From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp31.i.mail.ru (smtp31.i.mail.ru [94.100.177.91]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dev.tarantool.org (Postfix) with ESMTPS id 638B7469719 for ; Tue, 11 Feb 2020 11:46:18 +0300 (MSK) References: <20200210075707.86953-1-arkholga@tarantool.org> <20200210130823.GF1110@tarantool.org> From: Olga Arkhangelskaia Message-ID: Date: Tue, 11 Feb 2020 11:46:15 +0300 MIME-Version: 1.0 In-Reply-To: <20200210130823.GF1110@tarantool.org> Content-Type: text/plain; charset="utf-8"; format="flowed" Content-Transfer-Encoding: 8bit Content-Language: en-GB Subject: Re: [Tarantool-patches] [PATCH] json: fix silent change of global json settings List-Id: Tarantool development patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Nikita Pettik Cc: tarantool-patches@dev.tarantool.org Hi Nikita! Thanks for the review! I fixed all issues that you have pointed out. And pushed branch. 10.02.2020 16:08, Nikita Pettik пишет: > On 10 Feb 10:57, Olga Arkhangelskaia wrote: >> When json.decode is used with 2 arguments, 2nd argument seeps out to global >> json settings. Morover, > Nit: Moreover. > >> due to current serialier.cfg implementation it > -> serializer > >> remains invisible while checking settings by json.cfg. To prevent sucj > -> such > >> behaviour we stop writing to global serializer struct and use local one, >> to get one-time action. >> As was mention before json.cfg can not be trusted in this case, so to check that >> everything remained unchanged we call decode twice with and without 2nd >> argument. >> >> Closes #4761 > Note that there's no 'Closes #4761' label on your actual branch. > I guess you simply forgot to push updated branch. > >> --- >> + -- >> + -- gh-4761 json.decode silently changes global settings of json when called >> + -- with 2d parameter >> + -- >> + test:ok(pcall(serializer.decode,'{"1":{"b":{"c":1,"d":null}},"a":1}')) >> >> -- >> -- gh-3514: fix parsing integers with exponent in json >> diff --git a/third_party/lua-cjson/lua_cjson.c b/third_party/lua-cjson/lua_cjson.c >> index 3d25814f3..f855cbd80 100644 >> --- a/third_party/lua-cjson/lua_cjson.c >> +++ b/third_party/lua-cjson/lua_cjson.c >> @@ -1004,13 +1004,13 @@ static int json_decode(lua_State *l) >> luaL_argcheck(l, lua_gettop(l) == 2 || lua_gettop(l) == 1, 1, >> "expected 1 or 2 arguments"); >> >> + struct luaL_serializer *cfg = luaL_checkserializer(l); > Nit: I'd add a brief comment here (to avoid any confusions concerning > copying object on the stack): > > diff --git a/third_party/lua-cjson/lua_cjson.c b/third_party/lua-cjson/lua_cjson.c > index f855cbd80..c9c987c8c 100644 > --- a/third_party/lua-cjson/lua_cjson.c > +++ b/third_party/lua-cjson/lua_cjson.c > @@ -1006,6 +1006,14 @@ static int json_decode(lua_State *l) > > struct luaL_serializer *cfg = luaL_checkserializer(l); > struct luaL_serializer user_cfg = *cfg; > + /* > + * user_cfg is per-call local version of global cfg: it is > + * used if user passes custom options to :decode() method > + * as a separate arguments. In this case it is required > + * to avoid modifying global parameters. Life span of > + * user_cfg is restricted by the scope of :decode() so it > + * is enough to allocate it on the stack. > + */ > json.cfg = cfg; > if (lua_gettop(l) == 2) { > >> + struct luaL_serializer user_cfg = *cfg; >> + json.cfg = cfg; > What is more, you can avoid premature copying on the stack: > > @@ -1005,9 +1005,10 @@ static int json_decode(lua_State *l) > "expected 1 or 2 arguments"); > > struct luaL_serializer *cfg = luaL_checkserializer(l); > - struct luaL_serializer user_cfg = *cfg; > + struct luaL_serializer user_cfg; > json.cfg = cfg; > if (lua_gettop(l) == 2) { > + user_cfg = *cfg; > luaL_serializer_parse_options(l, &user_cfg); > lua_pop(l, 1); > json.cfg = &user_cfg; > >> if (lua_gettop(l) == 2) { >> - struct luaL_serializer *user_cfg = luaL_checkserializer(l); >> - luaL_serializer_parse_options(l, user_cfg); >> + luaL_serializer_parse_options(l, &user_cfg); Here is new diff diff --git a/third_party/lua-cjson/lua_cjson.c b/third_party/lua-cjson/lua_cjson.c index f855cbd80..5925e7e6f 100644 --- a/third_party/lua-cjson/lua_cjson.c +++ b/third_party/lua-cjson/lua_cjson.c @@ -1005,9 +1005,18 @@ static int json_decode(lua_State *l)                    "expected 1 or 2 arguments");      struct luaL_serializer *cfg = luaL_checkserializer(l); -    struct luaL_serializer user_cfg = *cfg; +    struct luaL_serializer user_cfg; +    /* +     * user_cfg is per-call local version of global cfg: it is +     * used if user passes custom options to :decode() method +     * as a separate arguments. In this case it is required +     * to avoid modifying global parameters. Life span of +     * user_cfg is restricted by the scope of :decode() so it +     * is enough to allocate it on the stack. +     */      json.cfg = cfg;      if (lua_gettop(l) == 2) { +        user_cfg = *cfg;          luaL_serializer_parse_options(l, &user_cfg);          lua_pop(l, 1);          json.cfg = &user_cfg;