(ITS#6744) memory leak when chasing referrals

[arthur@arthurdejong.org]

Full_Name: Arthur de Jong
Version: 2.4.23
OS: Debian
URL: 
Submission from: (NULL) (2001:888:1613:0:218:8bff:fe55:2c9f)


There seems to be a memory leak in the LDAP client library when casing
referrals. When the code below is run through valgrind it reports:

==30395== 4,184 (80 direct, 4,104 indirect) bytes in 1 blocks are definitely
lost in loss record 3 of 3
==30395==    at 0x402328F: calloc (vg_replace_malloc.c:467)
==30395==    by 0x41D2CDF: ber_memcalloc_x (in /usr/lib/liblber-2.4.so.2.5.6)
==30395==    by 0x40650A0: ldap_send_server_request (in
/usr/lib/libldap_r-2.4.so.2.5.6)
==30395==    by 0x4065EB1: ldap_chase_v3referrals (in
/usr/lib/libldap_r-2.4.so.2.5.6)
==30395==    by 0x40510A3: ldap_result (in /usr/lib/libldap_r-2.4.so.2.5.6)
==30395==    by 0x8048871: main (test.c:28)

The code below is not very pretty (does not include error handling) but should
free all returned buffers. I can also reproduce the above leak with the
ldapsearch command-line tool.

Some background:
  http://www.openldap.org/lists/openldap-technical/201012/msg00031.html
  http://lists.arthurdejong.org/nss-pam-ldapd-users/2010/msg00166.html

-----8<-- test.c --8<-----

#include <stdio.h>
#include <errno.h>

#define LDAP_DEPRECATED 1
#include <ldap.h>

int main(int argc,char *argv[])
{
  char *base="dc=test,dc=tld";
  char *filter="(objectClass=posixAccount)";
  char *attrs[] = { "uid", NULL };
  int i;
  LDAP *ld;
  LDAPMessage *msg=NULL;
  int msgid;
  char **values;
  /* set up connection */
  ldap_initialize(&ld,"ldap://localhost";;);
  i=3;
  ldap_set_option(ld,LDAP_OPT_PROTOCOL_VERSION,&i);
  ldap_simple_bind_s(ld,NULL,NULL);
  /* start search and handle results */
  ldap_search_ext(ld,base,LDAP_SCOPE_SUB,filter,attrs,
                  0,NULL,NULL,NULL,LDAP_NO_LIMIT,&msgid);
  while (1)
  {
    switch (ldap_result(ld,msgid,LDAP_MSG_ONE,NULL,&msg))
    {
      case LDAP_RES_SEARCH_ENTRY:
        /* we have a normal search entry, print some attribute values */
        values=ldap_get_values(ld,msg,attrs[0]);
        for (i=0;values[i]!=NULL;i++)
          fprintf(stderr,"%s=%s\n",attrs[0],values[i]);
        ldap_value_free(values);
        break;
      case LDAP_RES_SEARCH_RESULT:
        /* end of results */
        ldap_msgfree(msg);
        ldap_unbind(ld);
        return 0;
      case LDAP_RES_SEARCH_REFERENCE:
        break; /* just ignore search references */
      default:
        /* we have some error condition, bail out */
        return -1;
    }
    ldap_msgfree(msg);
  }
}

-----8<-- test.c --8<-----