From 3318dc299b072a0511d6dfd8367f3304fb6d9827 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Tue, 22 Apr 2025 17:16:16 +0100 Subject: [PATCH] irqchip/gic-v2m: Prevent use after free of gicv2m_get_fwnode() With ACPI in place, gicv2m_get_fwnode() is registered with the pci subsystem as pci_msi_get_fwnode_cb(), which may get invoked at runtime during a PCI host bridge probe. But, the call back is wrongly marked as __init, causing it to be freed, while being registered with the PCI subsystem and could trigger: Unable to handle kernel paging request at virtual address ffff8000816c0400 gicv2m_get_fwnode+0x0/0x58 (P) pci_set_bus_msi_domain+0x74/0x88 pci_register_host_bridge+0x194/0x548 This is easily reproducible on a Juno board with ACPI boot. Retain the function for later use. Fixes: 0644b3daca28 ("irqchip/gic-v2m: acpi: Introducing GICv2m ACPI support") Signed-off-by: Suzuki K Poulose Signed-off-by: Thomas Gleixner Signed-off-by: Ingo Molnar Reviewed-by: Marc Zyngier Cc: stable@vger.kernel.org --- drivers/irqchip/irq-gic-v2m.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c index c69894861866..dc98c39d2b20 100644 --- a/drivers/irqchip/irq-gic-v2m.c +++ b/drivers/irqchip/irq-gic-v2m.c @@ -421,7 +421,7 @@ static int __init gicv2m_of_init(struct fwnode_handle *parent_handle, #ifdef CONFIG_ACPI static int acpi_num_msi; -static __init struct fwnode_handle *gicv2m_get_fwnode(struct device *dev) +static struct fwnode_handle *gicv2m_get_fwnode(struct device *dev) { struct v2m_data *data; -- 2.50.1