diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
index 1145f064faa8..e2722e499ae5 100644
--- a/drivers/irqchip/irq-stm32-exti.c
+++ b/drivers/irqchip/irq-stm32-exti.c
@@ -713,6 +713,9 @@ static int stm32_exti_h_domain_alloc(struct irq_domain *dm,
 	int bank;
 
 	hwirq = fwspec->param[0];
+	if (hwirq >= host_data->drv_data->bank_nr * IRQS_PER_BANK)
+		return -EINVAL;
+
 	bank  = hwirq / IRQS_PER_BANK;
 	chip_data = &host_data->chips_data[bank];