From c957280ef6ab6bdf559a91ae693a6b34310697e3 Mon Sep 17 00:00:00 2001 From: Deren Wu Date: Sat, 13 Jan 2024 17:00:22 +0800 Subject: wifi: mt76: mt7921e: fix use-after-free in free_irq() From commit a304e1b82808 ("[PATCH] Debug shared irqs"), there is a test to make sure the shared irq handler should be able to handle the unexpected event after deregistration. For this case, let's apply MT76_REMOVED flag to indicate the device was removed and do not run into the resource access anymore. BUG: KASAN: use-after-free in mt7921_irq_handler+0xd8/0x100 [mt7921e] Read of size 8 at addr ffff88824a7d3b78 by task rmmod/11115 CPU: 28 PID: 11115 Comm: rmmod Tainted: G W L 5.17.0 #10 Hardware name: Micro-Star International Co., Ltd. MS-7D73/MPG B650I EDGE WIFI (MS-7D73), BIOS 1.81 01/05/2024 Call Trace: dump_stack_lvl+0x6f/0xa0 print_address_description.constprop.0+0x1f/0x190 ? mt7921_irq_handler+0xd8/0x100 [mt7921e] ? mt7921_irq_handler+0xd8/0x100 [mt7921e] kasan_report.cold+0x7f/0x11b ? mt7921_irq_handler+0xd8/0x100 [mt7921e] mt7921_irq_handler+0xd8/0x100 [mt7921e] free_irq+0x627/0xaa0 devm_free_irq+0x94/0xd0 ? devm_request_any_context_irq+0x160/0x160 ? kobject_put+0x18d/0x4a0 mt7921_pci_remove+0x153/0x190 [mt7921e] pci_device_remove+0xa2/0x1d0 __device_release_driver+0x346/0x6e0 driver_detach+0x1ef/0x2c0 bus_remove_driver+0xe7/0x2d0 ? __check_object_size+0x57/0x310 pci_unregister_driver+0x26/0x250 __do_sys_delete_module+0x307/0x510 ? free_module+0x6a0/0x6a0 ? fpregs_assert_state_consistent+0x4b/0xb0 ? rcu_read_lock_sched_held+0x10/0x70 ? syscall_enter_from_user_mode+0x20/0x70 ? trace_hardirqs_on+0x1c/0x130 do_syscall_64+0x5c/0x80 ? trace_hardirqs_on_prepare+0x72/0x160 ? do_syscall_64+0x68/0x80 ? trace_hardirqs_on_prepare+0x72/0x160 entry_SYSCALL_64_after_hwframe+0x44/0xae Reported-by: Mikhail Gavrilov Closes: https://lore.kernel.org/linux-wireless/CABXGCsOdvVwdLmSsC8TZ1jF0UOg_F_W3wqLECWX620PUkvNk=A@mail.gmail.com/ Fixes: 9270270d6219 ("wifi: mt76: mt7921: fix PCI DMA hang after reboot") Tested-by: Mikhail Gavrilov Signed-off-by: Deren Wu Signed-off-by: Felix Fietkau --- drivers/net/wireless/mediatek/mt76/mt7921/pci.c | 1 + drivers/net/wireless/mediatek/mt76/mt792x_dma.c | 2 ++ 2 files changed, 3 insertions(+) (limited to 'drivers/net/wireless/mediatek/mt76') diff --git a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c index dde26f327478..82cf3ce90b52 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7921/pci.c +++ b/drivers/net/wireless/mediatek/mt76/mt7921/pci.c @@ -387,6 +387,7 @@ static void mt7921_pci_remove(struct pci_dev *pdev) struct mt792x_dev *dev = container_of(mdev, struct mt792x_dev, mt76); mt7921e_unregister_device(dev); + set_bit(MT76_REMOVED, &mdev->phy.state); devm_free_irq(&pdev->dev, pdev->irq, dev); mt76_free_device(&dev->mt76); pci_free_irq_vectors(pdev); diff --git a/drivers/net/wireless/mediatek/mt76/mt792x_dma.c b/drivers/net/wireless/mediatek/mt76/mt792x_dma.c index 8fa36b59e738..5cc2d59b774a 100644 --- a/drivers/net/wireless/mediatek/mt76/mt792x_dma.c +++ b/drivers/net/wireless/mediatek/mt76/mt792x_dma.c @@ -12,6 +12,8 @@ irqreturn_t mt792x_irq_handler(int irq, void *dev_instance) { struct mt792x_dev *dev = dev_instance; + if (test_bit(MT76_REMOVED, &dev->mt76.phy.state)) + return IRQ_NONE; mt76_wr(dev, dev->irq_map->host_irq_enable, 0); if (!test_bit(MT76_STATE_INITIALIZED, &dev->mphy.state)) -- cgit v1.2.3