2018-10-19 21:22:05

by Andrew Zaborowski

[permalink] [raw]
Subject: [PATCH v2] nl80211: Emit a SET_INTERFACE on iftype change

Let userspace learn about iftype changes by sending a notification
when handling the NL80211_CMD_SET_INTERFACE command. There seems
to be no other place where the iftype can change: nl80211_set_interface
is the only caller of cfg80211_change_iface which is the only caller of
ops->change_virtual_intf.

Signed-off-by: Andrew Zaborowski <[email protected]>
---
net/wireless/nl80211.c | 28 ++++++++++++++++------------
1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/net/wireless/nl80211.c b/net/wireless/nl80211.c
index ac08ba5f0a..de727a69c4 100644
--- a/net/wireless/nl80211.c
+++ b/net/wireless/nl80211.c
@@ -2788,14 +2788,15 @@ static int nl80211_send_chandef(struct sk_buff *msg,

static int nl80211_send_iface(struct sk_buff *msg, u32 portid, u32 seq, int flags,
struct cfg80211_registered_device *rdev,
- struct wireless_dev *wdev, bool removal)
+ struct wireless_dev *wdev,
+ enum nl80211_commands cmd)
{
struct net_device *dev = wdev->netdev;
- u8 cmd = NL80211_CMD_NEW_INTERFACE;
void *hdr;

- if (removal)
- cmd = NL80211_CMD_DEL_INTERFACE;
+ WARN_ON(cmd != NL80211_CMD_NEW_INTERFACE &&
+ cmd != NL80211_CMD_DEL_INTERFACE &&
+ cmd != NL80211_CMD_SET_INTERFACE);

hdr = nl80211hdr_put(msg, portid, seq, flags, cmd);
if (!hdr)
@@ -2943,7 +2944,8 @@ static int nl80211_dump_interface(struct sk_buff *skb, struct netlink_callback *
}
if (nl80211_send_iface(skb, NETLINK_CB(cb->skb).portid,
cb->nlh->nlmsg_seq, NLM_F_MULTI,
- rdev, wdev, false) < 0) {
+ rdev, wdev,
+ NL80211_CMD_NEW_INTERFACE) < 0) {
goto out;
}
if_idx++;
@@ -2973,7 +2975,7 @@ static int nl80211_get_interface(struct sk_buff *skb, struct genl_info *info)
return -ENOMEM;

if (nl80211_send_iface(msg, info->snd_portid, info->snd_seq, 0,
- rdev, wdev, false) < 0) {
+ rdev, wdev, NL80211_CMD_NEW_INTERFACE) < 0) {
nlmsg_free(msg);
return -ENOBUFS;
}
@@ -3165,6 +3167,12 @@ static int nl80211_set_interface(struct sk_buff *skb, struct genl_info *info)
if (!err && params.use_4addr != -1)
dev->ieee80211_ptr->use_4addr = params.use_4addr;

+ if (change && !err) {
+ struct wireless_dev *wdev = dev->ieee80211_ptr;
+
+ nl80211_notify_iface(rdev, wdev, NL80211_CMD_SET_INTERFACE);
+ }
+
return err;
}

@@ -3267,7 +3275,7 @@ static int nl80211_new_interface(struct sk_buff *skb, struct genl_info *info)
}

if (nl80211_send_iface(msg, info->snd_portid, info->snd_seq, 0,
- rdev, wdev, false) < 0) {
+ rdev, wdev, NL80211_CMD_NEW_INTERFACE) < 0) {
nlmsg_free(msg);
return -ENOBUFS;
}
@@ -13946,15 +13954,11 @@ void nl80211_notify_iface(struct cfg80211_registered_device *rdev,
{
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) {
+ if (nl80211_send_iface(msg, 0, 0, 0, rdev, wdev, cmd) < 0) {
nlmsg_free(msg);
return;
}
--
2.19.1