From c16ae609214e835692c33b1a090b5a15bf1b9e7e Mon Sep 17 00:00:00 2001 From: Antonio Borneo Date: Mon, 6 Jun 2022 18:27:54 +0200 Subject: irqchip/stm32-exti: Prevent illegal read due to unbounded DT value The value hwirq is received from DT. If it exceeds the maximum valid value it causes the code to address unexisting irq chips reading outside the array boundary. Check the value of hwirq before using it. Signed-off-by: Antonio Borneo Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20220606162757.415354-4-antonio.borneo@foss.st.com --- drivers/irqchip/irq-stm32-exti.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/irqchip') 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]; -- cgit v1.2.3-70-g09d2