genl: reject invalid group names in genl_family_add_grp()

The compiler warns about string truncation:

  In function ‘genl_family_add_grp’,
      inlined from ‘family_clone’ at lib/genl/family.c:81:9,
      inlined from ‘family_clone’ at lib/genl/family.c:66:12:
  lib/genl/family.c:376:2: error: ‘strncpy’ output may be truncated copying 15 bytes from a string of length 15 [-Werror=stringop-truncation]
    376 |  strncpy(grp->name, name, GENL_NAMSIZ - 1);
        |  ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Obvioulsy, it's a bug to use an invalid group name. But better
handle it by checking for a suitable string length.

Also use _nl_strncpy() which asserts that no truncation occurs.

0 files changed, 0 insertions, 0 deletions