wifi: cfg80211: clear link ID from bitmap during link delete after clean up

Vulnerability Description

In the Linux kernel, the following vulnerability has been resolved: wifi: cfg80211: clear link ID from bitmap during link delete after clean up Currently, during link deletion, the link ID is first removed from the valid_links bitmap before performing any clean-up operations. However, some functions require the link ID to remain in the valid_links bitmap. One such example is cfg80211_cac_event(). The flow is - nl80211_remove_link() cfg80211_remove_link() ieee80211_del_intf_link() ieee80211_vif_set_links() ieee80211_vif_update_links() ieee80211_link_stop() cfg80211_cac_event() cfg80211_cac_event() requires link ID to be present but it is cleared already in cfg80211_remove_link(). Ultimately, WARN_ON() is hit. Therefore, clear the link ID from the bitmap only after completing the link clean-up.

References

• https://git.kernel.org/stable/c/ae07daf440d3220d0986e676317a5da66e4f9dfd
• https://git.kernel.org/stable/c/b5c32ff6a3a38c74facdd1fe34c0d709a55527fd