From: Janusz Dziedzic <janusz.dziedzic@gmail.com> stable inclusion from stable-5.10.77 commit 04121b10cdf0361c0fac761a9264659935878693 bugzilla: 185677 https://gitee.com/openeuler/kernel/issues/I4IAP7 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=... -------------------------------- commit 689a0a9f505f7bffdefe6f17fddb41c8ab6344f6 upstream. Without the patch we fail: $ sudo brctl addbr br0 $ sudo brctl addif br0 wlp1s0 $ sudo iw wlp1s0 set 4addr on command failed: Device or resource busy (-16) Last command failed but iface was already in 4addr mode. Fixes: ad4bb6f8883a ("cfg80211: disallow bridging managed/adhoc interfaces") Signed-off-by: Janusz Dziedzic <janusz.dziedzic@gmail.com> Link: https://lore.kernel.org/r/20211024201546.614379-1-janusz.dziedzic@gmail.com [add fixes tag, fix indentation, edit commit log] Signed-off-by: Johannes Berg <johannes.berg@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Chen Jun <chenjun102@huawei.com> Acked-by: Weilong Chen <chenweilong@huawei.com> Signed-off-by: Chen Jun <chenjun102@huawei.com> --- net/wireless/util.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) diff --git a/net/wireless/util.c b/net/wireless/util.c index 4fb8d1b14e76..3f8c46bb6d9a 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1028,14 +1028,14 @@ int cfg80211_change_iface(struct cfg80211_registered_device *rdev, !(rdev->wiphy.interface_modes & (1 << ntype))) return -EOPNOTSUPP; - /* if it's part of a bridge, reject changing type to station/ibss */ - if (netif_is_bridge_port(dev) && - (ntype == NL80211_IFTYPE_ADHOC || - ntype == NL80211_IFTYPE_STATION || - ntype == NL80211_IFTYPE_P2P_CLIENT)) - return -EBUSY; - if (ntype != otype) { + /* if it's part of a bridge, reject changing type to station/ibss */ + if (netif_is_bridge_port(dev) && + (ntype == NL80211_IFTYPE_ADHOC || + ntype == NL80211_IFTYPE_STATION || + ntype == NL80211_IFTYPE_P2P_CLIENT)) + return -EBUSY; + dev->ieee80211_ptr->use_4addr = false; dev->ieee80211_ptr->mesh_id_up_len = 0; wdev_lock(dev->ieee80211_ptr); -- 2.20.1