1  /* Check for descriptor leak in if_nametoindex with a long interface name.
       2     Copyright (C) 2018-2023 Free Software Foundation, Inc.
       3     This file is part of the GNU C Library.
       4  
       5     The GNU C Library is free software; you can redistribute it and/or
       6     modify it under the terms of the GNU Lesser General Public
       7     License as published by the Free Software Foundation; either
       8     version 2.1 of the License, or (at your option) any later version.
       9  
      10     The GNU C Library is distributed in the hope that it will be useful,
      11     but WITHOUT ANY WARRANTY; without even the implied warranty of
      12     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
      13     Lesser General Public License for more details.
      14  
      15     You should have received a copy of the GNU Lesser General Public
      16     License along with the GNU C Library; if not, see
      17     <https://www.gnu.org/licenses/>.  */
      18  
      19  /* This test checks for a descriptor leak in case of a long interface
      20     name (CVE-2018-19591, bug 23927).  */
      21  
      22  #include <errno.h>
      23  #include <net/if.h>
      24  #include <netdb.h>
      25  #include <string.h>
      26  #include <support/check.h>
      27  #include <support/descriptors.h>
      28  #include <support/support.h>
      29  
      30  static int
      31  do_test (void)
      32  {
      33    struct support_descriptors *descrs = support_descriptors_list ();
      34  
      35    /* Prepare a name which is just as long as required for trigging the
      36       bug.  */
      37    char name[IFNAMSIZ + 1];
      38    memset (name, 'A', IFNAMSIZ);
      39    name[IFNAMSIZ] = '\0';
      40    TEST_COMPARE (strlen (name), IFNAMSIZ);
      41    struct ifreq ifr;
      42    TEST_COMPARE (strlen (name), sizeof (ifr.ifr_name));
      43  
      44    /* Test directly via if_nametoindex.  */
      45    TEST_COMPARE (if_nametoindex (name), 0);
      46    TEST_COMPARE (errno, ENODEV);
      47    support_descriptors_check (descrs);
      48  
      49    /* Same test via getaddrinfo.  */
      50    char *host = xasprintf ("fea0::%%%s", name);
      51    struct addrinfo hints = { .ai_flags = AI_NUMERICHOST, };
      52    struct addrinfo *ai;
      53    TEST_COMPARE (getaddrinfo (host, NULL, &hints, &ai), EAI_NONAME);
      54    support_descriptors_check (descrs);
      55  
      56    support_descriptors_free (descrs);
      57  
      58    return 0;
      59  }
      60  
      61  #include <support/test-driver.c>