Input: ff-core - make use of __free() cleanup facility

Annotate allocated memory with __free(kfree) to simplify the code and
make sure memory is released appropriately.

Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Link: https://lore.kernel.org/r/20241107071538.195340-3-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>

Author: dtor

drivers/input/ff-core.c

@@ -290,8 +290,6 @@ EXPORT_SYMBOL_GPL(input_ff_event);
  */
 int input_ff_create(struct input_dev *dev, unsigned int max_effects)
 {
-	struct ff_device *ff;
-	size_t ff_dev_size;
 	int i;
 
 	if (!max_effects) {
@@ -304,25 +302,19 @@ int input_ff_create(struct input_dev *dev, unsigned int max_effects)
 		return -EINVAL;
 	}
 
-	ff_dev_size = struct_size(ff, effect_owners, max_effects);
-	if (ff_dev_size == SIZE_MAX) /* overflow */
-		return -EINVAL;
-
-	ff = kzalloc(ff_dev_size, GFP_KERNEL);
+	struct ff_device *ff __free(kfree) =
+		kzalloc(struct_size(ff, effect_owners, max_effects),
+			GFP_KERNEL);
 	if (!ff)
 		return -ENOMEM;
 
-	ff->effects = kcalloc(max_effects, sizeof(struct ff_effect),
-			      GFP_KERNEL);
-	if (!ff->effects) {
-		kfree(ff);
+	ff->effects = kcalloc(max_effects, sizeof(*ff->effects), GFP_KERNEL);
+	if (!ff->effects)
 		return -ENOMEM;
-	}
 
 	ff->max_effects = max_effects;
 	mutex_init(&ff->mutex);
 
-	dev->ff = ff;
 	dev->flush = input_ff_flush;
 	dev->event = input_ff_event;
 	__set_bit(EV_FF, dev->evbit);
@@ -335,6 +327,8 @@ int input_ff_create(struct input_dev *dev, unsigned int max_effects)
 	if (test_bit(FF_PERIODIC, ff->ffbit))
 		__set_bit(FF_RUMBLE, dev->ffbit);
 
+	dev->ff = no_free_ptr(ff);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(input_ff_create);