mm: move debug checks from __vunmap to remove_vm_area

All these checks apply to the free_vm_area interface as well, so move them
to the common routine.

Link: https://lkml.kernel.org/r/20230121071051.1143058-9-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

mm/vmalloc.c

@@ -2573,11 +2573,20 @@ struct vm_struct *remove_vm_area(const void *addr)
 
 	might_sleep();
 
+	if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
+			addr))
+		return NULL;
+
 	va = find_unlink_vmap_area((unsigned long)addr);
 	if (!va || !va->vm)
 		return NULL;
 	vm = va->vm;
+
+	debug_check_no_locks_freed(vm->addr, get_vm_area_size(vm));
+	debug_check_no_obj_freed(vm->addr, get_vm_area_size(vm));
 	kasan_free_module_shadow(vm);
+	kasan_poison_vmalloc(vm->addr, get_vm_area_size(vm));
+
 	free_unmap_vmap_area(va);
 	return vm;
 }
@@ -2649,10 +2658,6 @@ static void __vunmap(const void *addr, int deallocate_pages)
 	if (!addr)
 		return;
 
-	if (WARN(!PAGE_ALIGNED(addr), "Trying to vfree() bad address (%p)\n",
-			addr))
-		return;
-
 	area = remove_vm_area(addr);
 	if (unlikely(!area)) {
 		WARN(1, KERN_ERR "Trying to vfree() nonexistent vm area (%p)\n",
@@ -2660,11 +2665,6 @@ static void __vunmap(const void *addr, int deallocate_pages)
 		return;
 	}
 
-	debug_check_no_locks_freed(area->addr, get_vm_area_size(area));
-	debug_check_no_obj_freed(area->addr, get_vm_area_size(area));
-
-	kasan_poison_vmalloc(area->addr, get_vm_area_size(area));
-
 	vm_remove_mappings(area, deallocate_pages);
 
 	if (deallocate_pages) {