Re: fortify: add KUnit tests for __counted_by and __counted_by_ptr

[kernel test robot <lkp@intel.com>]

Hi Bill,

kernel test robot noticed the following build warnings:



url:    https://github.com/intel-lab-lkp/linux/commits/Bill-Wendling/fortify-add-KUnit-tests-for-__counted_by-and-__counted_by_ptr/20260929-010031
base:   
patch link:    https://lore.kernel.org/r/202609301715.SnFPA5YE-lkp%40intel.com
config: x86_64-randconfig-2300-20260930 (https://download.01.org/0day-ci/archive/20260930/202609301715.SnFPA5YE-lkp@intel.com/config)
compiler: clang version 22.1.8 (https://github.com/llvm/llvm-project ca7933e47d3a3451d81e72ac174dcb5aa28b59d1)
sparse: v0.6.5-rc1
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260930/202609301715.SnFPA5YE-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202609301715.SnFPA5YE-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   lib/tests/fortify_kunit.c:1049:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1049:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
>> lib/tests/fortify_kunit.c:1049:9: sparse: sparse: incompatible types for operation (==):
   lib/tests/fortify_kunit.c:1049:9: sparse:    unsigned long const __left
   lib/tests/fortify_kunit.c:1049:9: sparse:    bad type const __right
   lib/tests/fortify_kunit.c:1051:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1051:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1051:9: sparse: sparse: incompatible types for operation (==):
   lib/tests/fortify_kunit.c:1051:9: sparse:    unsigned long const __left
   lib/tests/fortify_kunit.c:1051:9: sparse:    bad type const __right
   lib/tests/fortify_kunit.c:1106:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1106:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1106:9: sparse: sparse: incompatible types for operation (==):
   lib/tests/fortify_kunit.c:1106:9: sparse:    unsigned long const __left
   lib/tests/fortify_kunit.c:1106:9: sparse:    bad type const __right
   lib/tests/fortify_kunit.c:1107:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1107:9: sparse: sparse: undefined identifier '__builtin_dynamic_object_size'
   lib/tests/fortify_kunit.c:1107:9: sparse: sparse: incompatible types for operation (==):
   lib/tests/fortify_kunit.c:1107:9: sparse:    unsigned long const __left
   lib/tests/fortify_kunit.c:1107:9: sparse:    bad type const __right

vim +1049 lib/tests/fortify_kunit.c

  1036	
  1037	static void fortify_test_counted_by_flex(struct kunit *test)
  1038	{
  1039		size_t size = 128;
  1040		struct counted_by_flex_struct *s;
  1041		size_t elem_bytes = size * sizeof(s->array[0]);
  1042	
  1043		s = alloc_counted_by_flex_struct(test, size);
  1044	
  1045		OPTIMIZER_HIDE_VAR(s);
  1046		OPTIMIZER_HIDE_VAR(elem_bytes);
  1047	
  1048		/* __builtin_dynamic_object_size() should return the logical length. */
> 1049		KUNIT_EXPECT_EQ(test, elem_bytes,
  1050				__builtin_dynamic_object_size(s->array, 0));
  1051		KUNIT_EXPECT_EQ(test, elem_bytes,
  1052				__builtin_dynamic_object_size(s->array, 1));
  1053	
  1054		/* Within-bounds write and read succeed. */
  1055		memset(s->array, 0x42, elem_bytes);
  1056		KUNIT_EXPECT_EQ(test, fortify_write_overflows, 0);
  1057		KUNIT_EXPECT_NOT_NULL(test, memchr(s->array, 0x42, elem_bytes));
  1058		KUNIT_EXPECT_EQ(test, fortify_read_overflows, 0);
  1059	
  1060		/* Out-of-bounds write and read past logical size are caught. */
  1061		memset(s->array, 0x42, elem_bytes + 1);
  1062		KUNIT_EXPECT_EQ(test, fortify_write_overflows, 1);
  1063		KUNIT_EXPECT_NULL(test, memchr(s->array, 0x42, elem_bytes + 1));
  1064		KUNIT_EXPECT_EQ(test, fortify_read_overflows, 1);
  1065	
  1066		kfree(s);
  1067	}
  1068	

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