sql_cacher: Fix pkg memory leaks

(cherry picked from commit e72fc5f)

cachedb/cachedb.h

@@ -62,8 +62,8 @@ void cachedb_do_close(cachedb_con *con, void (*free_connection)(cachedb_pool_con
 typedef cachedb_con* (cachedb_init_f)(str *url);
 typedef void (cachedb_destroy_f)(cachedb_con *con);
 
-/* NOTE: "val->s" must be allocated in PKG memory,
- * and will be freed by the CacheDB layer! */
+/* NOTE: "val->s" shall be allocated in PKG memory,
+ * and MUST be freed by the calling layer! */
 typedef int (cachedb_get_f)(cachedb_con *con,str *attr,str *val);
 typedef int (cachedb_getcounter_f)(cachedb_con *con,str *attr,int *val);
 typedef int (cachedb_set_f)(cachedb_con *con,str *attr,str *val,int expires);

modules/sql_cacher/sql_cacher.c

@@ -612,6 +612,7 @@ static db_handlers_t *db_init_test_conn(cache_entry_t *c_entry)
 	db_res_t *sql_res;
 	str cachedb_res;
 	unsigned int i;
+	int rc;
 
 	new_db_hdls = pkg_malloc(sizeof(db_handlers_t));
 	if (!new_db_hdls) {
@@ -653,7 +654,9 @@ static db_handlers_t *db_init_test_conn(cache_entry_t *c_entry)
 		new_db_hdls->cdbcon = 0;
 		return NULL;
 	}
-	if (str_strcmp(&cachedb_res, &cdb_test_val) != 0) {
+	rc = str_strcmp(&cachedb_res, &cdb_test_val);
+	pkg_free(cachedb_res.s);
+	if (rc != 0) {
 		LM_ERR("Inconsistent test key for cachedb: %.*s\n",
 			c_entry->cachedb_url.len, c_entry->cachedb_url.s);
 		new_db_hdls->cdbf.destroy(new_db_hdls->cdbcon);
@@ -1206,7 +1209,7 @@ static int cdb_val_decode(pv_name_fix_t *pv_name, str *cdb_val, int reload_versi
 
 	if (pv_name->col_offset == -1) {
 		LM_WARN("Unknown column %.*s\n", pv_name->col.len, pv_name->col.s);
-		return -1;
+		return 2;
 	}
 
 	if (!pv_name->c_entry->on_demand) {
@@ -1217,7 +1220,7 @@ static int cdb_val_decode(pv_name_fix_t *pv_name, str *cdb_val, int reload_versi
 		memcpy(&int_val, int_buf, 4);
 
 		if (reload_version != int_val)
-			return -2;
+			return 3;
 	}
 
 	/* null integer value in db */
@@ -1263,7 +1266,7 @@ static int cdb_val_decode(pv_name_fix_t *pv_name, str *cdb_val, int reload_versi
 	return 0;
 error:
 	LM_ERR("Failed to decode value: %.*s from cachedb\n", cdb_val->len, cdb_val->s);
-	return -1;
+	return 2;
 }
 
 static void optimize_cdb_decode(pv_name_fix_t *pv_name)
@@ -1557,6 +1560,7 @@ int pv_parse_name(pv_spec_p sp, str *in)
 	return 0;
 }
 
+static str valbuff;
 int pv_get_sql_cached_value(struct sip_msg *msg,  pv_param_t *param, pv_value_t *res)
 {
 	pv_name_fix_t *pv_name;
@@ -1616,7 +1620,7 @@ int pv_get_sql_cached_value(struct sip_msg *msg,  pv_param_t *param, pv_value_t
 	}
 
 	if (!pv_name->c_entry->on_demand) {
-		if (rc == -2) {
+		if (rc <= -2) {
 			LM_DBG("key %.*s not found in SQL db\n", pv_name->key.len, pv_name->key.s);
 			lock_stop_read(pv_name->c_entry->ref_lock);
 			return pv_get_null(msg, param, res);
@@ -1628,28 +1632,30 @@ int pv_get_sql_cached_value(struct sip_msg *msg,  pv_param_t *param, pv_value_t
 
 			lock_stop_read(pv_name->c_entry->ref_lock);
 
-			if (rc2 == -1)
-				return pv_get_null(msg, param, res);
-			if (rc2 == -2) {
+			if (rc2 == 2)
+				goto out_free_null;
+			if (rc2 == 3) {
 				LM_DBG("key %.*s not found in SQL db\n", pv_name->key.len, pv_name->key.s);
-				return pv_get_null(msg, param, res);
+				goto out_free_null;
 			}
 			if (rc2 == 1) {
 				LM_DBG("NULL value in SQL db\n");
-				return pv_get_null(msg, param, res);
+				goto out_free_null;
 			}
 		}
 	} else {
-		if (rc == -2) {
+		if (rc <= -2) {
 			rc2 = on_demand_load(pv_name, &cdb_res, &str_res, &int_res);
 			if (rc2 == -1 || rc2 == -2)
 				return pv_get_null(msg, param, res);
+			if (rc2 == 2 || rc2 == 3)
+				goto out_free_null;
 			if (rc2 == 1) {
 				LM_DBG("NULL value in SQL db\n");
-				return pv_get_null(msg, param, res);
+				goto out_free_null;
 			}
 		} else {
-			if (!cdb_res.len || !cdb_res.s) {
+			if (cdb_res.len == 0 || !cdb_res.s) {
 				LM_DBG("key %.*s not found in SQL db\n", pv_name->key.len, pv_name->key.s);
 				return pv_get_null(msg, param, res);
 			}
@@ -1658,18 +1664,26 @@ int pv_get_sql_cached_value(struct sip_msg *msg,  pv_param_t *param, pv_value_t
 				optimize_cdb_decode(pv_name);
 
 			rc2 = cdb_val_decode(pv_name, &cdb_res, 0, &str_res, &int_res);
-			if (rc2 == -1)
-				return pv_get_null(msg, param, res);
+			if (rc2 == 2)
+				goto out_free_null;
 			if (rc2 == 1) {
 				LM_DBG("NULL value in SQL db\n");
-				return pv_get_null(msg, param, res);
+				goto out_free_null;
 			}
 		}
 	}
 
 	if ((pv_name->c_entry->column_types & (one << pv_name->col_nr)) != 0) {
+		if (pkg_str_resize(&valbuff, str_res.len) != 0) {
+			LM_ERR("failed to alloc buffer\n");
+			goto out_free_null;
+		}
+
+		memcpy(valbuff.s, str_res.s, str_res.len);
+		valbuff.len = str_res.len;
+
 		res->flags = PV_VAL_STR;
-		res->rs.s = str_res.s;
+		res->rs.s = valbuff.s;
 		res->rs.len = str_res.len;
 	} else {
 		res->ri = int_res;
@@ -1679,7 +1693,12 @@ int pv_get_sql_cached_value(struct sip_msg *msg,  pv_param_t *param, pv_value_t
 		res->flags = PV_VAL_STR|PV_VAL_INT|PV_TYPE_INT;
 	}
 
+	pkg_free(cdb_res.s);
 	return 0;
+
+out_free_null:
+	pkg_free(cdb_res.s);
+	return pv_get_null(msg, param, res);
 }
 
 static void destroy(void)

ut.h

@@ -651,6 +651,25 @@ static inline char *pkg_strdup(const char *str)
 	return rval;
 }
 
+/* Extend the given buffer only if needed */
+static inline int pkg_str_resize(str *in, int size)
+{
+	char *p;
+
+	if (in->len < size) {
+		p = pkg_realloc(in->s, size);
+		if (!p) {
+			LM_ERR("oom\n");
+			return -1;
+		}
+
+		in->s = p;
+		in->len = size;
+	}
+
+	return 0;
+}
+
 /*
  * compare two str's
  */