drm/komeda: Fix bit check to import to value of proper type

KASAN found this problem. find_first_bit() expects to look at a
pointer pointing to a long, but we look at a u32 - this is going to be
an issue with endianness but, KSAN already flags this as out-of-bounds
stack reads. This fixes it by just importing inot a local long.

Signed-off-by: Carsten Haitzler <carsten.haitzler@arm.com>
Acked-by: Liviu Dudau <liviu.dudau@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20201218150812.68195-1-carsten.haitzler@foss.arm.com

diff --git a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.c b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.c
index 452e505..719a797 100644 (file)
--- a/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.c
+++ b/drivers/gpu/drm/arm/display/komeda/komeda_pipeline.c
@@ -137,9 +137,10 @@ komeda_pipeline_get_first_component(struct komeda_pipeline *pipe,
                                    u32 comp_mask)
 {
        struct komeda_component *c = NULL;
+       unsigned long comp_mask_local = (unsigned long)comp_mask;
        int id;
 
-       id = find_first_bit((unsigned long *)&comp_mask, 32);
+       id = find_first_bit(&comp_mask_local, 32);
        if (id < 32)
                c = komeda_pipeline_get_component(pipe, id);