CVE-2024-47713

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

wifi: mac80211: use two-phase skb reclamation in ieee80211_do_stop()

Since '__dev_queue_xmit()' should be called with interrupts enabled, the following backtrace:

ieee80211_do_stop() ... spin_lock_irqsave(&local->queue_stop_reason_lock, flags) ... ieee80211_free_txskb() ieee80211_report_used_skb() ieee80211_report_ack_skb() cfg80211_mgmt_tx_status_ext() nl80211_frame_tx_status() genlmsg_multicast_netns() genlmsg_multicast_netns_filtered() nlmsg_multicast_filtered() netlink_broadcast_filtered() do_one_broadcast() netlink_broadcast_deliver() __netlink_sendskb() netlink_deliver_tap() __netlink_deliver_tap_skb() dev_queue_xmit() __dev_queue_xmit() ; with IRQS disabled ... spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags)

issues the warning (as reported by syzbot reproducer):

WARNING: CPU: 2 PID: 5128 at kernel/softirq.c:362 __local_bh_enable_ip+0xc3/0x120

Fix this by implementing a two-phase skb reclamation in 'ieee80211_do_stop()', where actual work is performed outside of a section with interrupts disabled.