diff --git a/redis.conf b/redis.conf index d2eae1af2..1b79e09ef 100644 --- a/redis.conf +++ b/redis.conf @@ -392,23 +392,6 @@ auto-aof-rewrite-min-size 64mb # Set it to 0 or a negative value for unlimited execution without warnings. lua-time-limit 5000 -# By default variables in a Lua script are global, this means that a correct -# script must declare all the local variables explicitly using the 'local' -# keyword. Lua beginners are known to violate this rule, polluting the global -# namespace, or creating scripts that may fail under certain conditions, for -# this reason by default Redis installs a protection that will raise an error -# every time a script attempts to access a global variable that was not -# explicitly declared via global(). -# -# It's worth to note that normal Redis scripts should never use globals, but -# we don't entirely disable the possibility because from time to time crazy -# things in the right hands can be pretty powerful. -# -# Globals protection may result into a minor performance hint, so it is -# possible to disable the feature in production environments using the -# following configuration directive, or at runtime using CONFIG SET. -lua-protect-globals yes - ################################ REDIS CLUSTER ############################### # # Normal Redis instances can't be part of a Redis Cluster, only nodes that are diff --git a/src/config.c b/src/config.c index 5aa807f2d..8dffe2887 100644 --- a/src/config.c +++ b/src/config.c @@ -311,10 +311,6 @@ void loadServerConfigFromString(char *config) { server.cluster.configfile = zstrdup(argv[1]); } else if (!strcasecmp(argv[0],"lua-time-limit") && argc == 2) { server.lua_time_limit = strtoll(argv[1],NULL,10); - } else if (!strcasecmp(argv[0],"lua-protect-globals") && argc == 2) { - if ((server.lua_protect_globals = yesnotoi(argv[1])) == -1) { - err = "argument must be 'yes' or 'no'"; goto loaderr; - } } else if (!strcasecmp(argv[0],"slowlog-log-slower-than") && argc == 2) { @@ -556,16 +552,6 @@ void configSetCommand(redisClient *c) { } else if (!strcasecmp(c->argv[2]->ptr,"lua-time-limit")) { if (getLongLongFromObject(o,&ll) == REDIS_ERR || ll < 0) goto badfmt; server.lua_time_limit = ll; - } else if (!strcasecmp(c->argv[2]->ptr,"lua-protect-globals")) { - int enable = yesnotoi(o->ptr); - - if (enable == -1) goto badfmt; - if (enable == 0 && server.lua_protect_globals == 1) { - scriptingDisableGlobalsProtection(server.lua); - } else if (enable && server.lua_protect_globals == 0) { - scriptingEnableGlobalsProtection(server.lua); - } - server.lua_protect_globals = enable; } else if (!strcasecmp(c->argv[2]->ptr,"slowlog-log-slower-than")) { if (getLongLongFromObject(o,&ll) == REDIS_ERR) goto badfmt; server.slowlog_log_slower_than = ll; @@ -749,7 +735,6 @@ void configGetCommand(redisClient *c) { config_get_bool_field("daemonize", server.daemonize); config_get_bool_field("rdbcompression", server.rdb_compression); config_get_bool_field("activerehashing", server.activerehashing); - config_get_bool_field("lua-protect-globals", server.lua_protect_globals); /* Everything we can't handle with macros follows. */ diff --git a/src/redis.c b/src/redis.c index 089251b68..7ddeb886c 100644 --- a/src/redis.c +++ b/src/redis.c @@ -1068,7 +1068,6 @@ void initServerConfig() { server.lua_time_limit = REDIS_LUA_TIME_LIMIT; server.lua_client = NULL; server.lua_timedout = 0; - server.lua_protect_globals = 1; updateLRUClock(); resetServerSaveParams(); diff --git a/src/redis.h b/src/redis.h index bd4ef5a11..5a3d1a9c5 100644 --- a/src/redis.h +++ b/src/redis.h @@ -717,7 +717,6 @@ struct redisServer { int lua_timedout; /* True if we reached the time limit for script execution. */ int lua_kill; /* Kill the script if true. */ - int lua_protect_globals; /* If true globals must be declared */ /* Assert & bug reportign */ char *assert_failed; char *assert_file; @@ -1103,8 +1102,6 @@ void clusterPropagatePublish(robj *channel, robj *message); /* Scripting */ void scriptingInit(void); -void scriptingEnableGlobalsProtection(lua_State *lua); -void scriptingDisableGlobalsProtection(lua_State *lua); /* Git SHA1 */ char *redisGitSHA1(void); diff --git a/src/scripting.c b/src/scripting.c index 44ceb1e28..ae906c68c 100644 --- a/src/scripting.c +++ b/src/scripting.c @@ -416,10 +416,7 @@ void luaLoadLibraries(lua_State *lua) { * the creation of globals accidentally. * * It should be the last to be called in the scripting engine initialization - * sequence, because it may interact with creation of globals. - * Note that the function is designed to be called multiple times if needed - * without issues, because it is possible to enabled/disable globals protection - * at runtime with CONFIG SET. */ + * sequence, because it may interact with creation of globals. */ void scriptingEnableGlobalsProtection(lua_State *lua) { char *s[32]; sds code = sdsempty(); @@ -434,7 +431,7 @@ void scriptingEnableGlobalsProtection(lua_State *lua) { s[j++]=" if not mt.declared[n] and debug.getinfo(2) then\n"; s[j++]=" local w = debug.getinfo(2, \"S\").what\n"; s[j++]=" if w ~= \"main\" and w ~= \"C\" then\n"; - s[j++]=" error(\"assignment to undeclared global variable '\"..n..\"'\", 2)\n"; + s[j++]=" error(\"Script attempted to create global variable '\"..tostring(n)..\"'\", 2)\n"; s[j++]=" end\n"; s[j++]=" mt.declared[n] = true\n"; s[j++]=" end\n"; @@ -442,17 +439,10 @@ void scriptingEnableGlobalsProtection(lua_State *lua) { s[j++]="end\n"; s[j++]="mt.__index = function (t, n)\n"; s[j++]=" if debug.getinfo(2) and not mt.declared[n] and debug.getinfo(2, \"S\").what ~= \"C\" then\n"; - s[j++]=" error(\"global variable '\"..n..\"' is not declared\", 2)\n"; + s[j++]=" error(\"Script attempted to access unexisting global variable '\"..n..\"'\", 2)\n"; s[j++]=" end\n"; s[j++]=" return rawget(t, n)\n"; s[j++]="end\n"; - s[j++]="function global(...)\n"; - s[j++]=" local nargs = select(\"#\",...)\n"; - s[j++]=" for i = 1, nargs do\n"; - s[j++]=" local v = select(i,...)\n"; - s[j++]=" mt.declared[v] = true\n"; - s[j++]=" end\n"; - s[j++]="end\n"; s[j++]=NULL; for (j = 0; s[j] != NULL; j++) code = sdscatlen(code,s[j],strlen(s[j])); @@ -461,12 +451,6 @@ void scriptingEnableGlobalsProtection(lua_State *lua) { sdsfree(code); } -void scriptingDisableGlobalsProtection(lua_State *lua) { - char *s = "setmetatable(_G, nil)\n"; - luaL_loadbuffer(lua,s,strlen(s),"disable_strict_lua"); - lua_pcall(lua,0,0,0); -} - /* Initialize the scripting environment. * It is possible to call this function to reset the scripting environment * assuming that we call scriptingRelease() before. @@ -559,8 +543,7 @@ void scriptingInit(void) { /* Lua beginners ofter don't use "local", this is likely to introduce * subtle bugs in their code. To prevent problems we protect accesses * to global variables. */ - if (server.lua_protect_globals) - scriptingEnableGlobalsProtection(lua); + scriptingEnableGlobalsProtection(lua); server.lua = lua; }