The error checking for of_count_phandle_with_args() does not handle negative error codes correctly. The problem is that "index" is a u32 so in the condition "if (index >= num_domains)" negative error codes stored in "num_domains" are type promoted to very high positive values and "index" is always going to be valid. Test for negative error codes first and then test if "index" is valid. Fixes: 3ccf3f0cd197 ("PM / Domains: Enable genpd_dev_pm_attach_by_id|name() for single PM domain") Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> --- drivers/pmdomain/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/pmdomain/core.c b/drivers/pmdomain/core.c index cd4429653093..ff5c7f2b69ce 100644 --- a/drivers/pmdomain/core.c +++ b/drivers/pmdomain/core.c @@ -3176,7 +3176,7 @@ struct device *genpd_dev_pm_attach_by_id(struct device *dev, /* Verify that the index is within a valid range. */ num_domains = of_count_phandle_with_args(dev->of_node, "power-domains", "#power-domain-cells"); - if (index >= num_domains) + if (num_domains < 0 || index >= num_domains) return NULL; /* Allocate and register device on the genpd bus. */ -- 2.47.2