissanen (2):
nl80211: Replace interface socket owner attribute with more generic
one
nl80211: Stop scheduled scan if netlink client disappears
include/net/cfg80211.h | 2 ++
include/uapi/linux/nl80211.h | 10 +++++++---
net/wireless/core.c | 5 ++++-
net/wireless/nl80211.c | 39 +++++++++++++++++++++++++++++++++++++--
4 files changed, 50 insertions(+), 6 deletions(-)
--
1.8.3.1
On Thu, 2014-11-13 at 15:49 +0200, Jukka Rissanen wrote:
> An attribute NL80211_ATTR_SOCKET_OWNER can be set by the scan initiator.
> If present, the attribute will cause the scan to be stopped if the client
> dies.
> + if (rtnl_trylock()) {
> + __cfg80211_stop_sched_scan(rdev, false);
> + rtnl_unlock();
> + }
Umm, no. Locking in the kernel doesn't work this way.
johannes
Replace NL80211_ATTR_IFACE_SOCKET_OWNER attribute with more generic
NL80211_ATTR_SOCKET_OWNER that can be used with other commands
that interface creation.
Signed-off-by: Jukka Rissanen <[email protected]>
---
include/uapi/linux/nl80211.h | 7 ++++---
net/wireless/nl80211.c | 4 ++--
2 files changed, 6 insertions(+), 5 deletions(-)
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 442369f..185f9c7 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1637,9 +1637,9 @@ 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
+ * @NL80211_ATTR_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
+ * that created it and will be destroyed when the socket is closed.
*
* @NL80211_ATTR_TDLS_INITIATOR: flag attribute indicating the current end is
* the TDLS link initiator.
@@ -2004,7 +2004,7 @@ enum nl80211_attrs {
NL80211_ATTR_TDLS_PEER_CAPABILITY,
- NL80211_ATTR_IFACE_SOCKET_OWNER,
+ NL80211_ATTR_SOCKET_OWNER,
NL80211_ATTR_CSA_C_OFFSETS_TX,
NL80211_ATTR_MAX_CSA_COUNTERS,
@@ -2030,6 +2030,7 @@ enum nl80211_attrs {
/* source-level API compatibility */
#define NL80211_ATTR_SCAN_GENERATION NL80211_ATTR_GENERATION
#define NL80211_ATTR_MESH_PARAMS NL80211_ATTR_MESH_CONFIG
+#define NL80211_ATTR_IFACE_SOCKET_OWNER NL80211_ATTR_SOCKET_OWNER
/*
* Allow user space programs to use #ifdef on new attributes by defining them
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index d0a8361..df447c0 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -388,7 +388,7 @@ static const struct nla_policy nl80211_policy[NL80211_ATTR_MAX+1] = {
[NL80211_ATTR_MAC_HINT] = { .len = ETH_ALEN },
[NL80211_ATTR_WIPHY_FREQ_HINT] = { .type = NLA_U32 },
[NL80211_ATTR_TDLS_PEER_CAPABILITY] = { .type = NLA_U32 },
- [NL80211_ATTR_IFACE_SOCKET_OWNER] = { .type = NLA_FLAG },
+ [NL80211_ATTR_SOCKET_OWNER] = { .type = NLA_FLAG },
[NL80211_ATTR_CSA_C_OFFSETS_TX] = { .type = NLA_BINARY },
[NL80211_ATTR_USE_RRM] = { .type = NLA_FLAG },
[NL80211_ATTR_TSID] = { .type = NLA_U8 },
@@ -2646,7 +2646,7 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
return PTR_ERR(wdev);
}
- if (info->attrs[NL80211_ATTR_IFACE_SOCKET_OWNER])
+ if (info->attrs[NL80211_ATTR_SOCKET_OWNER])
wdev->owner_nlportid = info->snd_portid;
switch (type) {
--
1.8.3.1
An attribute NL80211_ATTR_SOCKET_OWNER can be set by the scan initiator.
If present, the attribute will cause the scan to be stopped if the client
dies.
Signed-off-by: Jukka Rissanen <[email protected]>
---
include/net/cfg80211.h | 2 ++
include/uapi/linux/nl80211.h | 3 +++
net/wireless/core.c | 5 ++++-
net/wireless/nl80211.c | 35 +++++++++++++++++++++++++++++++++++
4 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/include/net/cfg80211.h b/include/net/cfg80211.h
index 220d5f5..84378bf 100644
--- a/include/net/cfg80211.h
+++ b/include/net/cfg80211.h
@@ -1512,6 +1512,8 @@ struct cfg80211_sched_scan_request {
struct wiphy *wiphy;
struct net_device *dev;
unsigned long scan_start;
+ u32 owner_nlportid;
+ struct work_struct sched_scan_stop_wk;
/* keep last */
struct ieee80211_channel *channels[0];
diff --git a/include/uapi/linux/nl80211.h b/include/uapi/linux/nl80211.h
index 185f9c7..5038240 100644
--- a/include/uapi/linux/nl80211.h
+++ b/include/uapi/linux/nl80211.h
@@ -1640,6 +1640,9 @@ enum nl80211_commands {
* @NL80211_ATTR_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.
+ * If set during scheduled scan start then the new scan req will be
+ * owned by the netlink socket that created it and the scheduled scan will
+ * be stopped when the socket is closed.
*
* @NL80211_ATTR_TDLS_INITIATOR: flag attribute indicating the current end is
* the TDLS link initiator.
diff --git a/net/wireless/core.c b/net/wireless/core.c
index a4d2792..9d33df6 100644
--- a/net/wireless/core.c
+++ b/net/wireless/core.c
@@ -850,8 +850,10 @@ void __cfg80211_leave(struct cfg80211_registered_device *rdev,
break;
case NL80211_IFTYPE_P2P_CLIENT:
case NL80211_IFTYPE_STATION:
- if (rdev->sched_scan_req && dev == rdev->sched_scan_req->dev)
+ if (rdev->sched_scan_req && dev == rdev->sched_scan_req->dev) {
+ flush_work(&rdev->sched_scan_req->sched_scan_stop_wk);
__cfg80211_stop_sched_scan(rdev, false);
+ }
#ifdef CONFIG_CFG80211_WEXT
kfree(wdev->wext.ie);
@@ -991,6 +993,7 @@ static int cfg80211_netdev_notifier_call(struct notifier_block *nb,
if (WARN_ON(rdev->sched_scan_req &&
rdev->sched_scan_req->dev == wdev->netdev)) {
+ flush_work(&rdev->sched_scan_req->sched_scan_stop_wk);
__cfg80211_stop_sched_scan(rdev, false);
}
diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index df447c0..87a4b71 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -5681,6 +5681,22 @@ static int nl80211_trigger_scan(struct sk_buff *skb, struct genl_info *info)
return err;
}
+static void nl80211_sched_scan_stop_wk(struct work_struct *work)
+{
+ struct cfg80211_sched_scan_request *req;
+ struct cfg80211_registered_device *rdev;
+
+ req = container_of(work, struct cfg80211_sched_scan_request,
+ sched_scan_stop_wk);
+
+ rdev = wiphy_to_rdev(req->wiphy);
+
+ if (rtnl_trylock()) {
+ __cfg80211_stop_sched_scan(rdev, false);
+ rtnl_unlock();
+ }
+}
+
static int nl80211_start_sched_scan(struct sk_buff *skb,
struct genl_info *info)
{
@@ -5955,6 +5971,13 @@ static int nl80211_start_sched_scan(struct sk_buff *skb,
err = rdev_sched_scan_start(rdev, dev, request);
if (!err) {
+ if (info->attrs[NL80211_ATTR_SOCKET_OWNER]) {
+ INIT_WORK(&request->sched_scan_stop_wk,
+ nl80211_sched_scan_stop_wk);
+
+ request->owner_nlportid = info->snd_portid;
+ }
+
rdev->sched_scan_req = request;
nl80211_send_sched_scan(rdev, dev,
NL80211_CMD_START_SCHED_SCAN);
@@ -12127,6 +12150,12 @@ static int nl80211_netlink_notify(struct notifier_block * nb,
list_for_each_entry_rcu(rdev, &cfg80211_rdev_list, list) {
bool schedule_destroy_work = false;
+ bool schedule_scan_stop = false;
+ struct cfg80211_sched_scan_request *req = rdev->sched_scan_req;
+
+ if (req && req->owner_nlportid == notify->portid &&
+ notify->portid)
+ schedule_scan_stop = true;
list_for_each_entry_rcu(wdev, &rdev->wdev_list, list) {
cfg80211_mlme_unregister_socket(wdev, notify->portid);
@@ -12157,6 +12186,12 @@ static int nl80211_netlink_notify(struct notifier_block * nb,
spin_unlock(&rdev->destroy_list_lock);
schedule_work(&rdev->destroy_work);
}
+ } else if (schedule_scan_stop) {
+ req->owner_nlportid = 0;
+
+ if (rdev->ops->sched_scan_stop &&
+ rdev->wiphy.flags & WIPHY_FLAG_SUPPORTS_SCHED_SCAN)
+ schedule_work(&req->sched_scan_stop_wk);
}
}
--
1.8.3.1