Duoming Zhou ffc9cab724 drivers: staging: rtl8192u: Fix deadlock in ieee80211_beacons_stop() ... [ Upstream commit 806c7b5341 ] There is a deadlock in ieee80211_beacons_stop(), which is shown below: (Thread 1) | (Thread 2) | ieee80211_send_beacon() ieee80211_beacons_stop() | mod_timer() spin_lock_irqsave() //(1) | (wait a time) ... | ieee80211_send_beacon_cb() del_timer_sync() | spin_lock_irqsave() //(2) (wait timer to stop) | ... We hold ieee->beacon_lock in position (1) of thread 1 and use del_timer_sync() to wait timer to stop, but timer handler also need ieee->beacon_lock in position (2) of thread 2. As a result, ieee80211_beacons_stop() will block forever. This patch extracts del_timer_sync() from the protection of spin_lock_irqsave(), which could let timer handler to obtain the needed lock. Signed-off-by: Duoming Zhou <duoming@zju.edu.cn> Link: https://lore.kernel.org/r/20220417135407.109536-1-duoming@zju.edu.cn Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-06-14 18:41:34 +02:00
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dot11d.c	staging/rtl8192u/ieee80211: remove debugging line	2020-10-26 06:53:10 +01:00
dot11d.h
ieee80211.h	staging: rtl8192u: Avoid field-overflowing memcpy()	2021-08-10 12:09:35 +02:00
ieee80211_crypt.c
ieee80211_crypt.h
ieee80211_crypt_ccmp.c	staging: rtl8192u: Avoid field-overflowing memcpy()	2021-08-10 12:09:35 +02:00
ieee80211_crypt_tkip.c	mm: remove kzfree() compatibility definition	2020-10-25 11:39:02 -07:00
ieee80211_crypt_wep.c	mm: remove kzfree() compatibility definition	2020-10-25 11:39:02 -07:00
ieee80211_module.c
ieee80211_rx.c	staging: rtl8192u: Avoid field-overflowing memcpy()	2021-08-10 12:09:35 +02:00
ieee80211_softmac.c	drivers: staging: rtl8192u: Fix deadlock in ieee80211_beacons_stop()	2022-06-14 18:41:34 +02:00
ieee80211_softmac_wx.c	staging: rtl8192u: Switch from strlcpy to strscpy	2021-02-04 17:16:07 +01:00
ieee80211_tx.c	staging: rtl8192u: Fix shadowed variable name	2021-06-03 15:56:54 +02:00
ieee80211_wx.c	staging: rtl8192u: ieee80211: Remove braces for single line blocks	2021-03-12 17:31:28 +01:00
rtl819x_BA.h
rtl819x_BAProc.c	staging: rt8192u: change constants to be on right	2021-04-07 10:21:44 +02:00
rtl819x_HT.h
rtl819x_HTProc.c
rtl819x_Qos.h
rtl819x_TS.h
rtl819x_TSProc.c