[PATCH] pdb_ldap: Don't use autofree if "mods" still changes

[Volker Lendecke]

Hi!

Review appreciated!

Thanks, Volker

-- 
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From 7cc7b3e575381e1ff83660332cc4f3ef0d2bcd1e Mon Sep 17 00:00:00 2001
From: Volker Lendecke <vl at samba.org>
Date: Fri, 4 Mar 2016 10:51:33 +0100
Subject: [PATCH] pdb_ldap: Don't use autofree if "mods" still changes

This will prevent some use-after-free's, potentially it might for example fix
bugzilla 11851. Not directly related, but it's a crash related to ldap-backed
user creation.

Signed-off-by: Volker Lendecke <vl at samba.org>
---
 source3/passdb/pdb_ldap.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/source3/passdb/pdb_ldap.c b/source3/passdb/pdb_ldap.c
index 50ab3a7..4383785 100644
--- a/source3/passdb/pdb_ldap.c
+++ b/source3/passdb/pdb_ldap.c
@@ -5291,10 +5291,10 @@ static NTSTATUS ldapsam_create_user(struct pdb_methods *my_methods,
 	}
 
 	init_okay = init_ldap_from_sam(ldap_state, entry, &mods, user, pdb_element_is_set_or_changed);
-	smbldap_talloc_autofree_ldapmod(tmp_ctx, mods);
 
 	if (!init_okay) {
 		DEBUG(1,("ldapsam_create_user: Unable to fill user structs\n"));
+		ldap_mods_free(mods, true);
 		return NT_STATUS_UNSUCCESSFUL;
 	}
 
@@ -5312,12 +5312,14 @@ static NTSTATUS ldapsam_create_user(struct pdb_methods *my_methods,
 		if (!sid_compose(&group_sid, get_global_sam_sid(), DOMAIN_RID_USERS) ||
 		    !sid_to_gid(&group_sid, &gid)) {
 			DEBUG (0, ("ldapsam_create_user: Unable to get the Domain Users gid: bailing out!\n"));
+			ldap_mods_free(mods, true);
 			return NT_STATUS_INVALID_PRIMARY_GROUP;
 		}
 
 		/* lets allocate a new userid for this user */
 		if (!winbind_allocate_uid(&uid)) {
 			DEBUG (0, ("ldapsam_create_user: Unable to allocate a new user id: bailing out!\n"));
+			ldap_mods_free(mods, true);
 			return NT_STATUS_UNSUCCESSFUL;
 		}
 
@@ -5354,6 +5356,7 @@ static NTSTATUS ldapsam_create_user(struct pdb_methods *my_methods,
 		escape_name = escape_rdn_val_string_alloc(name);
 		if (!escape_name) {
 			DEBUG (0, ("ldapsam_create_user: Out of memory!\n"));
+			ldap_mods_free(mods, true);
 			return NT_STATUS_NO_MEMORY;
 		}
 
@@ -5367,6 +5370,7 @@ static NTSTATUS ldapsam_create_user(struct pdb_methods *my_methods,
 
 		if (!homedir || !shell || !uidstr || !gidstr || !dn) {
 			DEBUG (0, ("ldapsam_create_user: Out of memory!\n"));
+			ldap_mods_free(mods, true);
 			return NT_STATUS_NO_MEMORY;
 		}
 
@@ -5385,6 +5389,8 @@ static NTSTATUS ldapsam_create_user(struct pdb_methods *my_methods,
 		rc = smbldap_modify(ldap_state->smbldap_state, dn, mods);
 	}	
 
+	ldap_mods_free(mods, true);
+
 	if (rc != LDAP_SUCCESS) {
 		DEBUG(0,("ldapsam_create_user: failed to create a new user [%s] (dn = %s)\n", name ,dn));
 		return NT_STATUS_UNSUCCESSFUL;
-- 
2.1.4