wifi: mac80211: prevent AP VLAN tx from other interfaces

Overview

In the Linux kernel, the following vulnerability has been resolved:

wifi: mac80211: prevent AP VLAN tx from other interfaces

Since the station lookup was factored out of ieee80211_build_hdr(), ieee80211_lookup_ra_sta() uses sta_info_get_bss() for all AP and AP VLAN frames, not only for control port frames. A unicast frame sent on one interface thus matches a station of a different VLAN of the same BSS and is transmitted to it.

Only match stations of the interface the frame is sent on, except for control port frames, since those may be sent for VLAN stations directly on the BSS interface.

Affected

• Linux >= 97ffe75791b3e9c0797d5891070e41321c3beccb < fd875e24e8f2b202e3636b3ef8e6060874eca0e5
• Linux >= 97ffe75791b3e9c0797d5891070e41321c3beccb < 88e96d902efeefbffc34450969f40dc61a0c8a42
• Linux >= 97ffe75791b3e9c0797d5891070e41321c3beccb < ad61b9a5febb42e4b96df8d30ad76ddc36dda9d0
• Linux >= 97ffe75791b3e9c0797d5891070e41321c3beccb < 7f93ca31f7fd9b42e7d692f59514436d448ac908
• Linux 4.1

Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.