[android-common:android15-6.6 1/1] include/linux/fortify-string.h:70:29: warning: '__builtin_memcpy': specified size between 4294967272 and 4294967295 exceeds maximum object size 2147483647

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

tree:   https://android.googlesource.com/kernel/common android15-6.6
head:   33d0bb4218ed324364ecbbaef42f75f4479a2fc7
commit: 1359fd9eae29490c542e17c107cb41cfb8463138 [1/1] ARM: 9429/1: ioremap: Sync PGDs for VMALLOC shadow
config: arm-randconfig-r111-20250516 (https://download.01.org/0day-ci/archive/20250516/202505160507.TpdEr4cX-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 7.5.0
reproduce: (https://download.01.org/0day-ci/archive/20250516/202505160507.TpdEr4cX-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/202505160507.TpdEr4cX-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/string.h:294:0,
                    from include/linux/bitmap.h:11,
                    from include/linux/cpumask.h:12,
                    from include/linux/mm_types_task.h:14,
                    from include/linux/mm_types.h:5,
                    from include/linux/buildid.h:5,
                    from include/linux/module.h:14,
                    from arch/arm/mm/ioremap.c:24:
   In function 'memcpy_pgd.constprop',
       inlined from '__check_vmalloc_seq' at arch/arm/mm/ioremap.c:145:3:
>> include/linux/fortify-string.h:70:29: warning: '__builtin_memcpy': specified size between 4294967272 and 4294967295 exceeds maximum object size 2147483647 [-Wstringop-overflow=]
    #define __underlying_memcpy __builtin_memcpy
                                ^
   include/linux/fortify-string.h:662:2: note: in expansion of macro '__underlying_memcpy'
     __underlying_##op(p, q, __fortify_size);   \
     ^~~~~~~~~~~~~
   include/linux/fortify-string.h:707:26: note: in expansion of macro '__fortify_memcpy_chk'
    #define memcpy(p, q, s)  __fortify_memcpy_chk(p, q, s,   \
                             ^~~~~~~~~~~~~~~~~~~~
   arch/arm/mm/ioremap.c:135:2: note: in expansion of macro 'memcpy'
     memcpy(pgd_offset(mm, start), pgd_offset_k(start),
     ^~~~~~


vim +/__builtin_memcpy +70 include/linux/fortify-string.h

78a498c3a227f2 Alexander Potapenko 2022-10-24  59  
78a498c3a227f2 Alexander Potapenko 2022-10-24  60  #if defined(__SANITIZE_MEMORY__)
78a498c3a227f2 Alexander Potapenko 2022-10-24  61  /*
78a498c3a227f2 Alexander Potapenko 2022-10-24  62   * For KMSAN builds all memcpy/memset/memmove calls should be replaced by the
78a498c3a227f2 Alexander Potapenko 2022-10-24  63   * corresponding __msan_XXX functions.
78a498c3a227f2 Alexander Potapenko 2022-10-24  64   */
78a498c3a227f2 Alexander Potapenko 2022-10-24  65  #include <linux/kmsan_string.h>
78a498c3a227f2 Alexander Potapenko 2022-10-24  66  #define __underlying_memcpy	__msan_memcpy
78a498c3a227f2 Alexander Potapenko 2022-10-24  67  #define __underlying_memmove	__msan_memmove
78a498c3a227f2 Alexander Potapenko 2022-10-24  68  #define __underlying_memset	__msan_memset
78a498c3a227f2 Alexander Potapenko 2022-10-24  69  #else
a28a6e860c6cf2 Francis Laniel      2021-02-25 @70  #define __underlying_memcpy	__builtin_memcpy
a28a6e860c6cf2 Francis Laniel      2021-02-25  71  #define __underlying_memmove	__builtin_memmove
a28a6e860c6cf2 Francis Laniel      2021-02-25  72  #define __underlying_memset	__builtin_memset
78a498c3a227f2 Alexander Potapenko 2022-10-24  73  #endif
78a498c3a227f2 Alexander Potapenko 2022-10-24  74  

:::::: The code at line 70 was first introduced by commit
:::::: a28a6e860c6cf231cf3c5171c75c342adcd00406 string.h: move fortified functions definitions in a dedicated header.

:::::: TO: Francis Laniel <laniel_francis@privacyrequired.com>
:::::: CC: Linus Torvalds <torvalds@linux-foundation.org>

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests/wiki