[PATCH] irqchip/stm32: fix init error handling

Dan Carpenter
2018-08-08T12:03:19Z

If there are any errors in stm32_exti_host_init() then it leads to a
NULL dereference in the callers. The function should clean up after
itself.

Fixes: f9fc1745501e ("irqchip/stm32: Add host and driver data structures")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>

diff --git a/drivers/irqchip/irq-stm32-exti.c b/drivers/irqchip/irq-stm32-exti.c
index 3df527fcf4e1..0a2088e12d96 100644
--- a/drivers/irqchip/irq-stm32-exti.c
+++ b/drivers/irqchip/irq-stm32-exti.c
@@ -603,17 +603,24 @@ stm32_exti_host_data *stm32_exti_host_init(const struct stm32_exti_drv_data *dd,
sizeof(struct stm32_exti_chip_data),
GFP_KERNEL);
if (!host_data->chips_data)
- return NULL;
+ goto free_host_data;

host_data->base = of_iomap(node, 0);
if (!host_data->base) {
pr_err("%pOF: Unable to map registers\n", node);
- return NULL;
+ goto free_chips_data;
}

stm32_host_data = host_data;

return host_data;
+
+free_chips_data:
+ kfree(host_data->chips_data);
+free_host_data:
+ kfree(host_data);
+
+ return NULL;
}

static struct
@@ -665,10 +672,8 @@ static int __init stm32_exti_init(const struct stm32_exti_drv_data *drv_data,
struct irq_domain *domain;

host_data = stm32_exti_host_init(drv_data, node);
- if (!host_data) {
- ret = -ENOMEM;
- goto out_free_mem;
- }
+ if (!host_data)
+ return -ENOMEM;

domain = irq_domain_add_linear(node, drv_data->bank_nr * IRQS_PER_BANK,
&irq_exti_domain_ops, NULL);
@@ -725,7 +730,6 @@ static int __init stm32_exti_init(const struct stm32_exti_drv_data *drv_data,
irq_domain_remove(domain);
out_unmap:
iounmap(host_data->base);
-out_free_mem:
kfree(host_data->chips_data);
kfree(host_data);
return ret;
@@ -752,10 +756,8 @@ __init stm32_exti_hierarchy_init(const struct stm32_exti_drv_data *drv_data,
}

host_data = stm32_exti_host_init(drv_data, node);
- if (!host_data) {
- ret = -ENOMEM;
- goto out_free_mem;
- }
+ if (!host_data)
+ return -ENOMEM;

for (i = 0; i < drv_data->bank_nr; i++)
stm32_exti_chip_init(host_data, i, node);
@@ -777,7 +779,6 @@ __init stm32_exti_hierarchy_init(const struct stm32_exti_drv_data *drv_data,

out_unmap:
iounmap(host_data->base);
-out_free_mem:
kfree(host_data->chips_data);
kfree(host_data);
return ret;