From: Duoming Zhou duoming@zju.edu.cn
[ Upstream commit 6a0c054930d554ad8f8044ef1fc856d9da391c81 ]
There are sleep in atomic context bugs when dm_fsync_timer_callback is executing. The root cause is that the memory allocation functions with GFP_KERNEL or GFP_NOIO parameters are called in dm_fsync_timer_callback which is a timer handler. The call paths that could trigger bugs are shown below:
(interrupt context) dm_fsync_timer_callback write_nic_byte kzalloc(sizeof(data), GFP_KERNEL); //may sleep usb_control_msg kmalloc(.., GFP_NOIO); //may sleep write_nic_dword kzalloc(sizeof(data), GFP_KERNEL); //may sleep usb_control_msg kmalloc(.., GFP_NOIO); //may sleep
This patch uses delayed work to replace timer and moves the operations that may sleep into the delayed work in order to mitigate bugs.
Fixes: 8fc8598e61f6 ("Staging: Added Realtek rtl8192u driver to staging") Signed-off-by: Duoming Zhou duoming@zju.edu.cn Link: https://lore.kernel.org/r/20220710103002.63283-1-duoming@zju.edu.cn Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/staging/rtl8192u/r8192U.h | 2 +- drivers/staging/rtl8192u/r8192U_dm.c | 38 +++++++++++++--------------- drivers/staging/rtl8192u/r8192U_dm.h | 2 +- 3 files changed, 20 insertions(+), 22 deletions(-)
diff --git a/drivers/staging/rtl8192u/r8192U.h b/drivers/staging/rtl8192u/r8192U.h index 4013107cd93a..a23d6d41de9d 100644 --- a/drivers/staging/rtl8192u/r8192U.h +++ b/drivers/staging/rtl8192u/r8192U.h @@ -1013,7 +1013,7 @@ typedef struct r8192_priv { bool bis_any_nonbepkts; bool bcurrent_turbo_EDCA; bool bis_cur_rdlstate; - struct timer_list fsync_timer; + struct delayed_work fsync_work; bool bfsync_processing; /* 500ms Fsync timer is active or not */ u32 rate_record; u32 rateCountDiffRecord; diff --git a/drivers/staging/rtl8192u/r8192U_dm.c b/drivers/staging/rtl8192u/r8192U_dm.c index 725bf5ca9e34..0fcfcaa6500b 100644 --- a/drivers/staging/rtl8192u/r8192U_dm.c +++ b/drivers/staging/rtl8192u/r8192U_dm.c @@ -2578,19 +2578,20 @@ static void dm_init_fsync(struct net_device *dev) priv->ieee80211->fsync_seconddiff_ratethreshold = 200; priv->ieee80211->fsync_state = Default_Fsync; priv->framesyncMonitor = 1; /* current default 0xc38 monitor on */ - timer_setup(&priv->fsync_timer, dm_fsync_timer_callback, 0); + INIT_DELAYED_WORK(&priv->fsync_work, dm_fsync_work_callback); }
static void dm_deInit_fsync(struct net_device *dev) { struct r8192_priv *priv = ieee80211_priv(dev);
- del_timer_sync(&priv->fsync_timer); + cancel_delayed_work_sync(&priv->fsync_work); }
-void dm_fsync_timer_callback(struct timer_list *t) +void dm_fsync_work_callback(struct work_struct *work) { - struct r8192_priv *priv = from_timer(priv, t, fsync_timer); + struct r8192_priv *priv = + container_of(work, struct r8192_priv, fsync_work.work); struct net_device *dev = priv->ieee80211->dev; u32 rate_index, rate_count = 0, rate_count_diff = 0; bool bSwitchFromCountDiff = false; @@ -2657,17 +2658,16 @@ void dm_fsync_timer_callback(struct timer_list *t) } } if (bDoubleTimeInterval) { - if (timer_pending(&priv->fsync_timer)) - del_timer_sync(&priv->fsync_timer); - priv->fsync_timer.expires = jiffies + - msecs_to_jiffies(priv->ieee80211->fsync_time_interval*priv->ieee80211->fsync_multiple_timeinterval); - add_timer(&priv->fsync_timer); + cancel_delayed_work_sync(&priv->fsync_work); + schedule_delayed_work(&priv->fsync_work, + msecs_to_jiffies(priv + ->ieee80211->fsync_time_interval * + priv->ieee80211->fsync_multiple_timeinterval)); } else { - if (timer_pending(&priv->fsync_timer)) - del_timer_sync(&priv->fsync_timer); - priv->fsync_timer.expires = jiffies + - msecs_to_jiffies(priv->ieee80211->fsync_time_interval); - add_timer(&priv->fsync_timer); + cancel_delayed_work_sync(&priv->fsync_work); + schedule_delayed_work(&priv->fsync_work, + msecs_to_jiffies(priv + ->ieee80211->fsync_time_interval)); } } else { /* Let Register return to default value; */ @@ -2695,7 +2695,7 @@ static void dm_EndSWFsync(struct net_device *dev) struct r8192_priv *priv = ieee80211_priv(dev);
RT_TRACE(COMP_HALDM, "%s\n", __func__); - del_timer_sync(&(priv->fsync_timer)); + cancel_delayed_work_sync(&priv->fsync_work);
/* Let Register return to default value; */ if (priv->bswitch_fsync) { @@ -2736,11 +2736,9 @@ static void dm_StartSWFsync(struct net_device *dev) if (priv->ieee80211->fsync_rate_bitmap & rateBitmap) priv->rate_record += priv->stats.received_rate_histogram[1][rateIndex]; } - if (timer_pending(&priv->fsync_timer)) - del_timer_sync(&priv->fsync_timer); - priv->fsync_timer.expires = jiffies + - msecs_to_jiffies(priv->ieee80211->fsync_time_interval); - add_timer(&priv->fsync_timer); + cancel_delayed_work_sync(&priv->fsync_work); + schedule_delayed_work(&priv->fsync_work, + msecs_to_jiffies(priv->ieee80211->fsync_time_interval));
write_nic_dword(dev, rOFDM0_RxDetector2, 0x465c12cd); } diff --git a/drivers/staging/rtl8192u/r8192U_dm.h b/drivers/staging/rtl8192u/r8192U_dm.h index 0b2a1c688597..2159018b4e38 100644 --- a/drivers/staging/rtl8192u/r8192U_dm.h +++ b/drivers/staging/rtl8192u/r8192U_dm.h @@ -166,7 +166,7 @@ void dm_force_tx_fw_info(struct net_device *dev, void dm_init_edca_turbo(struct net_device *dev); void dm_rf_operation_test_callback(unsigned long data); void dm_rf_pathcheck_workitemcallback(struct work_struct *work); -void dm_fsync_timer_callback(struct timer_list *t); +void dm_fsync_work_callback(struct work_struct *work); void dm_cck_txpower_adjust(struct net_device *dev, bool binch14); void dm_shadow_init(struct net_device *dev); void dm_initialize_txpower_tracking(struct net_device *dev);