From: Leon Yen leon.yen@mediatek.com

stable inclusion from stable-v6.6.36 commit 85edd783f4539a994d66c4c014d5858f490b7a02 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IACR0E CVE: CVE-2024-40977

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

---------------------------

[ Upstream commit ecf0b2b8a37c8464186620bef37812a117ff6366 ]

During chip recovery (e.g. chip reset), there is a possible situation that kernel worker reset_work is holding the lock and waiting for kernel thread stat_worker to be parked, while stat_worker is waiting for the release of the same lock. It causes a deadlock resulting in the dumping of hung tasks messages and possible rebooting of the device.

This patch prevents the execution of stat_worker during the chip recovery.

Signed-off-by: Leon Yen leon.yen@mediatek.com Signed-off-by: Ming Yen Hsieh MingYen.Hsieh@mediatek.com Signed-off-by: Felix Fietkau nbd@nbd.name Signed-off-by: Sasha Levin sashal@kernel.org Signed-off-by: Zhengchao Shao shaozhengchao@huawei.com --- drivers/net/wireless/mediatek/mt76/mt7921/mac.c | 2 ++ drivers/net/wireless/mediatek/mt76/mt7921/pci_mac.c | 2 -- drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c | 2 -- drivers/net/wireless/mediatek/mt76/sdio.c | 3 ++- 4 files changed, 4 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c index 21f937454229..cd4eee374922 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/mac.c @@ -663,6 +663,7 @@ void mt7921_mac_reset_work(struct work_struct *work) int i, ret;

dev_dbg(dev->mt76.dev, "chip reset\n"); + set_bit(MT76_RESET, &dev->mphy.state); dev->hw_full_reset = true; ieee80211_stop_queues(hw);

@@ -691,6 +692,7 @@ void mt7921_mac_reset_work(struct work_struct *work) }

dev->hw_full_reset = false; + clear_bit(MT76_RESET, &dev->mphy.state); pm->suspended = false; ieee80211_wake_queues(hw); ieee80211_iterate_active_interfaces(hw, diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci_mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci_mac.c index c866144ff061..031ba9aaa4e2 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci_mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci_mac.c @@ -64,7 +64,6 @@ int mt7921e_mac_reset(struct mt792x_dev *dev) mt76_wr(dev, dev->irq_map->host_irq_enable, 0); mt76_wr(dev, MT_PCIE_MAC_INT_ENABLE, 0x0);

- set_bit(MT76_RESET, &dev->mphy.state); set_bit(MT76_MCU_RESET, &dev->mphy.state); wake_up(&dev->mt76.mcu.wait); skb_queue_purge(&dev->mt76.mcu.res_q); @@ -115,7 +114,6 @@ int mt7921e_mac_reset(struct mt792x_dev *dev)

err = __mt7921_start(&dev->phy); out: - clear_bit(MT76_RESET, &dev->mphy.state);

local_bh_disable(); napi_enable(&dev->mt76.tx_napi); diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c index 389eb0903807..1f77cf71ca70 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/sdio_mac.c @@ -98,7 +98,6 @@ int mt7921s_mac_reset(struct mt792x_dev *dev) mt76_connac_free_pending_tx_skbs(&dev->pm, NULL); mt76_txq_schedule_all(&dev->mphy); mt76_worker_disable(&dev->mt76.tx_worker); - set_bit(MT76_RESET, &dev->mphy.state); set_bit(MT76_MCU_RESET, &dev->mphy.state); wake_up(&dev->mt76.mcu.wait); skb_queue_purge(&dev->mt76.mcu.res_q); @@ -135,7 +134,6 @@ int mt7921s_mac_reset(struct mt792x_dev *dev)

err = __mt7921_start(&dev->phy); out: - clear_bit(MT76_RESET, &dev->mphy.state);

mt76_worker_enable(&dev->mt76.tx_worker);

diff --git a/drivers/net/wireless/mediatek/mt76/sdio.c b/drivers/net/wireless/mediatek/mt76/sdio.c index c52d550f0c32..2c761d469c06 100644 --- a/drivers/net/wireless/mediatek/mt76/sdio.c +++ b/drivers/net/wireless/mediatek/mt76/sdio.c @@ -499,7 +499,8 @@ static void mt76s_tx_status_data(struct mt76_worker *worker) dev = container_of(sdio, struct mt76_dev, sdio);

while (true) { - if (test_bit(MT76_REMOVED, &dev->phy.state)) + if (test_bit(MT76_RESET, &dev->phy.state) || + test_bit(MT76_REMOVED, &dev->phy.state)) break;

if (!dev->drv->tx_status_data(dev, &update))