Fix some null pointer dereferences in LDAP auth code

An LDAP URL without a host name such as "ldap://" or without a base DN
such as "ldap://localhost" would cause a crash when reading pg_hba.conf.

If no binddn is configured, an error message might end up trying to print a
null pointer, which could crash on some platforms.

Author: Thomas Munro <thomas.munro@enterprisedb.com>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>

diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 6030aa5e8748bda8f57da5ddb6e252a1c3a0826c..8fb518dbc24773d97c038164a0a3f5dd4c703d2a 100644 (file)
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -2018,7 +2018,8 @@ CheckLDAPAuth(Port *port)
                {
                        ereport(LOG,
                                        (errmsg("could not perform initial LDAP bind for ldapbinddn \"%s\" on server \"%s\": %s",
-                                                       port->hba->ldapbinddn, port->hba->ldapserver, ldap_err2string(r))));
+                                                       port->hba->ldapbinddn ? port->hba->ldapbinddn : "",
+                                                       port->hba->ldapserver, ldap_err2string(r))));
                        return STATUS_ERROR;
                }
 

diff --git a/src/backend/libpq/hba.c b/src/backend/libpq/hba.c
index b4b608c220bbb6c88d692caebe3d2920b905f29c..18b5a6b3b97b995b0d1bfb1a3d1adccff3b159c9 100644 (file)
--- a/src/backend/libpq/hba.c
+++ b/src/backend/libpq/hba.c
@@ -1464,9 +1464,11 @@ parse_hba_auth_opt(char *name, char *val, HbaLine *hbaline, int line_num)
                        return false;
                }
 
-               hbaline->ldapserver = pstrdup(urldata->lud_host);
+               if (urldata->lud_host)
+                       hbaline->ldapserver = pstrdup(urldata->lud_host);
                hbaline->ldapport = urldata->lud_port;
-               hbaline->ldapbasedn = pstrdup(urldata->lud_dn);
+               if (urldata->lud_dn)
+                       hbaline->ldapbasedn = pstrdup(urldata->lud_dn);
 
                if (urldata->lud_attrs)
                        hbaline->ldapsearchattribute = pstrdup(urldata->lud_attrs[0]);          /* only use first one */