Fix modelscan crash due to tag being NULL (#542)

* Fix modelscan crash due to tag being NULL

* Fix SCRIPTSCAN and add test

* Fix free string

* Fix call

Author: lantiga

src/model.c

@@ -119,7 +119,7 @@ static void *RAI_Model_RdbLoad(struct RedisModuleIO *io, int encver) {
     model->infokey =
         RAI_AddStatsEntry(stats_ctx, stats_keystr, RAI_MODEL, backend, stats_devicestr, stats_tag);
 
-    RedisModule_Free(stats_keystr);
+    RedisModule_FreeString(NULL, stats_keystr);
 
     return model;
 }

src/redisai.c

@@ -471,8 +471,9 @@ int RedisAI_ModelGet_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv,
     RedisModule_ReplyWithCString(ctx, mto->devicestr);
 
     RedisModule_ReplyWithCString(ctx, "tag");
-    RedisModuleString *empty_tag = RedisModule_CreateString(ctx, "", 0);
+    RedisModuleString *empty_tag = RedisModule_CreateString(NULL, "", 0);
     RedisModule_ReplyWithString(ctx, mto->tag ? mto->tag : empty_tag);
+    RedisModule_FreeString(NULL, empty_tag);
 
     RedisModule_ReplyWithCString(ctx, "batchsize");
     RedisModule_ReplyWithLongLong(ctx, (long)mto->opts.batchsize);
@@ -546,11 +547,13 @@ int RedisAI_ModelScan_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **argv
 
     RedisModule_ReplyWithArray(ctx, nkeys);
 
+    RedisModuleString *empty_tag = RedisModule_CreateString(NULL, "", 0);
     for (long long i = 0; i < nkeys; i++) {
         RedisModule_ReplyWithArray(ctx, 2);
         RedisModule_ReplyWithString(ctx, keys[i]);
-        RedisModule_ReplyWithString(ctx, tags[i]);
+        RedisModule_ReplyWithString(ctx, tags[i] ? tags[i] : empty_tag);
     }
+    RedisModule_FreeString(NULL, empty_tag);
 
     RedisModule_Free(keys);
     RedisModule_Free(tags);
@@ -787,11 +790,13 @@ int RedisAI_ScriptScan_RedisCommand(RedisModuleCtx *ctx, RedisModuleString **arg
 
     RedisModule_ReplyWithArray(ctx, nkeys);
 
+    RedisModuleString *empty_tag = RedisModule_CreateString(NULL, "", 0);
     for (long long i = 0; i < nkeys; i++) {
         RedisModule_ReplyWithArray(ctx, 2);
         RedisModule_ReplyWithString(ctx, keys[i]);
-        RedisModule_ReplyWithString(ctx, tags[i]);
+        RedisModule_ReplyWithString(ctx, tags[i] ? tags[i] : empty_tag);
     }
+    RedisModule_FreeString(NULL, empty_tag);
 
     RedisModule_Free(keys);
     RedisModule_Free(tags);

tests/flow/tests_pytorch.py

@@ -859,7 +859,7 @@ def test_pytorch_modelscan_scriptscan(env):
     ret = con.execute_command('AI.MODELSET', 'm1', 'TORCH', DEVICE, 'TAG', 'm:v1', 'BLOB', model_pb)
     env.assertEqual(ret, b'OK')
 
-    ret = con.execute_command('AI.MODELSET', 'm2', 'TORCH', DEVICE, 'TAG', 'm:v1', 'BLOB', model_pb)
+    ret = con.execute_command('AI.MODELSET', 'm2', 'TORCH', DEVICE, 'BLOB', model_pb)
     env.assertEqual(ret, b'OK')
 
     script_filename = os.path.join(test_data_path, 'script.txt')
@@ -870,7 +870,7 @@ def test_pytorch_modelscan_scriptscan(env):
     ret = con.execute_command('AI.SCRIPTSET', 's1', DEVICE, 'TAG', 's:v1', 'SOURCE', script)
     env.assertEqual(ret, b'OK')
 
-    ret = con.execute_command('AI.SCRIPTSET', 's2', DEVICE, 'TAG', 's:v1', 'SOURCE', script)
+    ret = con.execute_command('AI.SCRIPTSET', 's2', DEVICE, 'SOURCE', script)
     env.assertEqual(ret, b'OK')
 
     ensureSlaveSynced(con, env)