s4:dsdb/pydsdb.c - clean up memory handling

- Remove memory contexts when not really useful (if only one allocation)
- Try to find out OOM conditions and return correct error codes
- Move the parameter parsing always to the beginning (to prevent
  unneeded allocations in case of errors)

diff --git a/source4/dsdb/pydsdb.c b/source4/dsdb/pydsdb.c
index f5832d1d3972ad0cc164338b13b583736c59f903..bdac7902aa9a391c283f1a65d98db00bc9721935 100644 (file)
--- a/source4/dsdb/pydsdb.c
+++ b/source4/dsdb/pydsdb.c
@@ -17,11 +17,9 @@
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
-#include <Python.h>
+#include "lib/ldb/pyldb.h"
 #include "includes.h"
-#include "libcli/util/pyerrors.h"
 #include "dsdb/samdb/samdb.h"
-#include "lib/ldb/pyldb.h"
 #include "libcli/security/security.h"
 #include "librpc/ndr/libndr.h"
 #include "system/kerberos.h"
@@ -81,6 +79,10 @@ static PyObject *py_samdb_server_site_name(PyObject *self, PyObject *args)
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
        mem_ctx = talloc_new(NULL);
+       if (mem_ctx == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
 
        site = samdb_server_site_name(ldb, mem_ctx);
        if (site == NULL) {
@@ -133,6 +135,10 @@ static PyObject *py_samdb_set_domain_sid(PyLdbObject *self, PyObject *args)
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
        sid = dom_sid_parse_talloc(NULL, PyString_AsString(py_sid));
+       if (sid == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
 
        ret = samdb_set_domain_sid(ldb, sid);
        talloc_free(sid);
@@ -153,7 +159,7 @@ static PyObject *py_samdb_set_ntds_settings_dn(PyLdbObject *self, PyObject *args
 
        if (!PyArg_ParseTuple(args, "OO", &py_ldb, &py_ntds_settings_dn))
                return NULL;
-       
+
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
        tmp_ctx = talloc_new(NULL);
@@ -163,6 +169,8 @@ static PyObject *py_samdb_set_ntds_settings_dn(PyLdbObject *self, PyObject *args
        }
 
        if (!PyObject_AsDn(tmp_ctx, py_ntds_settings_dn, ldb, &ntds_settings_dn)) {
+               PyErr_NoMemory();
+               talloc_free(tmp_ctx);
                return NULL;
        }
 
@@ -185,15 +193,20 @@ static PyObject *py_samdb_get_domain_sid(PyLdbObject *self, PyObject *args)
 
        if (!PyArg_ParseTuple(args, "O", &py_ldb))
                return NULL;
-       
+
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
        sid = samdb_domain_sid(ldb);
        if (!sid) {
                PyErr_SetString(PyExc_RuntimeError, "samdb_domain_sid failed");
                return NULL;
-       } 
+       }
+
        retstr = dom_sid_string(NULL, sid);
+       if (retstr == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
        ret = PyString_FromString(retstr);
        talloc_free(retstr);
        return ret;
@@ -203,17 +216,10 @@ static PyObject *py_samdb_ntds_invocation_id(PyObject *self, PyObject *args)
 {
        PyObject *py_ldb, *result;
        struct ldb_context *ldb;
-       TALLOC_CTX *mem_ctx;
        const struct GUID *guid;
-
-       mem_ctx = talloc_new(NULL);
-       if (mem_ctx == NULL) {
-               PyErr_NoMemory();
-               return NULL;
-       }
+       char *retstr;
 
        if (!PyArg_ParseTuple(args, "O", &py_ldb)) {
-               talloc_free(mem_ctx);
                return NULL;
        }
 
@@ -223,12 +229,16 @@ static PyObject *py_samdb_ntds_invocation_id(PyObject *self, PyObject *args)
        if (guid == NULL) {
                PyErr_SetString(PyExc_RuntimeError,
                                                "Failed to find NTDS invocation ID");
-               talloc_free(mem_ctx);
                return NULL;
        }
 
-       result = PyString_FromString(GUID_string(mem_ctx, guid));
-       talloc_free(mem_ctx);
+       retstr = GUID_string(NULL, guid);
+       if (retstr == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
+       result = PyString_FromString(retstr);
+       talloc_free(retstr);
        return result;
 }
 
@@ -240,7 +250,6 @@ static PyObject *py_dsdb_get_oid_from_attid(PyObject *self, PyObject *args)
        struct dsdb_schema *schema;
        const char *oid;
        PyObject *ret;
-       TALLOC_CTX *mem_ctx;
        WERROR status;
 
        if (!PyArg_ParseTuple(args, "Oi", &py_ldb, &attid))
@@ -248,27 +257,19 @@ static PyObject *py_dsdb_get_oid_from_attid(PyObject *self, PyObject *args)
 
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
-       mem_ctx = talloc_new(NULL);
-       if (mem_ctx == NULL) {
-          PyErr_NoMemory();
-          return NULL;
-       }
-
        schema = dsdb_get_schema(ldb, NULL);
 
        if (!schema) {
                PyErr_SetString(PyExc_RuntimeError, "Failed to find a schema from ldb \n");
-               talloc_free(mem_ctx);
                return NULL;
        }
        
        status = dsdb_schema_pfm_oid_from_attid(schema->prefixmap, attid,
-                                               mem_ctx, &oid);
+                                               NULL, &oid);
        PyErr_WERROR_IS_ERR_RAISE(status);
 
        ret = PyString_FromString(oid);
-
-       talloc_free(mem_ctx);
+       talloc_free(discard_const_p(char, oid));
 
        return ret;
 }
@@ -361,11 +362,28 @@ static PyObject *py_dsdb_DsReplicaAttribute(PyObject *self, PyObject *args)
        syntax_ctx.is_schema_nc = false;
 
        tmp_ctx = talloc_new(ldb);
+       if (tmp_ctx == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
 
        el = talloc_zero(tmp_ctx, struct ldb_message_element);
+       if (el == NULL) {
+               PyErr_NoMemory();
+               talloc_free(tmp_ctx);
+               return NULL;
+       }
+
        el->name = ldap_display_name;
        el->num_values = PyList_Size(el_list);
+
        el->values = talloc_array(el, struct ldb_val, el->num_values);
+       if (el->values == NULL) {
+               PyErr_NoMemory();
+               talloc_free(tmp_ctx);
+               return NULL;
+       }
+
        for (i = 0; i < el->num_values; i++) {
                PyObject *item = PyList_GetItem(el_list, i);
                if (!PyString_Check(item)) {
@@ -377,13 +395,18 @@ static PyObject *py_dsdb_DsReplicaAttribute(PyObject *self, PyObject *args)
        }
 
        attr = talloc_zero(tmp_ctx, struct drsuapi_DsReplicaAttribute);
+       if (attr == NULL) {
+               PyErr_NoMemory();
+               talloc_free(tmp_ctx);
+               return NULL;
+       }
 
        werr = a->syntax->ldb_to_drsuapi(&syntax_ctx, a, el, attr, attr);
        PyErr_WERROR_IS_ERR_RAISE(werr);
 
        ret = py_return_ndr_struct("samba.dcerpc.drsuapi", "DsReplicaAttribute", attr, attr);
 
-       talloc_unlink(ldb, tmp_ctx);
+       talloc_free(tmp_ctx);
 
        return ret;
 }
@@ -412,8 +435,8 @@ static PyObject *py_samdb_ntds_objectGUID(PyObject *self, PyObject *args)
 {
        PyObject *py_ldb, *result;
        struct ldb_context *ldb;
-       TALLOC_CTX *mem_ctx;
        const struct GUID *guid;
+       char *retstr;
 
        if (!PyArg_ParseTuple(args, "O", &py_ldb)) {
                return NULL;
@@ -421,21 +444,19 @@ static PyObject *py_samdb_ntds_objectGUID(PyObject *self, PyObject *args)
 
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
-       mem_ctx = talloc_new(NULL);
-       if (mem_ctx == NULL) {
-               PyErr_NoMemory();
-               return NULL;
-       }
-
        guid = samdb_ntds_objectGUID(ldb);
        if (guid == NULL) {
                PyErr_SetString(PyExc_RuntimeError, "Failed to find NTDS GUID");
-               talloc_free(mem_ctx);
                return NULL;
        }
 
-       result = PyString_FromString(GUID_string(mem_ctx, guid));
-       talloc_free(mem_ctx);
+       retstr = GUID_string(NULL, guid);
+       if (retstr == NULL) {
+               PyErr_NoMemory();
+               return NULL;
+       }
+       result = PyString_FromString(retstr);
+       talloc_free(retstr);
        return result;
 }
 
@@ -464,19 +485,18 @@ static PyObject *py_dsdb_load_partition_usn(PyObject *self, PyObject *args)
        TALLOC_CTX *mem_ctx;
        int ret;
 
+       if (!PyArg_ParseTuple(args, "OO", &py_ldb, &py_dn)) {
+               return NULL;
+       }
+
+       PyErr_LDB_OR_RAISE(py_ldb, ldb);
+
        mem_ctx = talloc_new(NULL);
        if (mem_ctx == NULL) {
           PyErr_NoMemory();
           return NULL;
        }
 
-       if (!PyArg_ParseTuple(args, "OO", &py_ldb, &py_dn)) {
-          talloc_free(mem_ctx);
-          return NULL;
-       }
-
-       PyErr_LDB_OR_RAISE(py_ldb, ldb);
-
        if (!PyObject_AsDn(mem_ctx, py_dn, ldb, &dn)) {
           talloc_free(mem_ctx);
           return NULL;
@@ -597,7 +617,6 @@ static PyObject *py_dsdb_get_partitions_dn(PyObject *self, PyObject *args)
        struct ldb_context *ldb;
        struct ldb_dn *dn;
        PyObject *py_ldb, *ret;
-       TALLOC_CTX *tmp_ctx;
        PyObject *mod;
 
        mod = PyImport_ImportModule("ldb");
@@ -607,16 +626,13 @@ static PyObject *py_dsdb_get_partitions_dn(PyObject *self, PyObject *args)
 
        PyErr_LDB_OR_RAISE(py_ldb, ldb);
 
-       tmp_ctx = talloc_new(NULL);
-
-       dn = samdb_partitions_dn(ldb, tmp_ctx);
-
+       dn = samdb_partitions_dn(ldb, NULL);
        if (dn == NULL) {
-               talloc_free(tmp_ctx);
-               Py_RETURN_NONE;
+               PyErr_NoMemory();
+               return NULL;
        }
        ret = PyLdbDn_FromDn(dn);
-       talloc_free(tmp_ctx);
+       talloc_free(dn);
        return ret;
 }