ARM: EXYNOS: Fix dereference of ERR_PTR returned by of_genpd_get_from_provider

commit 0b7dc0ff95237a53287e52f1aab7408ebf1c4085 upstream.

ERR_PTR was dereferenced during sub domain parsing, if parent domain
could not be obtained (because of invalid phandle or deferred
registration of parent domain).

The Exynos power domain code checked whether
of_genpd_get_from_provider() returned NULL and in that case it skipped
that power domain node. However this function returns ERR_PTR or valid
pointer, not NULL.

Fixes: 0f7807518fe1 ("ARM: EXYNOS: add support for sub-power domains")
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Kukjin Kim <kgene@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/arch/arm/mach-exynos/pm_domains.c b/arch/arm/mach-exynos/pm_domains.c
index 37266a8264372a9d8ab898aec6389476f707869f..1f02bcb350e59fae3f72c6a4d7e18ffa8037a468 100644 (file)
--- a/arch/arm/mach-exynos/pm_domains.c
+++ b/arch/arm/mach-exynos/pm_domains.c
@@ -169,7 +169,7 @@ no_clk:
                args.np = np;
                args.args_count = 0;
                child_domain = of_genpd_get_from_provider(&args);
-               if (!child_domain)
+               if (IS_ERR(child_domain))
                        continue;
 
                if (of_parse_phandle_with_args(np, "power-domains",
@@ -177,7 +177,7 @@ no_clk:
                        continue;
 
                parent_domain = of_genpd_get_from_provider(&args);
-               if (!parent_domain)
+               if (IS_ERR(parent_domain))
                        continue;
 
                if (pm_genpd_add_subdomain(parent_domain, child_domain))