diff mbox series

[v2,3/6] irqchip/stm32-exti: Prevent illegal read due to unbounded DT value

Message ID 20220606162757.415354-4-antonio.borneo@foss.st.com (mailing list archive)
State New, archived
Headers show
Series None | expand

Commit Message

Antonio Borneo June 6, 2022, 4:27 p.m. UTC 
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 <antonio.borneo@foss.st.com>
---
 drivers/irqchip/irq-stm32-exti.c | 3 +++
 1 file changed, 3 insertions(+)
diff mbox series

Patch

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];