[PATCH v4 5/7] gpio: gpiolib: Add a check to validate GPIO hwirq

[Lad Prabhakar]

Add a check to validate GPIO hwirq is always within the range of hwirq_max
set in the GPIO irq domain.

Signed-off-by: Lad Prabhakar <prabhakar.mahadev-lad.rj@xxxxxxxxxxxxxx>
---
 drivers/gpio/gpiolib.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 65e344a23c6a..c1de7bb54c13 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1028,6 +1028,7 @@ static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
 	 * it is necessary to keep this around.
 	 */
 	if (is_fwnode_irqchip(gc->irq.fwnode)) {
+		struct irq_domain *domain = gc->irq.domain;
 		int i;
 		int ret;
 
@@ -1061,6 +1062,11 @@ static void gpiochip_set_hierarchical_irqchip(struct gpio_chip *gc,
 					 i, ret);
 				continue;
 			}
+			if (WARN(hwirq >= domain->hwirq_max,
+				 "error: hwirq 0x%x is too large for %s\n",
+				 (int)hwirq, domain->name))
+				continue;
+
 			fwspec.fwnode = gc->irq.fwnode;
 			/* This is the hwirq for the GPIO line side of things */
 			fwspec.param[0] = hwirq;
@@ -1436,6 +1442,9 @@ static int gpiochip_to_irq(struct gpio_chip *gc, unsigned int offset)
 		ret = gc->irq.child_offset_to_irq(gc, offset, &hwirq);
 		if (ret)
 			return ret;
+		if (WARN(hwirq >= domain->hwirq_max,
+			 "error: hwirq 0x%x is too large for %s\n", (int)hwirq, domain->name))
+			return -EINVAL;
 		spec.fwnode = domain->fwnode;
 		spec.param_count = 2;
 		spec.param[0] = hwirq;
-- 
2.25.1