6.6-stable review patch. If anyone has any objections, please let me know. ------------------ From: Duoming Zhou [ Upstream commit c8f62f73bbced3a79894655bdb0b625462d956fc ] When the mt7996 pci chip is detaching, the mt7996_crash_data is released in mt7996_coredump_unregister(). However, the work item dump_work may still be running or pending, leading to UAF bugs when the already freed crash_data is dereferenced again in mt7996_mac_dump_work(). The race condition can occur as follows: CPU 0 (removal path) | CPU 1 (workqueue) mt7996_pci_remove() | mt7996_sys_recovery_set() mt7996_unregister_device() | mt7996_reset() mt7996_coredump_unregister() | queue_work() vfree(dev->coredump.crash_data) | mt7996_mac_dump_work() | crash_data-> // UAF Fix this by ensuring dump_work is properly canceled before the crash_data is deallocated. Add cancel_work_sync() in mt7996_unregister_device() to synchronize with any pending or executing dump work. Fixes: 878161d5d4a4 ("wifi: mt76: mt7996: enable coredump support") Signed-off-by: Duoming Zhou Link: https://patch.msgid.link/20260131024731.18741-1-duoming@zju.edu.cn Signed-off-by: Felix Fietkau Signed-off-by: Sasha Levin --- drivers/net/wireless/mediatek/mt76/mt7996/init.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/init.c b/drivers/net/wireless/mediatek/mt76/mt7996/init.c index fa81a1c30704b..ed066acfbfa92 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7996/init.c +++ b/drivers/net/wireless/mediatek/mt76/mt7996/init.c @@ -930,6 +930,7 @@ int mt7996_register_device(struct mt7996_dev *dev) void mt7996_unregister_device(struct mt7996_dev *dev) { + cancel_work_sync(&dev->dump_work); mt7996_unregister_phy(mt7996_phy3(dev), MT_BAND2); mt7996_unregister_phy(mt7996_phy2(dev), MT_BAND1); mt7996_coredump_unregister(dev); -- 2.53.0