[ Upstream commit 9d301de12da6e1bb069a9835c38359b8e8135121 ]
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.
Fixes: 5061b0c2b906 ("mac80211: cooperate more with network namespaces")
Reported-by: syzbot+1a3986bbd3169c307819@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=1a3986bbd3169c307819
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Link: https://patch.msgid.link/20240906123151.351647-1-dmantipov@yandex.ru
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
25eb51c765