7fc1e449d069dbc8159b8d0fcf572aa827e6678e
[openwrt/openwrt.git] / package / kernel / mac80211 / patches / 861-brcmfmac-workaround-bug-with-some-inconsistent-BSSes.patch
1 From: =?UTF-8?q?Rafa=C5=82=20Mi=C5=82ecki?= <zajec5@gmail.com>
2 Date: Thu, 9 Jul 2015 00:07:59 +0200
3 Subject: [PATCH] brcmfmac: workaround bug with some inconsistent BSSes state
4 MIME-Version: 1.0
5 Content-Type: text/plain; charset=UTF-8
6 Content-Transfer-Encoding: 8bit
7
8 Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
9 ---
10
11 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
12 +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
13 @@ -655,9 +655,37 @@ static struct wireless_dev *brcmf_cfg802
14 enum nl80211_iftype type,
15 struct vif_params *params)
16 {
17 + struct net_device *dev;
18 struct wireless_dev *wdev;
19 int err;
20
21 + /*
22 + * There is a bug with in-firmware BSS management. When adding virtual
23 + * interface brcmfmac first tells firmware to create new BSS and then
24 + * it creates new struct net_device.
25 + *
26 + * If creating/registering netdev(ice) fails, BSS remains in some bugged
27 + * state. It conflicts with existing BSSes by overtaking their auth
28 + * requests.
29 + *
30 + * It results in one BSS (addresss X) sending beacons and another BSS
31 + * (address Y) replying to authentication requests. This makes interface
32 + * unusable as AP.
33 + *
34 + * To workaround this bug we may try to guess if register_netdev(ice)
35 + * will fail. The most obvious case is using interface name that already
36 + * exists. This is actually quite likely with brcmfmac & some user space
37 + * scripts as brcmfmac doesn't allow deleting virtual interfaces.
38 + * So this bug can be triggered even by something trivial like:
39 + * iw dev wlan0 delete
40 + * iw phy phy0 interface add wlan0 type __ap
41 + */
42 + dev = dev_get_by_name(&init_net, name);
43 + if (dev) {
44 + dev_put(dev);
45 + return ERR_PTR(-ENFILE);
46 + }
47 +
48 brcmf_dbg(TRACE, "enter: %s type %d\n", name, type);
49 err = brcmf_vif_add_validate(wiphy_to_cfg(wiphy), type);
50 if (err) {