Hello,
My static analysis tool reports two possible ABBA deadlocks in the
mwifiex driver in Linux 5.10:
# DEADLOCK 1:
mwifiex_dequeue_tx_packet()
spin_lock_bh(&priv->wmm.ra_list_spinlock); --> Line 1432 (Lock A)
mwifiex_send_addba()
spin_lock_bh(&priv->sta_list_spinlock); --> Line 608 (Lock B)
mwifiex_process_sta_tx_pause()
spin_lock_bh(&priv->sta_list_spinlock); --> Line 398 (Lock B)
mwifiex_update_ralist_tx_pause()
spin_lock_bh(&priv->wmm.ra_list_spinlock); --> Line 941 (Lock A)
When mwifiex_dequeue_tx_packet() and mwifiex_process_sta_tx_pause() are
concurrently executed, the deadlock can occur.
# DEADLOCK 2:
mwifiex_dequeue_tx_packet()
spin_lock_bh(&priv->wmm.ra_list_spinlock); --> Line 1432 (Lock A)
mwifiex_send_addba()
spin_lock_bh(&priv->sta_list_spinlock); --> Line 608 (Lock B)
mwifiex_process_uap_tx_pause()
spin_lock_bh(&priv->sta_list_spinlock); --> Line 363 (Lock B)
mwifiex_update_ralist_tx_pause()
spin_lock_bh(&priv->wmm.ra_list_spinlock); --> Line 941 (Lock A)
When mwifiex_dequeue_tx_packet() and mwifiex_process_uap_tx_pause() are
concurrently executed, the deadlock can occur.
I am not quite sure whether these possible deadlocks are real and how to
fix them if they are real.
Any feedback would be appreciated, thanks :)
Reported-by: TOTE Robot <oslab@xxxxxxxxxxxxxxx>
Best wishes,
Jia-Ju Bai
