This is a note to let you know that I've just added the patch titled
wifi: mt76: do not run mt76_unregister_device() on unregistered hw
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
wifi-mt76-do-not-run-mt76_unregister_device-on-unreg.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a6063f01bf941004005b90d18a5a7d07907fd727
Author: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Date: Thu Feb 23 00:10:25 2023 +0100
wifi: mt76: do not run mt76_unregister_device() on unregistered hw
[ Upstream commit 41130c32f3a18fcc930316da17f3a5f3bc326aa1 ]
Trying to probe a mt7921e pci card without firmware results in a
successful probe where ieee80211_register_hw hasn't been called. When
removing the driver, ieee802111_unregister_hw is called unconditionally
leading to a kernel NULL pointer dereference.
Fix the issue running mt76_unregister_device routine just for registered
hw.
Link: https://bugs.debian.org/1029116
Link: https://bugs.kali.org/view.php?id=8140
Reported-by: Stuart Hayhurst <stuart.a.hayhurst@xxxxxxxxx>
Fixes: 1c71e03afe4b ("mt76: mt7921: move mt7921_init_hw in a dedicated work")
Tested-by: Helmut Grohne <helmut@xxxxxxxxxxxx>
Signed-off-by: Lorenzo Bianconi <lorenzo@xxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx>
Link: https://lore.kernel.org/r/be3457d82f4e44bb71a22b2b5db27b644a37b1e1.1677107277.git.lorenzo@xxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/wireless/mediatek/mt76/mac80211.c b/drivers/net/wireless/mediatek/mt76/mac80211.c
index fc608b369b3cc..d75e999a80e1f 100644
--- a/drivers/net/wireless/mediatek/mt76/mac80211.c
+++ b/drivers/net/wireless/mediatek/mt76/mac80211.c
@@ -526,6 +526,7 @@ int mt76_register_phy(struct mt76_phy *phy, bool vht,
if (ret)
return ret;
+ set_bit(MT76_STATE_REGISTERED, &phy->state);
phy->dev->phys[phy->band_idx] = phy;
return 0;
@@ -536,6 +537,9 @@ void mt76_unregister_phy(struct mt76_phy *phy)
{
struct mt76_dev *dev = phy->dev;
+ if (!test_bit(MT76_STATE_REGISTERED, &phy->state))
+ return;
+
mt76_tx_status_check(dev, true);
ieee80211_unregister_hw(phy->hw);
dev->phys[phy->band_idx] = NULL;
@@ -663,6 +667,7 @@ int mt76_register_device(struct mt76_dev *dev, bool vht,
return ret;
WARN_ON(mt76_worker_setup(hw, &dev->tx_worker, NULL, "tx"));
+ set_bit(MT76_STATE_REGISTERED, &phy->state);
sched_set_fifo_low(dev->tx_worker.task);
return 0;
@@ -673,6 +678,9 @@ void mt76_unregister_device(struct mt76_dev *dev)
{
struct ieee80211_hw *hw = dev->hw;
+ if (!test_bit(MT76_STATE_REGISTERED, &dev->phy.state))
+ return;
+
if (IS_ENABLED(CONFIG_MT76_LEDS))
mt76_led_cleanup(dev);
mt76_tx_status_check(dev, true);
diff --git a/drivers/net/wireless/mediatek/mt76/mt76.h b/drivers/net/wireless/mediatek/mt76/mt76.h
index 32a77a0ae9da9..d8216243b0224 100644
--- a/drivers/net/wireless/mediatek/mt76/mt76.h
+++ b/drivers/net/wireless/mediatek/mt76/mt76.h
@@ -399,6 +399,7 @@ struct mt76_tx_cb {
enum {
MT76_STATE_INITIALIZED,
+ MT76_STATE_REGISTERED,
MT76_STATE_RUNNING,
MT76_STATE_MCU_RUNNING,
MT76_SCANNING,
