diff --git a/redis.conf b/redis.conf
index d2eae1af..1b79e09e 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 5aa807f2..8dffe288 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 089251b6..7ddeb886 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 bd4ef5a1..5a3d1a9c 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 44ceb1e2..ae906c68 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;
}