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

Another issue found by KASAN. The bit finding is buried inside the
dp_for_each_set_bit() macro (that passes on to for_each_set_bit() that
calls the bit stuff. These bit functions want an unsigned long pointer
as input and just dumbly casting leads to out-of-bounds accesses.
This fixes that.
Signed-off-by: Carsten Haitzler <carsten.haitzler@arm.com>
Reviewed-by: Steven Price <steven.price@arm.com>
Reviewed-by: James Qian Wang <james.qian.wang@arm.com>
Signed-off-by: Liviu Dudau <liviu.dudau@arm.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210204131102.68658-1-carsten.haitzler@foss.arm.com

drivers/gpu/drm/arm/display/include/malidp_utils.h

@@ -13,9 +13,6 @@
 #define has_bit(nr, mask)	(BIT(nr) & (mask))
 #define has_bits(bits, mask)	(((bits) & (mask)) == (bits))
 
-#define dp_for_each_set_bit(bit, mask) \
-	for_each_set_bit((bit), ((unsigned long *)&(mask)), sizeof(mask) * 8)
-
 #define dp_wait_cond(__cond, __tries, __min_range, __max_range)	\
 ({							\
 	int num_tries = __tries;			\

drivers/gpu/drm/arm/display/komeda/komeda_pipeline.c

@@ -46,8 +46,9 @@ void komeda_pipeline_destroy(struct komeda_dev *mdev,
 {
 	struct komeda_component *c;
 	int i;
+	unsigned long avail_comps = pipe->avail_comps;
 
-	dp_for_each_set_bit(i, pipe->avail_comps) {
+	for_each_set_bit(i, &avail_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, i);
 		komeda_component_destroy(mdev, c);
 	}
@@ -247,6 +248,7 @@ static void komeda_pipeline_dump(struct komeda_pipeline *pipe)
 {
 	struct komeda_component *c;
 	int id;
+	unsigned long avail_comps = pipe->avail_comps;
 
 	DRM_INFO("Pipeline-%d: n_layers: %d, n_scalers: %d, output: %s.\n",
 		 pipe->id, pipe->n_layers, pipe->n_scalers,
@@ -258,7 +260,7 @@ static void komeda_pipeline_dump(struct komeda_pipeline *pipe)
 		 pipe->of_output_links[1] ?
 		 pipe->of_output_links[1]->full_name : "none");
 
-	dp_for_each_set_bit(id, pipe->avail_comps) {
+	for_each_set_bit(id, &avail_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 
 		komeda_component_dump(c);
@@ -270,8 +272,9 @@ static void komeda_component_verify_inputs(struct komeda_component *c)
 	struct komeda_pipeline *pipe = c->pipeline;
 	struct komeda_component *input;
 	int id;
+	unsigned long supported_inputs = c->supported_inputs;
 
-	dp_for_each_set_bit(id, c->supported_inputs) {
+	for_each_set_bit(id, &supported_inputs, 32) {
 		input = komeda_pipeline_get_component(pipe, id);
 		if (!input) {
 			c->supported_inputs &= ~(BIT(id));
@@ -302,8 +305,9 @@ static void komeda_pipeline_assemble(struct komeda_pipeline *pipe)
 	struct komeda_component *c;
 	struct komeda_layer *layer;
 	int i, id;
+	unsigned long avail_comps = pipe->avail_comps;
 
-	dp_for_each_set_bit(id, pipe->avail_comps) {
+	for_each_set_bit(id, &avail_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 		komeda_component_verify_inputs(c);
 	}
@@ -355,13 +359,15 @@ void komeda_pipeline_dump_register(struct komeda_pipeline *pipe,
 {
 	struct komeda_component *c;
 	u32 id;
+	unsigned long avail_comps;
 
 	seq_printf(sf, "\n======== Pipeline-%d ==========\n", pipe->id);
 
 	if (pipe->funcs && pipe->funcs->dump_register)
 		pipe->funcs->dump_register(pipe, sf);
 
-	dp_for_each_set_bit(id, pipe->avail_comps) {
+	avail_comps = pipe->avail_comps;
+	for_each_set_bit(id, &avail_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 
 		seq_printf(sf, "\n------%s------\n", c->name);

drivers/gpu/drm/arm/display/komeda/komeda_pipeline_state.c

@@ -1231,14 +1231,15 @@ komeda_pipeline_unbound_components(struct komeda_pipeline *pipe,
 	struct komeda_pipeline_state *old = priv_to_pipe_st(pipe->obj.state);
 	struct komeda_component_state *c_st;
 	struct komeda_component *c;
-	u32 disabling_comps, id;
+	u32 id;
+	unsigned long disabling_comps;
 
 	WARN_ON(!old);
 
 	disabling_comps = (~new->active_comps) & old->active_comps;
 
 	/* unbound all disabling component */
-	dp_for_each_set_bit(id, disabling_comps) {
+	for_each_set_bit(id, &disabling_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 		c_st = komeda_component_get_state_and_set_user(c,
 				drm_st, NULL, new->crtc);
@@ -1286,7 +1287,8 @@ bool komeda_pipeline_disable(struct komeda_pipeline *pipe,
 	struct komeda_pipeline_state *old;
 	struct komeda_component *c;
 	struct komeda_component_state *c_st;
-	u32 id, disabling_comps = 0;
+	u32 id;
+	unsigned long disabling_comps;
 
 	old = komeda_pipeline_get_old_state(pipe, old_state);
 
@@ -1296,10 +1298,10 @@ bool komeda_pipeline_disable(struct komeda_pipeline *pipe,
 		disabling_comps = old->active_comps &
 				  pipe->standalone_disabled_comps;
 
-	DRM_DEBUG_ATOMIC("PIPE%d: active_comps: 0x%x, disabling_comps: 0x%x.\n",
+	DRM_DEBUG_ATOMIC("PIPE%d: active_comps: 0x%x, disabling_comps: 0x%lx.\n",
 			 pipe->id, old->active_comps, disabling_comps);
 
-	dp_for_each_set_bit(id, disabling_comps) {
+	for_each_set_bit(id, &disabling_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 		c_st = priv_to_comp_st(c->obj.state);
 
@@ -1330,16 +1332,17 @@ void komeda_pipeline_update(struct komeda_pipeline *pipe,
 	struct komeda_pipeline_state *new = priv_to_pipe_st(pipe->obj.state);
 	struct komeda_pipeline_state *old;
 	struct komeda_component *c;
-	u32 id, changed_comps = 0;
+	u32 id;
+	unsigned long changed_comps;
 
 	old = komeda_pipeline_get_old_state(pipe, old_state);
 
 	changed_comps = new->active_comps | old->active_comps;
 
-	DRM_DEBUG_ATOMIC("PIPE%d: active_comps: 0x%x, changed: 0x%x.\n",
+	DRM_DEBUG_ATOMIC("PIPE%d: active_comps: 0x%x, changed: 0x%lx.\n",
 			 pipe->id, new->active_comps, changed_comps);
 
-	dp_for_each_set_bit(id, changed_comps) {
+	for_each_set_bit(id, &changed_comps, 32) {
 		c = komeda_pipeline_get_component(pipe, id);
 
 		if (new->active_comps & BIT(c->id))