バグ バグLuaの各リリースで見つかったバグのリストを、4.0以降で掲載しています。
各エントリには、バグを示す最小限の例と、利用可能な場合はパッチまたは解決策が含まれています。より大きな修正は、LuaのGitHubリポジトリに掲載されています。これは不定期にミラーリングされます。Luaのすべてのリリースでは、特に記載がない限り、以前のリリースにリストされているすべてのバグが修正されています。新しいリリースで見つかった一部のバグは、古いリリースに存在していた可能性があります。
バグを報告したい場合は、まずこちらをお読みください。
例
-- You must have the locale 'km_KH.UTF-8' installed
assert(os.setlocale("km_KH.UTF-8"))
local A = "\u{17A4}"
local B = "\u{17A2}\u{17B6}"
print(string.rep(B, 100000) .. "\0" <= string.rep(A, 100000) .. "\0")
例
/* The following program prints "Call hook: Lua" twice, while it
should print that only once. */
#include <stdio.h>
#include "lua.h"
#include "lauxlib.h"
static void hook (lua_State *L, lua_Debug *ar) {
if (ar->event == LUA_HOOKCALL) { /* call hook? */
lua_getinfo(L, "S", ar);
printf("Call hook: %s\n", ar->what);
}
else /* count hook */
lua_yield(L, 0);
}
int main (void) {
lua_State *L = luaL_newstate();
lua_State *l = lua_newthread(L);
luaL_loadstring(l, "(function(x) end)()");
lua_sethook(l, hook, LUA_MASKCOUNT | LUA_MASKCALL, 1);
int nres;
while (lua_resume(l, NULL, 0, &nres) == LUA_YIELD) { }
lua_close(L);
}
例
-- error should be at line 3 foo ( 0 ) --> lua: temp:2: attempt to call a nil value (global 'foo')
例
-- This code takes forever to run, and eventually it crashes
local a = {"local d = 1; d = d * _G"}
for i = 2, 1e7 do a[i] = "._G" end
a = table.concat(a)
a = load(a)
print(a())
例
a = {_ENV = {}}
print(a._ENV.x + 1)
--> attempt to perform arithmetic on a nil value (global 'x')
例
-- seg.faults in 32-bit machines local a = 'Name' for b = -1000, 0 do a = a .. '____________' .. a .. '____________' .. a .. a .. '____________' end
例
*** yieldhook.c:
#include "lua.h"
#include "lauxlib.h"
#include "string.h"
static void hookf (lua_State *L, lua_Debug *ar) {
if (ar->currentline == 6)
lua_yield(L, 0);
}
static int db_sethook (lua_State *L) {
lua_sethook(L, hookf, LUA_MASKLINE, 0);
return 0;
}
int luaopen_yieldhook(lua_State *L) {
static luaL_Reg l[] = {
{ "sethook", db_sethook },
{ NULL, NULL },
};
luaL_checkversion(L);
luaL_newlib(L, l);
return 1;
}
*** test.lua:
local yieldhook = require 'yieldhook'
local function test()
local a1 = 1
local a2 = 2
local a3 = 3
local a4 = 4
return a1 + a2 + a3 + a4
end
local function run()
yieldhook.sethook(coroutine.running())
return test()
end
local co = coroutine.create(run)
coroutine.resume(co)
local name
local i = 1
for i = 1, 20 do
local name, value = debug.getlocal(co, 0, i)
if name == nil then break end
i = i + 1
print(name, value)
end
result:
a1 1
a2 2
--a3 3 is lost
例
-- Lua compiled with assertions on local _ENV <const> = 0 X=0
例
local _ = {"1","2","3","4","5","6","7","8","9","10","11","12",
"13","14","15","16","17","18","19","20","21","22","23","24","25","26",
"27","28","29","30","31","32","33","34","35","36","37","38",
"39","40","41","42","43","44","45","46","47","48","49","50",
"51","52","53","54","55","56","57","58","59","60","61","62","63","64",
"65","66","67","68","69","70","71","72","73","74","75","76","77","78",
"79","80","81","82","83","84","85","86","87","88","89","90","91","92",
"93","94","95","96","97","98","99","100","101","102","103","104",
"105","106","107","108","109","110","111","112","113","114",
"115","116","117","118","119","120","121","122","123","124",
"125","126","127","128","129","130","131","132","133","134",
"135","136","137","138","139","140","141","142","143","144",
"145","146","147","148","149","150","151","152","153","154",
"155","156","157","158","159","160","161","162","163","164",
"165","166","167","168","169","170","171","172","173","174",
"175","176","177","178","179","180","181","182","183","184",
"185","186","187","188","189","190","191","192","193","194",
"195","196","197","198","199","200","201","202","203","204",
"205","206","207","208","209","210","211","212","213","214",
"215","216","217","218","219","220","221","222","223","224",
"225","226","227","228","229","230","231","232","233","234",
"235","236","237","238","239","240","241","242","243","244",
"245","246","247","248","249","250","251","252","253","254",
"255","256", }
-- should print 3, but prints 2
print (1 | (2 or 3))
例
print(
xpcall((0),
function(...)
local f
if d[print(print(print(print(t[...]))))] then
end
end
)
)
例
-- (needs test library)
-- reduce stack size
collectgarbage(); collectgarbage(); collectgarbage()
-- force a stack reallocation
local function loop (n)
if n < 400 then loop(n + 1) end
end
local o = setmetatable({}, {__close = function () loop(0) end})
local script = [[toclose 2; settop 1; return 1]]
assert(T.testC(script, o) == script)
例
local closed = false
local o1 = setmetatable({}, {__close=function() closed = true end})
local function test()
for k, v in next, {}, nil, o1 do
local function f() return k end -- just to use 'k'
break
end
assert(closed) -- should be closed here
end
test()
例
-- the following code should raise an error
for pos, cp in utf8.codes('in\xbfvalid') do
print(pos, cp)
end
例
-- Depending on the size of your C stack, you may need to increase the
-- limit of the loop.
local coro
for i = 1, 1e5 do
local previous = coro
coro = coroutine.create(function()
local cc <close> = setmetatable({}, {__close=function()
if previous then
assert(coroutine.close(previous))
end
end})
coroutine.yield()
end)
assert(coroutine.resume(coro))
end
print(coroutine.close(coro))
例
local a = 0 local b = 1 print(b // a) --> lua: temp:1: attempt to divide by zero
例
-- Binary files have different formats in different versions. This -- example is specific for Lua 5.4. local code = "\x1b\x4c\x75\x61\x54\x00\x19\x93\x0d\x0a\x1a\x0a\x04\x08\x08\x78\x56\z \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x28\x77\x40\x00\x86\x40\z \x74\x65\x6d\x70\x81\x81\x01\x00\x02\x82\x48\x00\x02\x00\xc7\x00\x01\z \x00\x80\x80\x80\x82\x00\x00\x80\x81\x82\x78\x80\x82\x81\x86\x40\x74\z \x65\x6d\x70" assert(load(code))
例
local function iter ()
return function () return true end, 0, 0,
setmetatable({}, {__close = print})
end
local function tail() print("tail") end
local function foo ()
for k in iter() do return tail() end
end
foo()
パッチ
lvm.c:
@@ -1156,8 +1156,10 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
Instruction i; /* instruction being executed */
StkId ra; /* instruction's A register */
vmfetch();
-// low-level line tracing for debugging Lua
-// printf("line: %d\n", luaG_getfuncline(cl->p, pcRel(pc, cl->p)));
+ #if 0
+ /* low-level line tracing for debugging Lua */
+ printf("line: %d\n", luaG_getfuncline(cl->p, pcRel(pc, cl->p)));
+ #endif
lua_assert(base == ci->func + 1);
lua_assert(base <= L->top && L->top < L->stack_last);
/* invalidate top for instructions not expecting it */
例
-- The final 'print' should print nothing, as the 'print' inside 'test'
-- returns nothing.
local function test()
local x <close> = setmetatable({}, {
__close = coroutine.yield
})
return print("Return")
end
local c = coroutine.wrap(test)
c() -- runs until '__close'
print(c()) -- runs until end
パッチ
lvm.c:
@@ -847,10 +847,19 @@ void luaV_finishOp (lua_State *L) {
luaV_concat(L, total); /* concat them (may yield again) */
break;
}
- case OP_CLOSE: case OP_RETURN: { /* yielded closing variables */
+ case OP_CLOSE: { /* yielded closing variables */
ci->u.l.savedpc--; /* repeat instruction to close other vars. */
break;
}
+ case OP_RETURN: { /* yielded closing variables */
+ StkId ra = base + GETARG_A(inst);
+ /* correct top to signal correct number of returns (in case the
+ return is "in top" */
+ L->top = ra + ci->u2.nres;
+ /* repeat instruction to close other vars. and complete the return */
+ ci->u.l.savedpc--;
+ break;
+ }
default: {
/* only these other opcodes can yield */
lua_assert(op == OP_TFORCALL || op == OP_CALL ||
@@ -1672,6 +1681,7 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
n = cast_int(L->top - ra); /* get what is available */
savepc(ci);
if (TESTARG_k(i)) { /* may there be open upvalues? */
+ ci->u2.nres = n; /* save number of returns */
if (L->top < ci->top)
L->top = ci->top;
luaF_close(L, base, CLOSEKTOP, 1);
例
local x<const> = {}
function x() end -- should raise an error
print(x)
例
-- (must be run in interactive mode)
-- Both prints should show the same result
> debug.debug()
lua_debug> x = setmetatable({}, {__name="TABLE"})
lua_debug> print(x)
lua_debug> error(x)
パッチ
lauxlib.c:
@@ -881,6 +881,7 @@ LUALIB_API lua_Integer luaL_len (lua_State *L, int idx) {
LUALIB_API const char *luaL_tolstring (lua_State *L, int idx, size_t *len) {
+ idx = lua_absindex(L,idx);
if (luaL_callmeta(L, idx, "__tostring")) { /* metafield? */
if (!lua_isstring(L, -1))
luaL_error(L, "'__tostring' must return a string");
例
-- Lua compiled in gcc with option '-fsanitize=undefined' print(1 >> math.mininteger)
パッチ
lvm.c:
@@ -766,7 +766,7 @@ lua_Number luaV_modf (lua_State *L, lua_Number m, lua_Number n) {
/*
** Shift left operation. (Shift right just negates 'y'.)
*/
-#define luaV_shiftr(x,y) luaV_shiftl(x,-(y))
+#define luaV_shiftr(x,y) luaV_shiftl(x,intop(-, 0, y))
lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) {
if (y < 0) { /* shift right? */
例
local function func() pcall(1) coroutine.wrap(func)() end func()
例
-- Must be run with assertions on, valgrind, or sanitizer
co = coroutine.wrap(
function()
local x <close> = setmetatable(
{}, {__close = function() pcall(co) end}
)
error()
end
)
co()
例
-- The following chunk may segfault
function v (...)
return os.exit(0, true)
end
local x <close> = setmetatable({}, {__close = error})
v()
例
function func1 ()
local f = setmetatable({}, {__gc = function () collectgarbage("step") end})
collectgarbage("step" , 1)
end
for i = 0,1000 do
setmetatable({}, {__gc = func1})
end
例
local x = {}; for i=1, 2000 do x[i] = i end
local function f() end
local function g() return f(table.unpack(x)) end
collectgarbage("step")
setmetatable({}, {__gc = 1})
g()
例
-- The following code illustrates the problem. If finalizer 3 calls
-- a function from a dynamically loaded C module, the C module
-- will be closed by the time the function is called, generating
-- a seg. fault.
-- should be called last
print("creating 1")
setmetatable({}, {__gc = function () print(1) end})
print("creating 2")
setmetatable({}, {__gc = function ()
print("2")
print("creating 3")
setmetatable({}, {__gc = function () print(3) end})
os.exit(1, true)
end})
例
nan = 0/0
t = {nan, nan, 20, 10}
table.sort(t)
print(table.concat(t, ", "))
--> -nan, 20, -nan, 10
パッチ：マニュアルは誤解を招きやすいです。ソート関数が部分順序を定義することは必要ですが、十分ではありません。
例
-- with Lua compiled with option LUA_USE_APICHECK debug.getinfo(0, ">")
パッチ
ldblib.c:
@@ -152,6 +152,7 @@ static int db_getinfo (lua_State *L) {
lua_State *L1 = getthread(L, &arg);
const char *options = luaL_optstring(L, arg+2, "flnSrtu");
checkstack(L, L1, 3);
+ luaL_argcheck(L, options[0] != '>', arg + 2, "invalid option '>'");
if (lua_isfunction(L, arg + 1)) { /* info about a function? */
options = lua_pushfstring(L, ">%s", options); /* add '>' to 'options' */
lua_pushvalue(L, arg + 1); /* move function to 'L1' stack */
例
-- the following call gives an error message with a wrong index
table.concat({}, "", math.maxinteger, math.maxinteger)
パッチ
ltablib.c:
@@ -146,7 +146,7 @@ static int tmove (lua_State *L) {
static void addfield (lua_State *L, luaL_Buffer *b, lua_Integer i) {
lua_geti(L, 1, i);
if (!lua_isstring(L, -1))
- luaL_error(L, "invalid value (%s) at index %d in table for 'concat'",
+ luaL_error(L, "invalid value (%s) at index %I in table for 'concat'",
luaL_typename(L, -1), i);
luaL_addvalue(b);
}
例: このバグは、フラットメモリアーキテクチャではおそらく障害を引き起こさないでしょう。gccオプション'-fsanitize=pointer-subtract' (およびそれが動作するために必要なもの) を付けてLuaをコンパイルし、次のコードを実行することで、強制的に発生させることができます。
print(setmetatable({}, {__index = 4}).x)
例
t = {}
t["no" .. "ref1"] = 1
t["no" .. "ref2"] = 2
for k, v in pairs(t) do
t[k] = nil
print(k, v)
collectgarbage("collect")
end
例
-- run this code with some memory checker, such as valgrind
-- or gcc's option -fsanitize=address
local A = {}
A[1] = false -- create an old anchor for an object
-- obj finalizer
local function gcf (obj)
A[1] = obj -- anchor object
obj = nil -- remove it from the stack
collectgarbage("step", 0) -- do a young collection
print(getmetatable(A[1]).x) -- metatable was collected!
end
collectgarbage() -- make A old
local obj = {} -- create a new object
collectgarbage("step", 0) -- make it a survival
setmetatable(obj, {__gc = gcf}) -- create its metatable
obj = nil -- clear object
collectgarbage("step", 0) -- will call obj's finalizer
パッチ
lgc.c:
@@ -1140,7 +1140,7 @@ static void finishgencycle (lua_State *L, global_State *g) {
static void youngcollection (lua_State *L, global_State *g) {
GCObject **psurvival; /* to point to first non-dead survival object */
lua_assert(g->gcstate == GCSpropagate);
- markold(g, g->survival, g->reallyold);
+ markold(g, g->allgc, g->reallyold);
markold(g, g->finobj, g->finobjrold);
atomic(L);
例
local lim = 1000
local function stack (n)
if n > 0 then return stack(n - 1) + 1
else coroutine.wrap(function ()
stack(lim)
end)()
end
end
print(xpcall(stack, function () return "ok" end, lim))
パッチ
ldo.c:
@@ -674,7 +674,7 @@ LUA_API int lua_resume (lua_State *L, lua_State *from, int nargs,
if (from == NULL)
L->nCcalls = CSTACKTHREAD;
else /* correct 'nCcalls' for this thread */
- L->nCcalls = getCcalls(from) + from->nci - L->nci - CSTACKCF;
+ L->nCcalls = getCcalls(from) - L->nci - CSTACKCF;
if (L->nCcalls <= CSTACKERR)
return resume_error(L, "C stack overflow", nargs);
luai_userstateresume(L, nargs);
例
-- must compile Lua with option -DHARDMEMTESTS, to force -- emergency collections local s = string.dump(function () local x, y, z return function () return x + y + z end end) for i = 1, #s - 1 do assert(not load(string.sub(s, 1, i))) end
パッチ
lundump.c:
@@ -205,8 +205,9 @@ static void loadUpvalues (LoadState *S, Proto *f) {
n = loadInt(S);
f->upvalues = luaM_newvectorchecked(S->L, n, Upvaldesc);
f->sizeupvalues = n;
- for (i = 0; i < n; i++) {
+ for (i = 0; i < n; i++)
f->upvalues[i].name = NULL;
+ for (i = 0; i < n; i++) {
f->upvalues[i].instack = loadByte(S);
f->upvalues[i].idx = loadByte(S);
f->upvalues[i].kind = loadByte(S);
例: http://lua-users.org/lists/lua-l/2020-07/msg00053.htmlを参照してください。
パッチ
ldo.c:
@@ -466,13 +466,13 @@ void luaD_call (lua_State *L, StkId func, int nresults) {
f = fvalue(s2v(func));
Cfunc: {
int n; /* number of returns */
- CallInfo *ci = next_ci(L);
+ CallInfo *ci;
checkstackp(L, LUA_MINSTACK, func); /* ensure minimum stack size */
+ L->ci = ci = next_ci(L);
ci->nresults = nresults;
ci->callstatus = CIST_C;
ci->top = L->top + LUA_MINSTACK;
ci->func = func;
- L->ci = ci;
lua_assert(ci->top <= L->stack_last);
if (L->hookmask & LUA_MASKCALL) {
int narg = cast_int(L->top - func) - 1;
@@ -486,18 +486,18 @@ void luaD_call (lua_State *L, StkId func, int nresults) {
break;
}
case LUA_VLCL: { /* Lua function */
- CallInfo *ci = next_ci(L);
+ CallInfo *ci;
Proto *p = clLvalue(s2v(func))->p;
int narg = cast_int(L->top - func) - 1; /* number of real arguments */
int nfixparams = p->numparams;
int fsize = p->maxstacksize; /* frame size */
checkstackp(L, fsize, func);
+ L->ci = ci = next_ci(L);
ci->nresults = nresults;
ci->u.l.savedpc = p->code; /* starting point */
ci->callstatus = 0;
ci->top = func + 1 + fsize;
ci->func = func;
- L->ci = ci;
for (; narg < nfixparams; narg++)
setnilvalue(s2v(L->top++)); /* complete missing arguments */
lua_assert(ci->top <= L->stack_last);
例: http://lua-users.org/lists/lua-l/2020-07/msg00054.htmlを参照してください。
パッチ
ldo.h: @@ -44,7 +44,7 @@ /* macro to check stack size and GC */ #define checkstackGC(L,fsize) \ - luaD_checkstackaux(L, (fsize), (void)0, luaC_checkGC(L)) + luaD_checkstackaux(L, (fsize), luaC_checkGC(L), (void)0) /* type of protected functions, to be ran by 'runprotected' */
例: http://lua-users.org/lists/lua-l/2020-07/msg00078.html。
パッチ
lvm.c:
@@ -1104,7 +1104,7 @@ void luaV_finishOp (lua_State *L) {
#define checkGC(L,c) \
- { luaC_condGC(L, L->top = (c), /* limit of live values */ \
+ { luaC_condGC(L, (savepc(L), L->top = (c)), \
updatetrap(ci)); \
luai_threadyield(L); }
@@ -1792,8 +1792,7 @@ void luaV_execute (lua_State *L, CallInfo *ci) {
vmbreak;
}
vmcase(OP_VARARGPREP) {
- luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p);
- updatetrap(ci);
+ ProtectNT(luaT_adjustvarargs(L, GETARG_A(i), ci, cl->p));
if (trap) {
luaD_hookcall(L, ci);
L->oldpc = pc + 1; /* next opcode will be seen as a "new" line */
例: (システム依存)
パッチ
liolib.c:
@@ -279,6 +279,8 @@ static int io_popen (lua_State *L) {
const char *filename = luaL_checkstring(L, 1);
const char *mode = luaL_optstring(L, 2, "r");
LStream *p = newprefile(L);
+ luaL_argcheck(L, ((mode[0] == 'r' || mode[0] == 'w') && mode[1] == '\0'),
+ 2, "invalid mode");
p->f = l_popen(L, filename, mode);
p->closef = &io_pclose;
return (p->f == NULL) ? luaL_fileresult(L, 0, filename) : 1;
例
-- run this code under valgrind. (Error depends on details of dynamic
-- addresses.)
function foo ()
local f = load[[io.write('+');
for i = 1, 10000 do local a = {}; debug.sethook(nil) end
io.write'-']]
local u = setmetatable({},
{__gc = assert(load[[debug.sethook(print, "l");
error('err');
]])})
u = nil
f()
end
for i = 1, 200 do
foo()
end
パッチ
lgc.c:
@@ -856,6 +856,8 @@ static void GCTM (lua_State *L) {
if (unlikely(status != LUA_OK)) { /* error while running __gc? */
luaE_warnerror(L, "__gc metamethod");
L->top--; /* pops error object */
+ if (isLua(L->ci))
+ L->oldpc = L->ci->u.l.savedpc; /* update 'oldpc' */
}
}
}
例
function errfunc () return 10 + xpcall(nil, errfunc) end coroutine.resume(coroutine.create(function() xpcall(nil, errfunc) end))
例
-- The following chunk, under a memory checker like valgrind,
-- produces a memory access violation.
local old = {10}
collectgarbage() -- make 'old' old
local co = coroutine.create(
function ()
local x = nil
local f = function ()
return x[1]
end
x = coroutine.yield(f)
coroutine.yield()
end
)
local _, f = coroutine.resume(co) -- create closure over x in thread
collectgarbage("step", 0) -- make upvalue a survival
old[1] = {"hello"} -- 'old' go to grayagain as 'touched1'
coroutine.resume(co, {123}) -- its value will be new
co = nil
-- next minor collection hits the barrier between upvalue and its
-- conent while sweeping the thread. This will mix the lists 'gray'
-- and 'grayagain' and will remove 'old' from 'grayagain'.
collectgarbage("step", 0)
assert(f() == 123 and old[1][1] == "hello") -- still ok
collectgarbage("step", 0) -- run the collector once more
-- now, as 'old' was not in 'grayagain', 'old[1]' was deleted
assert(f() == 123 and old[1][1] == "hello")
例
print(debug.getlocal(1, 2^31))
例
local function foo () local a = 1 local b = 2 local c = 3 end local s = load(string.dump(foo, true)) local line debug.sethook(function (e, l) line = l end, "l"); s(); debug.sethook(nil) print(line)
例
-- run this code under some memory checker
local function myload (s)
return load(function ()
if s == "" then return nil
else
local c = string.sub(s, 1, 1)
s = string.sub(s, 2)
collectgarbage()
return c
end
end)
end
local y = string.dump(function ()
return '01234567890123456789012345678901234567890123456789'
end)
y = myload(y)
assert(y() == '01234567890123456789012345678901234567890123456789')
これはLua 5.3の最後のリリースでした。後で報告されたバグは、おそらくLua 5.4で修正されています。
パッチ
src/Makefile: @@ -104,2 +104,2 @@ freebsd: - $(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX -DLUA_USE_READLINE -I/usr/include/edit" SYSLIBS="-Wl,-E -ledit" CC="cc" + $(MAKE) $(ALL) SYSCFLAGS="-DLUA_USE_LINUX -I/usr/include/edit" SYSLIBS="-Wl,-E -ledit" CC="cc"
パッチ
Makefile: @@ -49 +49 @@ -R= $V.4 +R= $V.5
例
local eqs = string.rep("=", 0x3ffffffe)
local code = "return [" .. eqs .. "[a]" .. eqs .. "]"
print(#assert(load(code))())
例
-- the next code may crash the machine
f=load(function() end)
interesting={}
interesting[0]=string.rep("A",512)
debug.upvaluejoin(f,1,f,1)
パッチ
lapi.c: @@ -1289,6 +1289,8 @@ LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1, LClosure *f1; UpVal **up1 = getupvalref(L, fidx1, n1, &f1); UpVal **up2 = getupvalref(L, fidx2, n2, NULL); + if (*up1 == *up2) + return; luaC_upvdeccount(L, *up1); *up1 = *up2; (*up1)->refcount++;
例
-- should print 32323232..., but prints only '3' if true then goto LBL ::loop:: print(2) ::LBL:: print(3) goto loop end
パッチ
lparser.c:
@@ -1392,7 +1392,7 @@
luaK_goiffalse(ls->fs, &v); /* will jump to label if condition is true */
enterblock(fs, &bl, 0); /* must enter block before 'goto' */
gotostat(ls, v.t); /* handle goto/break */
- skipnoopstat(ls); /* skip other no-op statements */
+ while (testnext(ls, ';')) {} /* skip semicolons */
if (block_follow(ls, 0)) { /* 'goto' is the entire block? */
leaveblock(fs);
return; /* and that is it */
例
-- crashes if machine has enough memory
local t = {}
for i = 1, 0x7fffffff do
t[i] = i
end
パッチ
ltable.c:
@@ -223,7 +223,9 @@
unsigned int na = 0; /* number of elements to go to array part */
unsigned int optimal = 0; /* optimal size for array part */
/* loop while keys can fill more than half of total size */
- for (i = 0, twotoi = 1; *pna > twotoi / 2; i++, twotoi *= 2) {
+ for (i = 0, twotoi = 1;
+ twotoi > 0 && *pna > twotoi / 2;
+ i++, twotoi *= 2) {
if (nums[i] > 0) {
a += nums[i];
if (a > twotoi/2) { /* more than half elements present? */
例
-- on a machine with enough memory
local t = {}
for i = 1, 2147483681 do
t[i] = i
end
print(#t)
パッチ
ltable.h:
@@ -56,3 +56,3 @@
LUAI_FUNC int luaH_next (lua_State *L, Table *t, StkId key);
-LUAI_FUNC int luaH_getn (Table *t);
+LUAI_FUNC lua_Unsigned luaH_getn (Table *t);
ltable.c:
@@ -614,4 +614,4 @@
-static int unbound_search (Table *t, unsigned int j) {
- unsigned int i = j; /* i is zero or a present index */
+static lua_Unsigned unbound_search (Table *t, lua_Unsigned j) {
+ lua_Unsigned i = j; /* i is zero or a present index */
j++;
@@ -620,3 +620,3 @@
i = j;
- if (j > cast(unsigned int, MAX_INT)/2) { /* overflow? */
+ if (j > l_castS2U(LUA_MAXINTEGER) / 2) { /* overflow? */
/* table was built with bad purposes: resort to linear search */
@@ -630,3 +630,3 @@
while (j - i > 1) {
- unsigned int m = (i+j)/2;
+ lua_Unsigned m = (i+j)/2;
if (ttisnil(luaH_getint(t, m))) j = m;
@@ -642,3 +642,3 @@
*/
-int luaH_getn (Table *t) {
+lua_Unsigned luaH_getn (Table *t) {
unsigned int j = t->sizearray;
例
function test()
bob.joe.larry = 23
end
-- memory will grow steadly
for i = 1, math.huge do
pcall(test)
if i % 100000 == 0 then
io.write(collectgarbage'count'*1024, "\n")
end
end
パッチ
ldebug.c: @@ -653,6 +653,7 @@ CallInfo *ci = L->ci; const char *msg; va_list argp; + luaC_checkGC(L); /* error message uses memory */ va_start(argp, fmt); msg = luaO_pushvfstring(L, fmt, argp); /* format message */ va_end(argp);
例
-- The following chunk, under a memory checker like valgrind, produces a memory access violation.
local a = setmetatable({}, {__mode = 'kv'})
a['ABCDEFGHIJKLMNOPQRSTUVWXYZ' .. 'abcdefghijklmnopqrstuvwxyz'] = {}
a[next(a)] = nil
collectgarbage()
print(a['BCDEFGHIJKLMNOPQRSTUVWXYZ' .. 'abcdefghijklmnopqrstuvwxyz'])
パッチ
lgc.c:
@@ -643,8 +643,9 @@
for (n = gnode(h, 0); n < limit; n++) {
if (!ttisnil(gval(n)) && (iscleared(g, gkey(n)))) {
setnilvalue(gval(n)); /* remove value ... */
- removeentry(n); /* and remove entry from table */
}
+ if (ttisnil(gval(n))) /* is entry empty? */
+ removeentry(n); /* remove entry from table */
}
}
}
lua_pushcclosure は、n がゼロの場合、ガベージコレクタを呼び出すべきではありません。パッチ
lapi.c:
@@ -533,6 +533,7 @@
lua_lock(L);
if (n == 0) {
setfvalue(L->top, fn);
+ api_incr_top(L);
}
else {
CClosure *cl;
@@ -546,9 +547,9 @@
/* does not need barrier because closure is white */
}
setclCvalue(L, L->top, cl);
+ api_incr_top(L);
+ luaC_checkGC(L);
}
- api_incr_top(L);
- luaC_checkGC(L);
lua_unlock(L);
}
例
local a = {x = 1, y = 1, z = 1}
a[1] = 10 -- goes to the hash part (which has 4 slots)
print(a[1]) --> 10
-- assume that the 2nd memory allocation from now fails
pcall(rawset, a, 2, 20) -- forces a rehash
-- a[1] now exists both in the array part (because the array part
-- grew) and in the hash part (because the allocation of the hash
-- part failed, keeping it as it was).
-- This makes the following traversal goes forever...
for k,v in pairs(a) do print(k,v) end
パッチ
ltable.c:
@@ -332,17 +332,34 @@
}
+typedef struct {
+ Table *t;
+ unsigned int nhsize;
+} AuxsetnodeT;
+
+
+static void auxsetnode (lua_State *L, void *ud) {
+ AuxsetnodeT *asn = cast(AuxsetnodeT *, ud);
+ setnodevector(L, asn->t, asn->nhsize);
+}
+
+
void luaH_resize (lua_State *L, Table *t, unsigned int nasize,
unsigned int nhsize) {
unsigned int i;
int j;
+ AuxsetnodeT asn;
unsigned int oldasize = t->sizearray;
int oldhsize = allocsizenode(t);
Node *nold = t->node; /* save old hash ... */
if (nasize > oldasize) /* array part must grow? */
setarrayvector(L, t, nasize);
/* create new hash part with appropriate size */
- setnodevector(L, t, nhsize);
+ asn.t = t; asn.nhsize = nhsize;
+ if (luaD_rawrunprotected(L, auxsetnode, &asn) != LUA_OK) { /* mem. error? */
+ setarrayvector(L, t, oldasize); /* array back to its original size */
+ luaD_throw(L, LUA_ERRMEM); /* rethrow memory error */
+ }
if (nasize < oldasize) { /* array part must shrink? */
t->sizearray = nasize;
/* re-insert elements from vanishing slice */
例
-- the next loop will probably crash the interpreter repeat until load "for _ in _,_,_,_ do local function _() end"
パッチ
lparser.c:
@@ -323,6 +323,8 @@
luaK_nil(fs, reg, extra);
}
}
+ if (nexps > nvars)
+ ls->fs->freereg -= nexps - nvars; /* remove extra values */
}
@@ -1160,11 +1162,8 @@
int nexps;
checknext(ls, '=');
nexps = explist(ls, &e);
- if (nexps != nvars) {
+ if (nexps != nvars)
adjust_assign(ls, nvars, nexps, &e);
- if (nexps > nvars)
- ls->fs->freereg -= nexps - nvars; /* remove extra values */
- }
else {
luaK_setoneret(ls->fs, &e); /* close last expression */
luaK_storevar(ls->fs, &lh->v, &e);
os.dateの書式をチェックすると、書式文字列を読み飛ばす可能性があります。例: このバグは、通常のコンパイラでは発生しないようです。差が見つかった後にメモリの読み取りを続ける「インターセプター」'memcmp'関数が必要です。
パッチ
loslib.c:
263c263,264
< for (option = LUA_STRFTIMEOPTIONS; *option != '\0'; option += oplen) {
---
> int convlen = (int)strlen(conv);
> for (option = LUA_STRFTIMEOPTIONS; *option != '\0' && oplen <= convlen; option += oplen) {
例: http://lua-users.org/lists/lua-l/2016-07/msg00303.html を参照してください。
パッチ
lcode.c:
@@ -1018,8 +1018,8 @@
*/
static void codebinexpval (FuncState *fs, OpCode op,
expdesc *e1, expdesc *e2, int line) {
- int rk1 = luaK_exp2RK(fs, e1); /* both operands are "RK" */
- int rk2 = luaK_exp2RK(fs, e2);
+ int rk2 = luaK_exp2RK(fs, e2); /* both operands are "RK" */
+ int rk1 = luaK_exp2RK(fs, e1);
freeexps(fs, e1, e2);
e1->u.info = luaK_codeABC(fs, op, 0, rk1, rk2); /* generate opcode */
e1->k = VRELOCABLE; /* all those operations are relocatable */
例
-- with C assertions on A = coroutine.running() B = coroutine.create(function() coroutine.resume(A) end) coroutine.resume(B) -- or A = coroutine.wrap(function() pcall(A, _) end) A()
例
local mt = {}
mt.__newindex = mt
local t = setmetatable({}, mt)
t[1] = 1 -- will segfault on some machines
パッチ
lvm.c:
@@ -190,18 +190,19 @@
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (oldval != NULL) {
- lua_assert(ttistable(t) && ttisnil(oldval));
+ Table *h = hvalue(t); /* save 't' table */
+ lua_assert(ttisnil(oldval));
/* must check the metamethod */
- if ((tm = fasttm(L, hvalue(t)->metatable, TM_NEWINDEX)) == NULL &&
+ if ((tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL &&
/* no metamethod; is there a previous entry in the table? */
(oldval != luaO_nilobject ||
/* no previous entry; must create one. (The next test is
always true; we only need the assignment.) */
- (oldval = luaH_newkey(L, hvalue(t), key), 1))) {
+ (oldval = luaH_newkey(L, h, key), 1))) {
/* no metamethod and (now) there is an entry with given key */
setobj2t(L, cast(TValue *, oldval), val);
- invalidateTMcache(hvalue(t));
- luaC_barrierback(L, hvalue(t), val);
+ invalidateTMcache(h);
+ luaC_barrierback(L, h, val);
return;
}
/* else will try the metamethod */
例
do local k = 0 local x ::foo:: local y -- should be reset to nil after goto, but it is not assert(not y) y = true k = k + 1 if k < 2 then goto foo end end
パッチ
lparser.c:
@@ -1226,7 +1226,7 @@
checkrepeated(fs, ll, label); /* check for repeated labels */
checknext(ls, TK_DBCOLON); /* skip double colon */
/* create new entry for this label */
- l = newlabelentry(ls, ll, label, line, fs->pc);
+ l = newlabelentry(ls, ll, label, line, luaK_getlabel(fs));
skipnoopstat(ls); /* skip other no-op statements */
if (block_follow(ls, 0)) { /* label is last no-op statement in the block? */
/* assume that locals are already out of scope */
gmatch イテレータは、それを作成したコルーチンとは異なるコルーチンから呼び出された場合に失敗します。例
local f = string.gmatch("1 2 3 4 5", "%d+")
print(f()) --> 1
co = coroutine.wrap(f)
print(co()) --> ??? (should be 2)
パッチ
lstrlib.c:
@@ -688,6 +688,7 @@
static int gmatch_aux (lua_State *L) {
GMatchState *gm = (GMatchState *)lua_touserdata(L, lua_upvalueindex(3));
const char *src;
+ gm->ms.L = L;
for (src = gm->src; src <= gm->ms.src_end; src++) {
const char *e;
reprepstate(&gm->ms);
io.lines はオプションの最大数をチェックしません。例
-- can crash in some machines
t ={}; for i = 1, 253 do t[i] = 1 end
io.lines("someexistingfile", table.unpack(t))()
パッチ
liolib.c:
@@ -318,8 +318,15 @@
static int io_readline (lua_State *L);
+/*
+** maximum number of arguments to 'f:lines'/'io.lines' (it + 3 must fit
+** in the limit for upvalues of a closure)
+*/
+#define MAXARGLINE 250
+
static void aux_lines (lua_State *L, int toclose) {
int n = lua_gettop(L) - 1; /* number of arguments to read */
+ luaL_argcheck(L, n <= MAXARGLINE, MAXARGLINE + 2, "too many arguments");
lua_pushinteger(L, n); /* number of arguments to read */
lua_pushboolean(L, toclose); /* close/not close file when finished */
lua_rotate(L, 2, 2); /* move 'n' and 'toclose' to their positions */
string.format("%f") はバッファオーバーフローを引き起こす可能性があります (「lua_Number」がlong doubleの場合のみ)。例
string.format("%.99f", 1e4000) -- when floats are long double
パッチ
lstrlib.c:
@@ -800,3 +800,4 @@
/* maximum size of each formatted item (> len(format('%99.99f', -1e308))) */
-#define MAX_ITEM 512
+#define MAX_ITEM \
+ (sizeof(lua_Number) <= 4 ? 150 : sizeof(lua_Number) <= 8 ? 450 : 5050)
debug.getlocal を使用すると、インタプリタがクラッシュする可能性があります。例: http://lua-users.org/lists/lua-l/2015-02/msg00146.html を参照してください。
パッチ
ldebug.c:
@@ -49,4 +49,14 @@
+static void swapextra (lua_State *L) {
+ if (L->status == LUA_YIELD) {
+ CallInfo *ci = L->ci; /* get function that yielded */
+ StkId temp = ci->func; /* exchange its 'func' and 'extra' values */
+ ci->func = restorestack(L, ci->extra);
+ ci->extra = savestack(L, temp);
+ }
+}
+
+
/*
** this function can be called asynchronous (e.g. during a signal)
@@ -145,4 +155,5 @@
const char *name;
lua_lock(L);
+ swapextra(L);
if (ar == NULL) { /* information about non-active function? */
if (!isLfunction(L->top - 1)) /* not a Lua function? */
@@ -159,4 +170,5 @@
}
}
+ swapextra(L);
lua_unlock(L);
return name;
@@ -166,10 +178,13 @@
LUA_API const char *lua_setlocal (lua_State *L, const lua_Debug *ar, int n) {
StkId pos = 0; /* to avoid warnings */
- const char *name = findlocal(L, ar->i_ci, n, &pos);
+ const char *name;
lua_lock(L);
+ swapextra(L);
+ name = findlocal(L, ar->i_ci, n, &pos);
if (name) {
setobjs2s(L, pos, L->top - 1);
L->top--; /* pop value */
}
+ swapextra(L);
lua_unlock(L);
return name;
@@ -271,4 +286,5 @@
StkId func;
lua_lock(L);
+ swapextra(L);
if (*what == '>') {
ci = NULL;
@@ -289,4 +305,5 @@
api_incr_top(L);
}
+ swapextra(L);
if (strchr(what, 'L'))
collectvalidlines(L, cl);
例
mt = {__le = function (a,b) coroutine.yield("yield"); return a.x <= b.x end}
t1 = setmetatable({x=1}, mt)
t2 = {x=2}
co = coroutine.wrap(function (a,b) return t2 <= t1 end)
co()
print(co()) --> true (should be false)
パッチ
lstate.h:
@@ -94,6 +94,7 @@
#define CIST_YPCALL (1<<4) /* call is a yieldable protected call */
#define CIST_TAIL (1<<5) /* call was tail called */
#define CIST_HOOKYIELD (1<<6) /* last hook called yielded */
+#define CIST_LEQ (1<<7) /* using __lt for __le */
#define isLua(ci) ((ci)->callstatus & CIST_LUA)
lvm.c:
@@ -292,9 +292,14 @@
return l_strcmp(tsvalue(l), tsvalue(r)) <= 0;
else if ((res = luaT_callorderTM(L, l, r, TM_LE)) >= 0) /* first try 'le' */
return res;
- else if ((res = luaT_callorderTM(L, r, l, TM_LT)) < 0) /* else try 'lt' */
- luaG_ordererror(L, l, r);
- return !res;
+ else { /* try 'lt': */
+ L->ci->callstatus |= CIST_LEQ; /* mark it is doing 'lt' for 'le' */
+ res = luaT_callorderTM(L, r, l, TM_LT);
+ L->ci->callstatus ^= CIST_LEQ; /* clear mark */
+ if (res < 0)
+ luaG_ordererror(L, l, r);
+ return !res; /* result is negated */
+ }
}
@@ -553,11 +558,11 @@
case OP_LE: case OP_LT: case OP_EQ: {
int res = !l_isfalse(L->top - 1);
L->top--;
- /* metamethod should not be called when operand is K */
- lua_assert(!ISK(GETARG_B(inst)));
- if (op == OP_LE && /* "<=" using "<" instead? */
- ttisnil(luaT_gettmbyobj(L, base + GETARG_B(inst), TM_LE)))
- res = !res; /* invert result */
+ if (ci->callstatus & CIST_LEQ) { /* "<=" using "<" instead? */
+ lua_assert(op == OP_LE);
+ ci->callstatus ^= CIST_LEQ; /* clear mark */
+ res = !res; /* negate result */
+ }
lua_assert(GET_OPCODE(*ci->u.l.savedpc) == OP_JMP);
if (res != GETARG_A(inst)) /* condition failed? */
ci->u.l.savedpc++; /* skip jump instruction */
例: http://lua-users.org/lists/lua-l/2015-05/msg00376.html を参照してください。
これはLua 5.2の最後のリリースでした。後で報告されたバグは、おそらくLua 5.3で修正されています。
table.unpack でのオーバーフローチェックを最適化によって削除する可能性があります。例
unpack({}, 0, 2^31 - 1) -- crashes on some platforms with some compiler options
パッチ
ltablib.c:
@@ -134,13 +135,14 @@
static int unpack (lua_State *L) {
- int i, e, n;
+ int i, e;
+ unsigned int n;
luaL_checktype(L, 1, LUA_TTABLE);
i = luaL_optint(L, 2, 1);
e = luaL_opt(L, luaL_checkint, 3, luaL_len(L, 1));
if (i > e) return 0; /* empty range */
- n = e - i + 1; /* number of elements */
- if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */
+ n = (unsigned int)e - (unsigned int)i; /* number of elements minus 1 */
+ if (n > (INT_MAX - 10) || !lua_checkstack(L, ++n))
return luaL_error(L, "too many results to unpack");
lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */
while (i++ < e) /* push arg[i + 1...e] */
例: このバグは、インクリメンタルコレクタとプログラム間の特定のイベントのインターリーブに依存するため、非常に再現が難しいです。
パッチ
lgc.c:
@@ -403,7 +403,7 @@
reallymarkobject(g, gcvalue(gval(n))); /* mark it now */
}
}
- if (prop)
+ if (g->gcstate != GCSatomic || prop)
linktable(h, &g->ephemeron); /* have to propagate again */
else if (hasclears) /* does table have white keys? */
linktable(h, &g->allweak); /* may have to clean white keys */
例: バグの原因は初期化されていない変数の使用であるため、確実に再現することはできません。
local s = string.rep("\n", 2^24)
print(load(function () return s end))
パッチ
llex.c:
@@ -153,5 +153,5 @@
next(ls); /* skip `\n\r' or `\r\n' */
if (++ls->linenumber >= MAX_INT)
- luaX_syntaxerror(ls, "chunk has too many lines");
+ lexerror(ls, "chunk has too many lines", 0);
}
例
function f(p1, p2, p3, p4, p5, p6, p7, p8, p9, p10,
p11, p12, p13, p14, p15, p16, p17, p18, p19, p20,
p21, p22, p23, p24, p25, p26, p27, p28, p29, p30,
p31, p32, p33, p34, p35, p36, p37, p38, p39, p40,
p41, p42, p43, p44, p45, p46, p48, p49, p50, ...)
local a1, a2, a3, a4, a5, a6, a7, a8, a9, a10, a11, a12, a13, a14
end
f() -- crashes on some machines
パッチ
ldo.c:
@@ -324,7 +324,7 @@
case LUA_TLCL: { /* Lua function: prepare its call */
StkId base;
Proto *p = clLvalue(func)->p;
- luaD_checkstack(L, p->maxstacksize);
+ luaD_checkstack(L, p->maxstacksize + p->numparams);
func = restorestack(L, funcr);
n = cast_int(L->top - func) - 1; /* number of real arguments */
for (; n < p->numparams; n++)
例
function f() f() end f() -- it takes too long before a "stack overflow" error
パッチ
lgc.c:
@@ -495,2 +495,3 @@
static lu_mem traversestack (global_State *g, lua_State *th) {
+ int n = 0;
StkId o = th->stack;
@@ -505,3 +506,9 @@
}
- return sizeof(lua_State) + sizeof(TValue) * th->stacksize;
+ else { /* count call infos to compute size */
+ CallInfo *ci;
+ for (ci = &th->base_ci; ci != th->ci; ci = ci->next)
+ n++;
+ }
+ return sizeof(lua_State) + sizeof(TValue) * th->stacksize +
+ sizeof(CallInfo) * n;
}
例
-- only with Lua compiled in debug mode
print({} .. 2)
パッチ
ldebug.c:
@@ -519,5 +519,5 @@
l_noret luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
- lua_assert(!ttisstring(p1) && !ttisnumber(p2));
+ lua_assert(!ttisstring(p1) && !ttisnumber(p1));
luaG_typeerror(L, p1, "concatenate");
}
例
a,b,c = true,true,true
(a and b or c)('', '')
--> stdin:1: attempt to call a boolean value (global 'c')
-- it should be global 'b' instead of 'c'
パッチ
ldebug.c:
@@ -327,12 +327,20 @@
}
+static int filterpc (int pc, int jmptarget) {
+ if (pc < jmptarget) /* is code conditional (inside a jump)? */
+ return -1; /* cannot know who sets that register */
+ else return pc; /* current position sets that register */
+}
+
+
/*
** try to find last instruction before 'lastpc' that modified register 'reg'
*/
static int findsetreg (Proto *p, int lastpc, int reg) {
int pc;
int setreg = -1; /* keep last instruction that changed 'reg' */
+ int jmptarget = 0; /* any code before this address is conditional */
for (pc = 0; pc < lastpc; pc++) {
Instruction i = p->code[pc];
OpCode op = GET_OPCODE(i);
@@ -341,33 +349,38 @@
case OP_LOADNIL: {
int b = GETARG_B(i);
if (a <= reg && reg <= a + b) /* set registers from 'a' to 'a+b' */
- setreg = pc;
+ setreg = filterpc(pc, jmptarget);
break;
}
case OP_TFORCALL: {
- if (reg >= a + 2) setreg = pc; /* affect all regs above its base */
+ if (reg >= a + 2) /* affect all regs above its base */
+ setreg = filterpc(pc, jmptarget);
break;
}
case OP_CALL:
case OP_TAILCALL: {
- if (reg >= a) setreg = pc; /* affect all registers above base */
+ if (reg >= a) /* affect all registers above base */
+ setreg = filterpc(pc, jmptarget);
break;
}
case OP_JMP: {
int b = GETARG_sBx(i);
int dest = pc + 1 + b;
/* jump is forward and do not skip `lastpc'? */
- if (pc < dest && dest <= lastpc)
- pc += b; /* do the jump */
+ if (pc < dest && dest <= lastpc) {
+ if (dest > jmptarget)
+ jmptarget = dest; /* update 'jmptarget' */
+ }
break;
}
case OP_TEST: {
- if (reg == a) setreg = pc; /* jumped code can change 'a' */
+ if (reg == a) /* jumped code can change 'a' */
+ setreg = filterpc(pc, jmptarget);
break;
}
default:
if (testAMode(op) && reg == a) /* any instruction that set A */
- setreg = pc;
+ setreg = filterpc(pc, jmptarget);
break;
}
}
例
-- When you call 'luac -l' over this chunk, it chokes the output s="Lorem ipsum dolor sit amet, consectetur, "
パッチ
luac.c:
@@ -251,7 +251,7 @@
static void PrintConstant(const Proto* f, int i)
{
const TValue* o=&f->k[i];
- switch (ttype(o))
+ switch (ttypenv(o))
{
case LUA_TNIL:
printf("nil");
例: このバグは、長い (40文字を超える) 識別子を持つソースコードを解析するときに、GCが非常に特定の方法で実行されることに依存するため、発生 (および再現) することが非常に困難です。
パッチ
ltable.h:
@@ -18,4 +18,8 @@
#define invalidateTMcache(t) ((t)->flags = 0)
+/* returns the key, given the value of a table entry */
+#define keyfromval(v) \
+ (gkey(cast(Node *, cast(char *, (v)) - offsetof(Node, i_val))))
+
LUAI_FUNC const TValue *luaH_getint (Table *t, int key);
llex.c:
@@ -134,4 +134,7 @@
luaC_checkGC(L);
}
+ else { /* string already present */
+ ts = rawtsvalue(keyfromval(o)); /* re-use value previously stored */
+ }
L->top--; /* remove string from stack */
return ts;
luai_userstateclose の呼び出しは、__gc メソッドの呼び出しの後でのみ行う必要があります。パッチ
lstate.c: @@ -194,2 +194,4 @@ g->gcrunning = 1; /* allow gc */ + g->version = lua_version(NULL); + luai_userstateopen(L); } @@ -224,2 +226,4 @@ luaC_freeallobjects(L); /* collect all objects */ + if (g->version) /* closing a fully built state? */ + luai_userstateclose(L); luaM_freearray(L, G(L)->strt.hash, G(L)->strt.size); @@ -289,3 +293,3 @@ g->panic = NULL; - g->version = lua_version(NULL); + g->version = NULL; g->gcstate = GCSpause; @@ -308,4 +312,2 @@ } - else - luai_userstateopen(L); return L; @@ -317,3 +319,2 @@ lua_lock(L); - luai_userstateclose(L); close_state(L);
例
-- should print 'true' print(coroutine.resume(coroutine.create(function() coroutine.resume(coroutine.running()) coroutine.yield() end)))
パッチ
ldo.c: @@ -536,2 +536,3 @@ int status; + int oldnny = L->nny; /* save 'nny' */ lua_lock(L); @@ -557,3 +558,3 @@ } - L->nny = 1; /* do not allow yields */ + L->nny = oldnny; /* restore 'nny' */ L->nCcalls--;
例
print(string.find(string.rep("a", 2^20), string.rep(".?", 2^20)))
pcallが以前のエラー関数を復元しない可能性があります。例
function errfunc(x)
return 'errfunc'
end
function test(do_yield)
print(do_yield and "yielding" or "not yielding")
pcall(function() -- this pcall sets errfunc back to none
if do_yield then
coroutine.yield() -- stops errfunc from being restored
end
end)
error('fail!')
end
coro = coroutine.wrap(function()
print(xpcall(test, errfunc, false))
print(xpcall(test, errfunc, true))
print(xpcall(test, errfunc, false))
end)
coro()
--> not yielding
--> false errfunc
--> yielding
coro()
--> false temp:12: fail! <<<< should be 'errfunc' too
--> not yielding
--> false errfunc
パッチ
ldo.c:
@@ -403,7 +403,11 @@
int n;
lua_assert(ci->u.c.k != NULL); /* must have a continuation */
lua_assert(L->nny == 0);
- /* finish 'lua_callk' */
+ if (ci->callstatus & CIST_YPCALL) { /* was inside a pcall? */
+ ci->callstatus &= ~CIST_YPCALL; /* finish 'lua_pcall' */
+ L->errfunc = ci->u.c.old_errfunc;
+ }
+ /* finish 'lua_callk'/'lua_pcall' */
adjustresults(L, ci->nresults);
/* call continuation function */
if (!(ci->callstatus & CIST_STAT)) /* no call status? */
例: http://lua-users.org/lists/lua-l/2012-08/msg00149.htmlを参照してください。
パッチ
ldo.c:
@@ -311,6 +311,7 @@
ci->top = L->top + LUA_MINSTACK;
lua_assert(ci->top <= L->stack_last);
ci->callstatus = 0;
+ luaC_checkGC(L); /* stack grow uses memory */
if (L->hookmask & LUA_MASKCALL)
luaD_hook(L, LUA_HOOKCALL, -1);
lua_unlock(L);
@@ -338,6 +339,7 @@
ci->u.l.savedpc = p->code; /* starting point */
ci->callstatus = CIST_LUA;
L->top = ci->top;
+ luaC_checkGC(L); /* stack grow uses memory */
if (L->hookmask & LUA_MASKCALL)
callhook(L, ci);
return 0;
@@ -393,7 +395,6 @@
luaV_execute(L); /* call it */
if (!allowyield) L->nny--;
L->nCcalls--;
- luaC_checkGC(L);
}
loadとloadfileが間違った結果を返します。例
f = load(string.dump(function () return 1 end), nil, "b", {})
print(type(f)) --> table (should be function)
パッチ
lbaselib.c:
@@ -244,5 +244,11 @@
-static int load_aux (lua_State *L, int status) {
- if (status == LUA_OK)
+static int load_aux (lua_State *L, int status, int envidx) {
+ if (status == LUA_OK) {
+ if (envidx != 0) { /* 'env' parameter? */
+ lua_pushvalue(L, envidx); /* environment for loaded function */
+ if (!lua_setupvalue(L, -2, 1)) /* set it as 1st upvalue */
+ lua_pop(L, 1); /* remove 'env' if not used by previous call */
+ }
return 1;
+ }
else {
@@ -258,9 +264,5 @@
const char *mode = luaL_optstring(L, 2, NULL);
- int env = !lua_isnone(L, 3); /* 'env' parameter? */
+ int env = (!lua_isnone(L, 3) ? 3 : 0); /* 'env' index or 0 if no 'env' */
int status = luaL_loadfilex(L, fname, mode);
- if (status == LUA_OK && env) { /* 'env' parameter? */
- lua_pushvalue(L, 3);
- lua_setupvalue(L, -2, 1); /* set it as 1st upvalue of loaded chunk */
- }
- return load_aux(L, status);
+ return load_aux(L, status, env);
}
@@ -309,5 +311,5 @@
size_t l;
- int top = lua_gettop(L);
const char *s = lua_tolstring(L, 1, &l);
const char *mode = luaL_optstring(L, 3, "bt");
+ int env = (!lua_isnone(L, 4) ? 4 : 0); /* 'env' index or 0 if no 'env' */
if (s != NULL) { /* loading a string? */
@@ -322,7 +324,3 @@
}
- if (status == LUA_OK && top >= 4) { /* is there an 'env' argument */
- lua_pushvalue(L, 4); /* environment for loaded function */
- lua_setupvalue(L, -2, 1); /* set it as 1st upvalue */
- }
- return load_aux(L, status);
+ return load_aux(L, status, env);
}
例
collectgarbage(); print(collectgarbage'count' * 1024)
for i = 1, 100 do
local co = coroutine.create(function () end)
local x = {}
for j=1,1000 do x[j] = j end
debug.sethook(co, function () return x end, 'l')
end
collectgarbage(); print(collectgarbage'count' * 1024)
-- value should back to near the original level
パッチ
ldblib.c:
@@ -253,14 +253,15 @@
}
-#define gethooktable(L) luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY);
+#define gethooktable(L) luaL_getsubtable(L, LUA_REGISTRYINDEX, HOOKKEY)
static void hookf (lua_State *L, lua_Debug *ar) {
static const char *const hooknames[] =
{"call", "return", "line", "count", "tail call"};
gethooktable(L);
- lua_rawgetp(L, -1, L);
+ lua_pushthread(L);
+ lua_rawget(L, -2);
if (lua_isfunction(L, -1)) {
lua_pushstring(L, hooknames[(int)ar->event]);
if (ar->currentline >= 0)
@@ -306,10 +307,15 @@
count = luaL_optint(L, arg+3, 0);
func = hookf; mask = makemask(smask, count);
}
- gethooktable(L);
+ if (gethooktable(L) == 0) { /* creating hook table? */
+ lua_pushstring(L, "k");
+ lua_setfield(L, -2, "__mode"); /** hooktable.__mode = "k" */
+ lua_pushvalue(L, -1);
+ lua_setmetatable(L, -2); /* setmetatable(hooktable) = hooktable */
+ }
+ lua_pushthread(L1); lua_xmove(L1, L, 1);
lua_pushvalue(L, arg+1);
- lua_rawsetp(L, -2, L1); /* set new hook */
- lua_pop(L, 1); /* remove hook table */
+ lua_rawset(L, -3); /* set new hook */
lua_sethook(L1, func, mask, count); /* set hooks */
return 0;
}
@@ -325,7 +331,8 @@
lua_pushliteral(L, "external hook");
else {
gethooktable(L);
- lua_rawgetp(L, -1, L1); /* get hook */
+ lua_pushthread(L1); lua_xmove(L1, L, 1);
+ lua_rawget(L, -2); /* get hook */
lua_remove(L, -2); /* remove hook table */
}
lua_pushstring(L, unmakemask(mask, buff));
例
print(0xE+1)
パッチ
llex.c:
@@ -223,12 +223,19 @@
/* LUA_NUMBER */
static void read_numeral (LexState *ls, SemInfo *seminfo) {
+ const char *expo = "Ee";
+ int first = ls->current;
lua_assert(lisdigit(ls->current));
- do {
- save_and_next(ls);
- if (check_next(ls, "EePp")) /* exponent part? */
+ save_and_next(ls);
+ if (first == '0' && check_next(ls, "Xx")) /* hexadecimal? */
+ expo = "Pp";
+ for (;;) {
+ if (check_next(ls, expo)) /* exponent part? */
check_next(ls, "+-"); /* optional exponent sign */
- } while (lislalnum(ls->current) || ls->current == '.');
+ if (lisxdigit(ls->current) || ls->current == '.')
+ save_and_next(ls);
+ else break;
+ }
save(ls, '\0');
buffreplace(ls, '.', ls->decpoint); /* follow locale for decimal point */
if (!buff2d(ls->buff, &seminfo->r)) /* format error? */
例
local u = setmetatable({}, {__gc = function () foo() end})
local m = require 'mod' -- 'mod' may be any dynamic library written in C
foo = m.foo -- 'foo' may be any function from 'mod'
-- end program; it crashes
パッチ
loadlib.c:
95c95
< #define LIBPREFIX "LOADLIB: "
---
> #define CLIBS "_CLIBS"
251,266c251,256
<
< static void **ll_register (lua_State *L, const char *path) {
< void **plib;
< lua_pushfstring(L, "%s%s", LIBPREFIX, path);
< lua_gettable(L, LUA_REGISTRYINDEX); /* check library in registry? */
< if (!lua_isnil(L, -1)) /* is there an entry? */
< plib = (void **)lua_touserdata(L, -1);
< else { /* no entry yet; create one */
< lua_pop(L, 1); /* remove result from gettable */
< plib = (void **)lua_newuserdata(L, sizeof(const void *));
< *plib = NULL;
< luaL_setmetatable(L, "_LOADLIB");
< lua_pushfstring(L, "%s%s", LIBPREFIX, path);
< lua_pushvalue(L, -2);
< lua_settable(L, LUA_REGISTRYINDEX);
< }
---
> static void *ll_checkclib (lua_State *L, const char *path) {
> void *plib;
> lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
> lua_getfield(L, -1, path);
> plib = lua_touserdata(L, -1); /* plib = CLIBS[path] */
> lua_pop(L, 2); /* pop CLIBS table and 'plib' */
270a261,270
> static void ll_addtoclib (lua_State *L, const char *path, void *plib) {
> lua_getfield(L, LUA_REGISTRYINDEX, CLIBS);
> lua_pushlightuserdata(L, plib);
> lua_pushvalue(L, -1);
> lua_setfield(L, -3, path); /* CLIBS[path] = plib */
> lua_rawseti(L, -2, luaL_len(L, -2) + 1); /* CLIBS[#CLIBS + 1] = plib */
> lua_pop(L, 1); /* pop CLIBS table */
> }
>
>
272,273c272,273
< ** __gc tag method: calls library's `ll_unloadlib' function with the lib
< ** handle
---
> ** __gc tag method for CLIBS table: calls 'll_unloadlib' for all lib
> ** handles in list CLIBS
276,278c276,281
< void **lib = (void **)luaL_checkudata(L, 1, "_LOADLIB");
< if (*lib) ll_unloadlib(*lib);
< *lib = NULL; /* mark library as closed */
---
> int n = luaL_len(L, 1);
> for (; n >= 1; n--) { /* for each handle, in reverse order */
> lua_rawgeti(L, 1, n); /* get handle CLIBS[n] */
> ll_unloadlib(lua_touserdata(L, -1));
> lua_pop(L, 1); /* pop handle */
> }
284,286c287,292
< void **reg = ll_register(L, path);
< if (*reg == NULL) *reg = ll_load(L, path, *sym == '*');
< if (*reg == NULL) return ERRLIB; /* unable to load library */
---
> void *reg = ll_checkclib(L, path); /* check loaded C libraries */
> if (reg == NULL) { /* must load library? */
> reg = ll_load(L, path, *sym == '*');
> if (reg == NULL) return ERRLIB; /* unable to load library */
> ll_addtoclib(L, path, reg);
> }
292c298
< lua_CFunction f = ll_sym(L, *reg, sym);
---
> lua_CFunction f = ll_sym(L, reg, sym);
675,676c681,683
< /* create new type _LOADLIB */
< luaL_newmetatable(L, "_LOADLIB");
---
> /* create table CLIBS to keep track of loaded C libraries */
> luaL_getsubtable(L, LUA_REGISTRYINDEX, CLIBS);
> lua_createtable(L, 0, 1); /* metatable for CLIBS */
678a686
> lua_setmetatable(L, -2);
nCcallsの誤った処理。例
coroutine.wrap(function() print(pcall(pcall,pcall,pcall,pcall,pcall,error,3)) end)()
パッチ
ldo.c:
@@ -402,8 +402,6 @@
int n;
lua_assert(ci->u.c.k != NULL); /* must have a continuation */
lua_assert(L->nny == 0);
- /* finish 'luaD_call' */
- L->nCcalls--;
/* finish 'lua_callk' */
adjustresults(L, ci->nresults);
/* call continuation function */
@@ -513,7 +511,6 @@
api_checknelems(L, n);
firstArg = L->top - n; /* yield results come from continuation */
}
- L->nCcalls--; /* finish 'luaD_call' */
luaD_poscall(L, firstArg); /* finish 'luaD_precall' */
}
unroll(L, NULL);
例
local firsttime = true
local function foo ()
if firsttime then
firsttime = false
return "a = 1"
else
for i = 1, 10 do
print(debug.getlocal(2, i))
end
end
end
print(load(foo)) -- prints some lines and then crashes
例：Cで、単にyieldする行フックを設定し、任意のLua関数を呼び出します。yieldの無限ループが発生します。
これがLua 5.1の最後のリリースでした。後で報告されたバグは、ほぼ確実にLua 5.2で修正されています。
src/Makefileのコメントが移植可能ではありません。例：この不具合は、一部のmingwシステムでLuaをコンパイルする際に発生します。他のシステムには影響しないようです。
パッチ
src/Makefile: @@ -50,3 +50,3 @@ $(LUA_A): $(CORE_O) $(LIB_O) - $(AR) $@ $(CORE_O) $(LIB_O) # DLL needs all object files + $(AR) $@ $(CORE_O) $(LIB_O) $(RANLIB) $@
例
load(function () print("called"); return nil end)
--> called
--> called (should be called only once!)
パッチ
lzio.h:
@@ -59,6 +59,7 @@
lua_Reader reader;
void* data; /* additional data */
lua_State *L; /* Lua state (for reader) */
+ int eoz; /* true if reader has no more data */
};
lzio.c:
@@ -22,10 +22,14 @@
size_t size;
lua_State *L = z->L;
const char *buff;
+ if (z->eoz) return EOZ;
lua_unlock(L);
buff = z->reader(L, z->data, &size);
lua_lock(L);
- if (buff == NULL || size == 0) return EOZ;
+ if (buff == NULL || size == 0) {
+ z->eoz = 1; /* avoid calling reader function next time */
+ return EOZ;
+ }
z->n = size - 1;
z->p = buff;
return char2int(*(z->p++));
@@ -51,6 +55,7 @@
z->data = data;
z->n = 0;
z->p = NULL;
+ z->eoz = 0;
}
解決策：信頼できないソースからのプリコンパイル済みコードの実行を避けるため、ストリームの最初のバイトがエスケープ文字（10進数の27）である場合はエラーを発生させます。
例
function lunpack(i, ...)
if i == 0 then
return ...
else
return lunpack(i-1, 1, ...)
end
end
現在、Cが大きなnでlunpack(n)を呼び出すと、スタックに過剰な値が残り、スタックインデックスが混乱する可能性があります。例
print(((1 or false) and true) or false) --> 1, but should be 'true'
パッチ:(部分的な解決策; 9も参照してください)
lcode.c:
@@ -544,15 +544,18 @@
pc = NO_JUMP; /* always true; do nothing */
break;
}
- case VFALSE: {
- pc = luaK_jump(fs); /* always jump */
- break;
- }
case VJMP: {
invertjump(fs, e);
pc = e->u.s.info;
break;
}
+ case VFALSE: {
+ if (!hasjumps(e)) {
+ pc = luaK_jump(fs); /* always jump */
+ break;
+ }
+ /* else go through */
+ }
default: {
pc = jumponcond(fs, e, 0);
break;
@@ -572,14 +575,17 @@
pc = NO_JUMP; /* always false; do nothing */
break;
}
- case VTRUE: {
- pc = luaK_jump(fs); /* always jump */
- break;
- }
case VJMP: {
pc = e->u.s.info;
break;
}
+ case VTRUE: {
+ if (!hasjumps(e)) {
+ pc = luaK_jump(fs); /* always jump */
+ break;
+ }
+ /* else go through */
+ }
default: {
pc = jumponcond(fs, e, 1);
break;
luaV_settableがテーブルへの参照を無効にし、それを再利用しようとする可能性があります。例
grandparent = {}
grandparent.__newindex = function(s,_,_) print(s) end
parent = {}
parent.__newindex = parent
setmetatable(parent, grandparent)
child = setmetatable({}, parent)
child.foo = 10 --> (crash on some machines)
パッチ
lvm.c:
@@ -133,6 +133,7 @@
void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) {
int loop;
+ TValue temp;
for (loop = 0; loop < MAXTAGLOOP; loop++) {
const TValue *tm;
if (ttistable(t)) { /* `t' is a table? */
@@ -152,7 +153,9 @@
callTM(L, tm, t, key, val);
return;
}
- t = tm; /* else repeat with `tm' */
+ /* else repeat with `tm' */
+ setobj(L, &temp, tm); /* avoid pointing inside table (may rehash) */
+ t = &temp;
}
luaG_runerror(L, "loop in settable");
}
debug.getfenvは引数があるかどうかをチェックしません。例
debug.getfenv() -- should raise an error
パッチ
ldblib.c:
@@ -45,6 +45,7 @@
static int db_getfenv (lua_State *L) {
+ luaL_checkany(L, 1);
lua_getfenv(L, 1);
return 1;
}
例: http://lua-users.org/lists/lua-l/2009-11/msg00463.htmlを参照してください。
パッチ
llex.c:
@@ -118,8 +118,10 @@
lua_State *L = ls->L;
TString *ts = luaS_newlstr(L, str, l);
TValue *o = luaH_setstr(L, ls->fs->h, ts); /* entry for `str' */
- if (ttisnil(o))
+ if (ttisnil(o)) {
setbvalue(o, 1); /* make sure `str' will not be collected */
+ luaC_checkGC(L);
+ }
return ts;
}
string.formatは、引数が不足しており、書式文字列が長すぎる場合、バッファを引数として取得する可能性があります。例
x = string.rep("x", 10000) .. "%d"
print(string.format(x)) -- gives wrong error message
パッチ
lstrlib.c:
@@ -754,6 +754,7 @@
static int str_format (lua_State *L) {
+ int top = lua_gettop(L);
int arg = 1;
size_t sfl;
const char *strfrmt = luaL_checklstring(L, arg, &sfl);
@@ -768,7 +769,8 @@
else { /* format item */
char form[MAX_FORMAT]; /* to store the format (`%...') */
char buff[MAX_ITEM]; /* to store the formatted item */
- arg++;
+ if (++arg > top)
+ luaL_argerror(L, arg, "no value");
strfrmt = scanformat(L, strfrmt, form);
switch (*strfrmt++) {
case 'c': {
io.read("*n","*n")は、2回目の読み込みに失敗した場合、ガベージを返す可能性があります。例
print(io.read("*n", "*n")) --<< enter "10 hi"
--> file (0x884420) nil
パッチ
liolib.c:
@@ -276,7 +276,10 @@
lua_pushnumber(L, d);
return 1;
}
- else return 0; /* read fails */
+ else {
+ lua_pushnil(L); /* "result" to be removed */
+ return 0; /* read fails */
+ }
}
例
print((('hi' or true) and true) or true)
--> hi (should be true)
print(((nil and nil) or false) and true)
--> nil (should be false)
パッチ：(3のパッチの後に適用する必要があります)
lcode.c:
@@ -549,13 +549,6 @@
pc = e->u.s.info;
break;
}
- case VFALSE: {
- if (!hasjumps(e)) {
- pc = luaK_jump(fs); /* always jump */
- break;
- }
- /* else go through */
- }
default: {
pc = jumponcond(fs, e, 0);
break;
@@ -579,13 +572,6 @@
pc = e->u.s.info;
break;
}
- case VTRUE: {
- if (!hasjumps(e)) {
- pc = luaK_jump(fs); /* always jump */
- break;
- }
- /* else go through */
- }
default: {
pc = jumponcond(fs, e, 1);
break;
例
meta={}
setmetatable(meta, meta)
meta.__newindex = function(t, key, value) print("set") end
o = setmetatable({}, meta)
o.x = 10 -- should print 'set'
パッチ
lvm.c:
@@ -142,6 +142,7 @@
if (!ttisnil(oldval) || /* result is no nil? */
(tm = fasttm(L, h->metatable, TM_NEWINDEX)) == NULL) { /* or no TM? */
setobj2t(L, oldval, val);
+ h->flags = 0;
luaC_barriert(L, h, val);
return;
}
パッチ
lparser.c: @@ -374,9 +374,9 @@ lua_assert(luaG_checkcode(f)); lua_assert(fs->bl == NULL); ls->fs = fs->prev; - L->top -= 2; /* remove table and prototype from the stack */ /* last token read was anchored in defunct function; must reanchor it */ if (fs) anchor_token(ls); + L->top -= 2; /* remove table and prototype from the stack */ }
LUAI_MAXCSTACKは-LUA_REGISTRYINDEXより小さくなければなりません。例
j = 1e4
co = coroutine.create(function()
t = {}
for i = 1, j do t[i] = i end
return unpack(t)
end)
print(coroutine.resume(co))
パッチ
luaconf.h: 443c443,444 < ** functions to consume unlimited stack space. --- > ** functions to consume unlimited stack space. (must be smaller than > ** -LUA_REGISTRYINDEX) 445,446c446 < #define LUAI_MCS_AUX ((int)(INT_MAX / (4*sizeof(LUA_NUMBER)))) < #define LUAI_MAXCSTACK (LUAI_MCS_AUX > SHRT_MAX ? SHRT_MAX : LUAI_MCS_AUX) --- > #define LUAI_MAXCSTACK 8000
coroutine.resumeがスタックサイズを保証せずに要素をプッシュします。例：このバグは内部アサーションなしでは検出できません。
パッチ
lbaselib.c:
@@ -526,7 +526,7 @@
status = lua_resume(co, narg);
if (status == 0 || status == LUA_YIELD) {
int nres = lua_gettop(co);
- if (!lua_checkstack(L, nres))
+ if (!lua_checkstack(L, nres + 1))
luaL_error(L, "too many results to resume");
lua_xmove(co, L, nres); /* move yielded values */
return nres;
lua_checkstackは大きな'size'に対して算術オーバーフローを起こす可能性があります。例
print(unpack({1,2,3}, 0, 2^31-3))
パッチ
lapi.c:
@@ -93,15 +93,14 @@
LUA_API int lua_checkstack (lua_State *L, int size) {
- int res;
+ int res = 1;
lua_lock(L);
- if ((L->top - L->base + size) > LUAI_MAXCSTACK)
+ if (size > LUAI_MAXCSTACK || (L->top - L->base + size) > LUAI_MAXCSTACK)
res = 0; /* stack overflow */
- else {
+ else if (size > 0) {
luaD_checkstack(L, size);
if (L->ci->top < L->top + size)
L->ci->top = L->top + size;
- res = 1;
}
lua_unlock(L);
return res;
unpackは、算術オーバーフローによりクラッシュする可能性があります。例
print(unpack({1,2,3}, 2^31-1, 2^31-1))
パッチ
lbaselib.c:
@@ -344,10 +344,12 @@
luaL_checktype(L, 1, LUA_TTABLE);
i = luaL_optint(L, 2, 1);
e = luaL_opt(L, luaL_checkint, 3, luaL_getn(L, 1));
+ if (i > e) return 0; /* empty range */
n = e - i + 1; /* number of elements */
- if (n <= 0) return 0; /* empty range */
- luaL_checkstack(L, n, "table too big to unpack");
- for (; i<=e; i++) /* push arg[i...e] */
+ if (n <= 0 || !lua_checkstack(L, n)) /* n <= 0 means arith. overflow */
+ return luaL_error(L, "too many results to unpack");
+ lua_rawgeti(L, 1, i); /* push arg[i] (avoiding overflow problems) */
+ while (i++ < e) /* push arg[i + 1...e] */
lua_rawgeti(L, 1, i);
return n;
}
例
a = string.dump(function()return;end) a = a:gsub(string.char(30,37,122,128), string.char(34,0,0), 1) loadstring(a)()
パッチ
ldebug.c:
@@ -275,12 +275,12 @@
static int precheck (const Proto *pt) {
check(pt->maxstacksize <= MAXSTACK);
- lua_assert(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
- lua_assert(!(pt->is_vararg & VARARG_NEEDSARG) ||
+ check(pt->numparams+(pt->is_vararg & VARARG_HASARG) <= pt->maxstacksize);
+ check(!(pt->is_vararg & VARARG_NEEDSARG) ||
(pt->is_vararg & VARARG_HASARG));
check(pt->sizeupvalues <= pt->nups);
check(pt->sizelineinfo == pt->sizecode || pt->sizelineinfo == 0);
- check(GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
+ check(pt->sizecode > 0 && GET_OPCODE(pt->code[pt->sizecode-1]) == OP_RETURN);
return 1;
}
@@ -363,7 +363,11 @@
}
switch (op) {
case OP_LOADBOOL: {
- check(c == 0 || pc+2 < pt->sizecode); /* check its jump */
+ if (c == 1) { /* does it jump? */
+ check(pc+2 < pt->sizecode); /* check its jump */
+ check(GET_OPCODE(pt->code[pc+1]) != OP_SETLIST ||
+ GETARG_C(pt->code[pc+1]) != 0);
+ }
break;
}
case OP_LOADNIL: {
@@ -428,7 +432,10 @@
}
case OP_SETLIST: {
if (b > 0) checkreg(pt, a + b);
- if (c == 0) pc++;
+ if (c == 0) {
+ pc++;
+ check(pc < pt->sizecode - 1);
+ }
break;
}
case OP_CLOSURE: {
例
function crash(depth)
local init = '\27\76\117\97\81\0\1\4\4\4\8\0\7\0\0\0\61\115\116' ..
'\100\105\110\0\1\0\0\0\1\0\0\0\0\0\0\2\2\0\0\0\36' ..
'\0\0\0\30\0\128\0\0\0\0\0\1\0\0\0\0\0\0\0\1\0\0\0' ..
'\1\0\0\0\0\0\0\2'
local mid = '\1\0\0\0\30\0\128\0\0\0\0\0\0\0\0\0\1\0\0\0\1\0\0\0\0'
local fin = '\0\0\0\0\0\0\0\2\0\0\0\1\0\0\0\1\0\0\0\1\0\0\0\2\0' ..
'\0\0\97\0\1\0\0\0\1\0\0\0\0\0\0\0'
local lch = '\2\0\0\0\36\0\0\0\30\0\128\0\0\0\0\0\1\0\0\0\0\0\0' ..
'\0\1\0\0\0\1\0\0\0\0\0\0\2'
local rch = '\0\0\0\0\0\0\0\2\0\0\0\1\0\0\0\1\0\0\0\1\0\0\0\2\0' ..
'\0\0\97\0\1\0\0\0\1'
for i=1,depth do lch,rch = lch..lch,rch..rch end
loadstring(init .. lch .. mid .. rch .. fin)
end
for i=1,25 do print(i); crash(i) end
パッチ
lundump.c:
@@ -161,7 +160,9 @@
static Proto* LoadFunction(LoadState* S, TString* p)
{
- Proto* f=luaF_newproto(S->L);
+ Proto* f;
+ if (++S->L->nCcalls > LUAI_MAXCCALLS) error(S,"code too deep");
+ f=luaF_newproto(S->L);
setptvalue2s(S->L,S->L->top,f); incr_top(S->L);
f->source=LoadString(S); if (f->source==NULL) f->source=p;
f->linedefined=LoadInt(S);
@@ -175,6 +176,7 @@
LoadDebug(S,f);
IF (!luaG_checkcode(f), "bad code");
S->L->top--;
+ S->L->nCcalls--;
return f;
}
例
z={}
for i=1,27290 do z[i]='1,' end
z = 'if 1+1==2 then local a={' .. table.concat(z) .. '} end'
func = loadstring(z)
print(loadstring(string.dump(func)))
パッチ
ldebug.c:
@@ -346,9 +346,18 @@
int dest = pc+1+b;
check(0 <= dest && dest < pt->sizecode);
if (dest > 0) {
- /* cannot jump to a setlist count */
- Instruction d = pt->code[dest-1];
- check(!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0));
+ int j;
+ /* check that it does not jump to a setlist count; this
+ is tricky, because the count from a previous setlist may
+ have the same value of an invalid setlist; so, we must
+ go all the way back to the first of them (if any) */
+ for (j = 0; j < dest; j++) {
+ Instruction d = pt->code[dest-1-j];
+ if (!(GET_OPCODE(d) == OP_SETLIST && GETARG_C(d) == 0)) break;
+ }
+ /* if 'j' is even, previous value is not a setlist (even if
+ it looks like one) */
+ check((j&1) == 0);
}
}
break;
例
maybe = string.dump(function() return ({[true]=true})[true] end)
maybe = maybe:gsub('\1\1','\1\2')
maybe = loadstring(maybe)()
assert(type(maybe) == "boolean" and maybe ~= true and maybe ~= false)
パッチ
lundump.c:
@@ -115,7 +115,7 @@
setnilvalue(o);
break;
case LUA_TBOOLEAN:
- setbvalue(o,LoadChar(S));
+ setbvalue(o,LoadChar(S)!=0);
break;
case LUA_TNUMBER:
setnvalue(o,LoadNumber(S));
string.byteは、一部の範囲外の負のインデックスで混乱します。例
print(string.byte("abc", -5)) --> 97 98 99 (should print nothing)
パッチ
lstrlib.c:
@@ -35,7 +35,8 @@
static ptrdiff_t posrelat (ptrdiff_t pos, size_t len) {
/* relative string position: negative means back from end */
- return (pos>=0) ? pos : (ptrdiff_t)len+pos+1;
+ if (pos < 0) pos += (ptrdiff_t)len + 1;
+ return (pos >= 0) ? pos : 0;
}
例
collectgarbage("setpause", 100) -- small value
collectgarbage("setstepmul", 2000) -- large value
collectgarbage("step",0)
パッチ
lapi.c:
@@ -929,10 +929,13 @@
g->GCthreshold = g->totalbytes - a;
else
g->GCthreshold = 0;
- while (g->GCthreshold <= g->totalbytes)
+ while (g->GCthreshold <= g->totalbytes) {
luaC_step(L);
- if (g->gcstate == GCSpause) /* end of cycle? */
- res = 1; /* signal it */
+ if (g->gcstate == GCSpause) { /* end of cycle? */
+ res = 1; /* signal it */
+ break;
+ }
+ }
break;
}
case LUA_GCSETPAUSE: {
moduleがC関数の環境を変更する可能性があります。例
pcall(module, "xuxu") assert(debug.getfenv(pcall) == xuxu)
パッチ
loadlib.c:
@@ -506,8 +506,11 @@
static void setfenv (lua_State *L) {
lua_Debug ar;
- lua_getstack(L, 1, &ar);
- lua_getinfo(L, "f", &ar);
+ if (lua_getstack(L, 1, &ar) == 0 ||
+ lua_getinfo(L, "f", &ar) == 0 || /* get calling function */
+ lua_iscfunction(L, -1))
+ luaL_error(L, "function " LUA_QL("module")
+ " not called from a Lua function");
lua_pushvalue(L, -2);
lua_setfenv(L, -2);
lua_pop(L, 1);
svalueが間違っています。例
/* in luaconf.h */
#define LUAI_USER_ALIGNMENT_T union { char b[32]; }
パッチ
lobject.h: @@ -210,3 +210,3 @@ #define getstr(ts) cast(const char *, (ts) + 1) -#define svalue(o) getstr(tsvalue(o)) +#define svalue(o) getstr(rawtsvalue(o))
-nil、-true、および-falseに対して生成されたコードが間違っています。例
print(-nil)
パッチ
lcode.c:
@@ -699,7 +699,7 @@
e2.t = e2.f = NO_JUMP; e2.k = VKNUM; e2.u.nval = 0;
switch (op) {
case OPR_MINUS: {
- if (e->k == VK)
+ if (!isnumeral(e))
luaK_exp2anyreg(fs, e); /* cannot operate on non-numeric constants */
codearith(fs, OP_UNM, e, &e2);
break;
パッチ
lvm.c:
@@ -61,11 +61,9 @@
lu_byte mask = L->hookmask;
const Instruction *oldpc = L->savedpc;
L->savedpc = pc;
- if (mask > LUA_MASKLINE) { /* instruction-hook set? */
- if (L->hookcount == 0) {
- resethookcount(L);
- luaD_callhook(L, LUA_HOOKCOUNT, -1);
- }
+ if ((mask & LUA_MASKCOUNT) && L->hookcount == 0) {
+ resethookcount(L);
+ luaD_callhook(L, LUA_HOOKCOUNT, -1);
}
if (mask & LUA_MASKLINE) {
Proto *p = ci_func(L->ci)->l.p;
例
a = function(a) coroutine.wrap(a)(a) end a(a)
パッチ：'nCcalls'カウンターは、すべてのスレッドで共有する必要があります。（つまり、'lua_State'ではなく、'global_State'構造体で宣言する必要があります。）
例
a = nil; a = (1)..a
パッチ
ldebug.c:
@@ -563,8 +563,8 @@
void luaG_concaterror (lua_State *L, StkId p1, StkId p2) {
- if (ttisstring(p1)) p1 = p2;
- lua_assert(!ttisstring(p1));
+ if (ttisstring(p1) || ttisnumber(p1)) p1 = p2;
+ lua_assert(!ttisstring(p1) && !ttisnumber(p1));
luaG_typeerror(L, p1, "concatenate");
}
パッチ
ltable.c: 87,88c87,88 < n += 1; /* normalize number (avoid -0) */ < lua_assert(sizeof(a) <= sizeof(n)); --- > if (luai_numeq(n, 0)) /* avoid problems with -0 */ > return gnode(t, 0);
例
$ ulimit -s 1024 # Reduce C stack to 1MB for quicker results
$ lua -e 'local s = "a,"; for i=1,18 do s = s..s end print(loadstring("local a;"..s.."a=nil", ""))'
パッチ
lparser.c:
@@ -938,6 +938,8 @@
primaryexp(ls, &nv.v);
if (nv.v.k == VLOCAL)
check_conflict(ls, lh, &nv.v);
+ luaY_checklimit(ls->fs, nvars, LUAI_MAXCCALLS - ls->L->nCcalls,
+ "variable names");
assignment(ls, &nv, nvars+1);
}
else { /* assignment -> `=' explist1 */
例
lua -ltemp (assuming temp.lua has an error)
パッチ
lua.c:
@@ -144,7 +144,7 @@
static int dolibrary (lua_State *L, const char *name) {
lua_getglobal(L, "require");
lua_pushstring(L, name);
- return report(L, lua_pcall(L, 1, 0, 0));
+ return report(L, docall(L, 1, 1));
}
gsubは、3番目の引数なしで、大きな対象で誤って呼び出された場合、暴走する可能性があります。例
x = string.rep('a', 10000) .. string.rep('b', 10000)
print(#string.gsub(x, 'b'))
パッチ
lstrlib.c:
@@ -631,6 +631,2 @@
}
- default: {
- luaL_argerror(L, 3, "string/function/table expected");
- return;
- }
}
@@ -650,2 +646,3 @@
const char *p = luaL_checkstring(L, 2);
+ int tr = lua_type(L, 3);
int max_s = luaL_optint(L, 4, srcl+1);
@@ -655,2 +652,5 @@
luaL_Buffer b;
+ luaL_argcheck(L, tr == LUA_TNUMBER || tr == LUA_TSTRING ||
+ tr == LUA_TFUNCTION || tr == LUA_TTABLE, 3,
+ "string/function/table expected");
luaL_buffinit(L, &b);
table.removeは、範囲外のインデックスが与えられた場合、テーブルの最後の要素を削除します。例
a = {1,2,3}
table.remove(a, 4)
print(a[3]) --> nil (should be 3)
パッチ
ltablib.c:
@@ -118,7 +118,8 @@
static int tremove (lua_State *L) {
int e = aux_getn(L, 1);
int pos = luaL_optint(L, 2, e);
- if (e == 0) return 0; /* table is `empty' */
+ if (!(1 <= pos && pos <= e)) /* position is outside bounds? */
+ return 0; /* nothing to remove */
luaL_setn(L, 1, e - 1); /* t.n = n-1 */
lua_rawgeti(L, 1, pos); /* result = t[pos] */
for ( ;pos<e; pos++) {
lua_setfenvがクラッシュする可能性があります。例
> debug.setfenv(3, {})
パッチ
lapi.c:
@@ -749,7 +749,7 @@
res = 0;
break;
}
- luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
+ if (res) luaC_objbarrier(L, gcvalue(o), hvalue(L->top - 1));
L->top--;
lua_unlock(L);
return res;
例
> error(coroutine.create(function() end))
パッチ
lua.c:
@@ -74,6 +74,8 @@
static int traceback (lua_State *L) {
+ if (!lua_isstring(L, 1)) /* 'message' not a string? */
+ return 1; /* keep it intact */
lua_getfield(L, LUA_GLOBALSINDEX, "debug");
if (!lua_istable(L, -1)) {
lua_pop(L, 1);
debug.sethook/gethookがスレッドのスタックをオーバーフローさせる可能性があります。例
a = coroutine.create(function() yield() end) coroutine.resume(a) debug.sethook(a) -- may overflow the stack of 'a'
パッチ
ldblib.c:
@@ -268,12 +268,11 @@
count = luaL_optint(L, arg+3, 0);
func = hookf; mask = makemask(smask, count);
}
- gethooktable(L1);
- lua_pushlightuserdata(L1, L1);
+ gethooktable(L);
+ lua_pushlightuserdata(L, L1);
lua_pushvalue(L, arg+1);
- lua_xmove(L, L1, 1);
- lua_rawset(L1, -3); /* set new hook */
- lua_pop(L1, 1); /* remove hook table */
+ lua_rawset(L, -3); /* set new hook */
+ lua_pop(L, 1); /* remove hook table */
lua_sethook(L1, func, mask, count); /* set hooks */
return 0;
}
@@ -288,11 +287,10 @@
if (hook != NULL && hook != hookf) /* external hook? */
lua_pushliteral(L, "external hook");
else {
- gethooktable(L1);
- lua_pushlightuserdata(L1, L1);
- lua_rawget(L1, -2); /* get hook */
- lua_remove(L1, -2); /* remove hook table */
- lua_xmove(L1, L, 1);
+ gethooktable(L);
+ lua_pushlightuserdata(L, L1);
+ lua_rawget(L, -2); /* get hook */
+ lua_remove(L, -2); /* remove hook table */
}
lua_pushstring(L, unmakemask(mask, buff));
lua_pushinteger(L, lua_gethookcount(L1));
例
a = {}
a[1] = "x={1"
for i = 2, 2^20 do
a[i] = 1
end
a[#a + 1] = "}"
s = table.concat(a, ",")
assert(loadstring(s))()
print(#x)
パッチ
lparser.c:
@@ -489,7 +489,7 @@
static void listfield (LexState *ls, struct ConsControl *cc) {
expr(ls, &cc->v);
- luaY_checklimit(ls->fs, cc->na, MAXARG_Bx, "items in a constructor");
+ luaY_checklimit(ls->fs, cc->na, MAX_INT, "items in a constructor");
cc->na++;
cc->tostore++;
}
例
local Var local function main() NoSuchName (function() Var=0 end) end main()エラーメッセージは、アップバリュー'Var'（nil値）を呼び出そうとしましたです。グローバル'NoSuchName'（nil値）を呼び出そうとしましたである必要があります。
パッチ
ldebug.c:
@@ -435,14 +435,16 @@
break;
}
case OP_CLOSURE: {
- int nup;
+ int nup, j;
check(b < pt->sizep);
nup = pt->p[b]->nups;
check(pc + nup < pt->sizecode);
- for (; nup>0; nup--) {
- OpCode op1 = GET_OPCODE(pt->code[pc+nup]);
+ for (j = 1; j <= nup; j++) {
+ OpCode op1 = GET_OPCODE(pt->code[pc + j]);
check(op1 == OP_GETUPVAL || op1 == OP_MOVE);
}
+ if (reg != NO_REG) /* tracing? */
+ pc += nup; /* do not 'execute' these pseudo-instructions */
break;
}
case OP_VARARG: {
string.format("%")が文字列を越えて読み取る可能性があります。例
print(string.format("%"))
パッチ
lstrlib.c:
@@ -723,7 +723,7 @@
static const char *scanformat (lua_State *L, const char *strfrmt, char *form) {
const char *p = strfrmt;
- while (strchr(FLAGS, *p)) p++; /* skip flags */
+ while (*p != '\0' && strchr(FLAGS, *p) != NULL) p++; /* skip flags */
if ((size_t)(p - strfrmt) >= sizeof(FLAGS))
luaL_error(L, "invalid format (repeated flags)");
if (isdigit(uchar(*p))) p++; /* skip width */
os.dateは、結果が空の文字列の場合にエラーをスローします。例
print(os.date(""))
パッチ
loslib.c:
@@ -148,7 +148,18 @@
else {
- char b[256];
- if (strftime(b, sizeof(b), s, stm))
- lua_pushstring(L, b);
- else
- return luaL_error(L, LUA_QL("date") " format too long");
+ char cc[3];
+ luaL_Buffer b;
+ cc[0] = '%'; cc[2] = '\0';
+ luaL_buffinit(L, &b);
+ for (; *s; s++) {
+ if (*s != '%' || *(s + 1) == '\0') /* no conversion specifier? */
+ luaL_addchar(&b, *s);
+ else {
+ size_t reslen;
+ char buff[200]; /* should be big enough for any conversion result */
+ cc[1] = *(++s);
+ reslen = strftime(buff, sizeof(buff), cc, stm);
+ luaL_addlstring(&b, buff, reslen);
+ }
+ }
+ luaL_pushresult(&b);
}
setfenvは無効な最初の引数を受け入れます。例
setfenv(nil, {}) -- should throw an error
パッチ
lbaselib.c:
@@ -116,3 +116,3 @@
-static void getfunc (lua_State *L) {
+static void getfunc (lua_State *L, int opt) {
if (lua_isfunction(L, 1)) lua_pushvalue(L, 1);
@@ -120,3 +120,3 @@
lua_Debug ar;
- int level = luaL_optint(L, 1, 1);
+ int level = opt ? luaL_optint(L, 1, 1) : luaL_checkint(L, 1);
luaL_argcheck(L, level >= 0, 1, "level must be non-negative");
@@ -133,3 +133,3 @@
static int luaB_getfenv (lua_State *L) {
- getfunc(L);
+ getfunc(L, 1);
if (lua_iscfunction(L, -1)) /* is a C function? */
@@ -144,3 +144,3 @@
luaL_checktype(L, 2, LUA_TTABLE);
- getfunc(L);
+ getfunc(L, 0);
lua_pushvalue(L, 2);
例
-- use a large number of names (almost 256)
v1=1; v2=1; v3=1; v4=1; v5=1; v6=1; v7=1; v8=1; v9=1;
v10=1; v11=1; v12=1; v13=1; v14=1; v15=1; v16=1; v17=1;
v18=1; v19=1; v20=1; v21=1; v22=1; v23=1; v24=1; v25=1;
v26=1; v27=1; v28=1; v29=1; v30=1; v31=1; v32=1; v33=1;
v34=1; v35=1; v36=1; v37=1; v38=1; v39=1; v40=1; v41=1;
v42=1; v43=1; v44=1; v45=1; v46=1; v47=1; v48=1; v49=1;
v50=1; v51=1; v52=1; v53=1; v54=1; v55=1; v56=1; v57=1;
v58=1; v59=1; v60=1; v61=1; v62=1; v63=1; v64=1; v65=1;
v66=1; v67=1; v68=1; v69=1; v70=1; v71=1; v72=1; v73=1;
v74=1; v75=1; v76=1; v77=1; v78=1; v79=1; v80=1; v81=1;
v82=1; v83=1; v84=1; v85=1; v86=1; v87=1; v88=1; v89=1;
v90=1; v91=1; v92=1; v93=1; v94=1; v95=1; v96=1; v97=1;
v98=1; v99=1; v100=1; v101=1; v102=1; v103=1; v104=1; v105=1;
v106=1; v107=1; v108=1; v109=1; v110=1; v111=1; v112=1; v113=1;
v114=1; v115=1; v116=1; v117=1; v118=1; v119=1; v120=1; v121=1;
v122=1; v123=1; v124=1; v125=1; v126=1; v127=1; v128=1; v129=1;
v130=1; v131=1; v132=1; v133=1; v134=1; v135=1; v136=1; v137=1;
v138=1; v139=1; v140=1; v141=1; v142=1; v143=1; v144=1; v145=1;
v146=1; v147=1; v148=1; v149=1; v150=1; v151=1; v152=1; v153=1;
v154=1; v155=1; v156=1; v157=1; v158=1; v159=1; v160=1; v161=1;
v162=1; v163=1; v164=1; v165=1; v166=1; v167=1; v168=1; v169=1;
v170=1; v171=1; v172=1; v173=1; v174=1; v175=1; v176=1; v177=1;
v178=1; v179=1; v180=1; v181=1; v182=1; v183=1; v184=1; v185=1;
v186=1; v187=1; v188=1; v189=1; v190=1; v191=1; v192=1; v193=1;
v194=1; v195=1; v196=1; v197=1; v198=1; v199=1; v200=1; v201=1;
v202=1; v203=1; v204=1; v205=1; v206=1; v207=1; v208=1; v209=1;
v210=1; v211=1; v212=1; v213=1; v214=1; v215=1; v216=1; v217=1;
v218=1; v219=1; v220=1; v221=1; v222=1; v223=1; v224=1; v225=1;
v226=1; v227=1; v228=1; v229=1; v230=1; v231=1; v232=1; v233=1;
v234=1; v235=1; v236=1; v237=1; v238=1; v239=1; v240=1; v241=1;
v242=1; v243=1; v244=1; v245=1; v246=1; v247=1; v248=1; v249=1;
v250=1;
v251={k1 = 1};
v252=1;
print(2 * v251.k1, v251.k1 * 2); -- 2 2, OK
v253=1;
print(2 * v251.k1, v251.k1 * 2); -- 1 2, ???
パッチ
lcode.c:
@@ -657,10 +657,16 @@
if (constfolding(op, e1, e2))
return;
else {
- int o1 = luaK_exp2RK(fs, e1);
int o2 = (op != OP_UNM && op != OP_LEN) ? luaK_exp2RK(fs, e2) : 0;
- freeexp(fs, e2);
- freeexp(fs, e1);
+ int o1 = luaK_exp2RK(fs, e1);
+ if (o1 > o2) {
+ freeexp(fs, e1);
+ freeexp(fs, e2);
+ }
+ else {
+ freeexp(fs, e2);
+ freeexp(fs, e1);
+ }
e1->u.s.info = luaK_codeABC(fs, op, 0, o1, o2);
e1->k = VRELOCABLE;
}
@@ -718,10 +724,15 @@
luaK_exp2nextreg(fs, v); /* operand must be on the `stack' */
break;
}
- default: {
+ case OPR_ADD: case OPR_SUB: case OPR_MUL: case OPR_DIV:
+ case OPR_MOD: case OPR_POW: {
if (!isnumeral(v)) luaK_exp2RK(fs, v);
break;
}
+ default: {
+ luaK_exp2RK(fs, v);
+ break;
+ }
}
}
例
function f (a)
a=nil
return a
end
print(f("test"))
パッチ
lcode.c:
@@ -35,16 +35,20 @@
void luaK_nil (FuncState *fs, int from, int n) {
Instruction *previous;
if (fs->pc > fs->lasttarget) { /* no jumps to current position? */
- if (fs->pc == 0) /* function start? */
- return; /* positions are already clean */
- previous = &fs->f->code[fs->pc-1];
- if (GET_OPCODE(*previous) == OP_LOADNIL) {
- int pfrom = GETARG_A(*previous);
- int pto = GETARG_B(*previous);
- if (pfrom <= from && from <= pto+1) { /* can connect both? */
- if (from+n-1 > pto)
- SETARG_B(*previous, from+n-1);
- return;
+ if (fs->pc == 0) { /* function start? */
+ if (from >= fs->nactvar)
+ return; /* positions are already clean */
+ }
+ else {
+ previous = &fs->f->code[fs->pc-1];
+ if (GET_OPCODE(*previous) == OP_LOADNIL) {
+ int pfrom = GETARG_A(*previous);
+ int pto = GETARG_B(*previous);
+ if (pfrom <= from && from <= pto+1) { /* can connect both? */
+ if (from+n-1 > pto)
+ SETARG_B(*previous, from+n-1);
+ return;
+ }
}
}
}
例
a = {}
setmetatable(a, {__concat = function (a,b) print(type(a), type(b)) end})
a = 4 .. a
パッチ
lvm.c:
@@ -281,10 +281,12 @@
do {
StkId top = L->base + last + 1;
int n = 2; /* number of elements handled in this pass (at least 2) */
- if (!tostring(L, top-2) || !tostring(L, top-1)) {
+ if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) {
if (!call_binTM(L, top-2, top-1, top-2, TM_CONCAT))
luaG_concaterror(L, top-2, top-1);
- } else if (tsvalue(top-1)->len > 0) { /* if len=0, do nothing */
+ } else if (tsvalue(top-1)->len == 0) /* second op is empty? */
+ (void)tostring(L, top - 2); /* result is first op (as string) */
+ else {
/* at least two string values; get as many as possible */
size_t tl = tsvalue(top-1)->len;
char *buffer;
loadlib.c はライブラリであり、Lua の内部（lobject.h 経由）にアクセスすべきではない。例：このバグは外部の動作に影響を与えません。
パッチ：loadlib.c で、luaO_pushfstring の出現箇所をすべて lua_pushfstring に変更してください。
例
print(false or 0) -- on 16-bit machines
パッチ
lcode.c:
@@ -731,17 +731,15 @@
case OPR_AND: {
lua_assert(e1->t == NO_JUMP); /* list must be closed */
luaK_dischargevars(fs, e2);
- luaK_concat(fs, &e1->f, e2->f);
- e1->k = e2->k; e1->u.s.info = e2->u.s.info;
- e1->u.s.aux = e2->u.s.aux; e1->t = e2->t;
+ luaK_concat(fs, &e2->f, e1->f);
+ *e1 = *e2;
break;
}
case OPR_OR: {
lua_assert(e1->f == NO_JUMP); /* list must be closed */
luaK_dischargevars(fs, e2);
- luaK_concat(fs, &e1->t, e2->t);
- e1->k = e2->k; e1->u.s.info = e2->u.s.info;
- e1->u.s.aux = e2->u.s.aux; e1->f = e2->f;
+ luaK_concat(fs, &e2->t, e1->t);
+ *e1 = *e2;
break;
}
luaL_checkudata が誤ったエラーメッセージを生成する可能性がある。例
getmetatable(io.stdin).__gc() --> bad argument #1 to '__gc' (FILE* expected, got table)
パッチ
lauxlib.c:
@@ -123,11 +123,17 @@
LUALIB_API void *luaL_checkudata (lua_State *L, int ud, const char *tname) {
void *p = lua_touserdata(L, ud);
- lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */
- if (p == NULL || !lua_getmetatable(L, ud) || !lua_rawequal(L, -1, -2))
- luaL_typerror(L, ud, tname);
- lua_pop(L, 2); /* remove both metatables */
- return p;
+ if (p != NULL) { /* value is a userdata? */
+ if (lua_getmetatable(L, ud)) { /* does it have a metatable? */
+ lua_getfield(L, LUA_REGISTRYINDEX, tname); /* get correct metatable */
+ if (lua_rawequal(L, -1, -2)) { /* does it have the correct mt? */
+ lua_pop(L, 2); /* remove both metatables */
+ return p;
+ }
+ }
+ }
+ luaL_typerror(L, ud, tname); /* else error */
+ return NULL; /* to avoid warnings */
}
パッチ：最も簡単な解決策は、D3DCREATE_FPU_PRESERVE フラグを使用して DirectX を使用することです。それ以外の場合は、luaconf.h 内の lua_number2int の定義を以下のように変更できます
#define lua_number2int(i,d) __asm fld d __asm fistp i
string.formatE の '%q' オプションが '\r' を正しく処理しない。例
local s = "a string with \r and \n and \r\n and \n\r"
local c = string.format("return %q", s)
assert(assert(loadstring(c))() == s)
パッチ
lstrlib.c:
@@ -703,6 +703,10 @@
luaL_addchar(b, *s);
break;
}
+ case '\r': {
+ luaL_addlstring(b, "\\r", 2);
+ break;
+ }
case '\0': {
luaL_addlstring(b, "\\000", 4);
break;
luaL_dofile と luaL_dostring は、チャンクによって返されるすべての値を返す必要がある。パッチ
lauxlib.h: @@ -108,9 +108,11 @@ #define luaL_typename(L,i) lua_typename(L, lua_type(L,(i))) -#define luaL_dofile(L, fn) (luaL_loadfile(L, fn) || lua_pcall(L, 0, 0, 0)) +#define luaL_dofile(L, fn) \ + (luaL_loadfile(L, fn) || lua_pcall(L, 0, LUA_MULTRET, 0)) -#define luaL_dostring(L, s) (luaL_loadstring(L, s) || lua_pcall(L, 0, 0, 0)) +#define luaL_dostring(L, s) \ + (luaL_loadstring(L, s) || lua_pcall(L, 0, LUA_MULTRET, 0)) #define luaL_getmetatable(L,n) (lua_getfield(L, LUA_REGISTRYINDEX, (n)))
パッチ
lgc.c:
@@ -322,4 +322,6 @@
-static void propagateall (global_State *g) {
- while (g->gray) propagatemark(g);
+static size_t propagateall (global_State *g) {
+ size_t m = 0;
+ while (g->gray) m += propagatemark(g);
+ return m;
}
@@ -542,3 +544,3 @@
marktmu(g); /* mark `preserved' userdata */
- propagateall(g); /* remark, to propagate `preserveness' */
+ udsize += propagateall(g); /* remark, to propagate `preserveness' */
cleartable(g->weak); /* remove collected objects from weak tables */
@@ -592,2 +594,4 @@
GCTM(L);
+ if (g->estimate > GCFINALIZECOST)
+ g->estimate -= GCFINALIZECOST;
例
co = coroutine.create(function () coroutine.yield() end) debug.sethook(co, function() end, "lr") coroutine.resume(co) coroutine.resume(co)
パッチ
ldo.c:
@@ -389,6 +389,7 @@
return;
}
else { /* resuming from previous yield */
+ L->status = 0;
if (!f_isLua(ci)) { /* `common' yield? */
/* finish interrupted execution of `OP_CALL' */
lua_assert(GET_OPCODE(*((ci-1)->savedpc - 1)) == OP_CALL ||
@@ -399,7 +400,6 @@
else /* yielded inside a hook: just continue its execution */
L->base = L->ci->base;
}
- L->status = 0;
luaV_execute(L, cast_int(L->ci - L->base_ci));
}
これは Lua 5.0 の最後のリリースです。後で報告されたバグは、ほとんどの場合 Lua 5.1 で修正されています。
例
longs = string.rep("\0", 2^25)
function catter(i)
return assert(loadstring(
string.format("return function(a) return a%s end",
string.rep("..a", i-1))))()
end
rep129 = catter(129)
rep129(longs)
パッチ
lvm.c:
@@ -321,15 +321,15 @@
luaG_concaterror(L, top-2, top-1);
} else if (tsvalue(top-1)->tsv.len > 0) { /* if len=0, do nothing */
/* at least two string values; get as many as possible */
- lu_mem tl = cast(lu_mem, tsvalue(top-1)->tsv.len) +
- cast(lu_mem, tsvalue(top-2)->tsv.len);
+ size_t tl = tsvalue(top-1)->tsv.len;
char *buffer;
int i;
- while (n < total && tostring(L, top-n-1)) { /* collect total length */
- tl += tsvalue(top-n-1)->tsv.len;
- n++;
+ /* collect total length */
+ for (n = 1; n < total && tostring(L, top-n-1); n++) {
+ size_t l = tsvalue(top-n-1)->tsv.len;
+ if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow");
+ tl += l;
}
- if (tl > MAX_SIZET) luaG_runerror(L, "string size overflow");
buffer = luaZ_openspace(L, &G(L)->buff, tl);
tl = 0;
for (i=n; i>0; i--) { /* concat all strings */
lua_getupvalue と lua_setupvalue が、小さすぎるインデックスをチェックしない。例
debug.getupvalue(function() end, 0)
パッチ
lapi.c 941c941 < if (n > f->c.nupvalues) return NULL; --- > if (!(1 <= n && n <= f->c.nupvalues)) return NULL; 947c947 < if (n > p->sizeupvalues) return NULL; --- > if (!(1 <= n && n <= p->sizeupvalues)) return NULL;
例
local thread_id = 0
local threads = {}
function fn(thread)
thread_id = thread_id + 1
threads[thread_id] = function()
thread = nil
end
coroutine.yield()
end
while true do
local thread = coroutine.create(fn)
coroutine.resume(thread, thread)
end
パッチ
lgc.c:
221,224c221,222
< if (!u->marked) {
< markobject(st, &u->value);
< u->marked = 1;
< }
---
> markobject(st, u->v);
> u->marked = 1;
rawset と rawget が余分な引数を無視しない。例
a = {}
rawset(a, 1, 2, 3)
print(a[1], a[2]) -- should be 2 and nil
パッチ
lbaselib.c: 175a176 > lua_settop(L, 2); 183a185 > lua_settop(L, 3);
例
a = {}
print(gcinfo())
for i = 1, 10000 do
a[i] = setmetatable({}, {__mode = "v"})
end
collectgarbage()
a = nil
collectgarbage()
print(gcinfo())
パッチ
lgc.c
@@ -366,7 +366,7 @@
GCObject *curr;
int count = 0; /* number of collected items */
while ((curr = *p) != NULL) {
- if (curr->gch.marked > limit) {
+ if ((curr->gch.marked & ~(KEYWEAK | VALUEWEAK)) > limit) {
unmark(curr);
p = &curr->gch.next;
}
例
-- should print false, but prints nil print(not not (nil and 4))
io.popen で作成された）"パイプ付きファイル" を閉じると Lua がクラッシュする可能性がある。例
f = io.popen("ls")
f:close()
lua_closethread はマニュアルにのみ存在する。解決策：マニュアルが間違っています。スレッドはガベージコレクションの対象です。
例
function co_func (current_co) coroutine.resume(co) end co = coroutine.create(co_func) coroutine.resume(co) coroutine.resume(co) --> crash
パッチ
ldo.c:
325,326c325
< if (nargs >= L->top - L->base)
< luaG_runerror(L, "cannot resume dead coroutine");
---
> lua_assert(nargs < L->top - L->base);
329c328,329
< else if (ci->state & CI_YIELD) { /* inside a yield? */
---
> else { /* inside a yield */
> lua_assert(ci->state & CI_YIELD);
344,345d343
< else
< luaG_runerror(L, "cannot resume non-suspended coroutine");
351a350,358
> static int resume_error (lua_State *L, const char *msg) {
> L->top = L->ci->base;
> setsvalue2s(L->top, luaS_new(L, msg));
> incr_top(L);
> lua_unlock(L);
> return LUA_ERRRUN;
> }
>
>
355a363,368
> if (L->ci == L->base_ci) {
> if (nargs >= L->top - L->base)
> return resume_error(L, "cannot resume dead coroutine");
> }
> else if (!(L->ci->state & CI_YIELD)) /* not inside a yield? */
> return resume_error(L, "cannot resume non-suspended coroutine");
file:close を呼び出すことができない（クラッシュが発生する）。例
> io.stdin.close() -- correct call should be io.stdin:close()
パッチ
liolib.c:
161c161
< if (lua_isnone(L, 1)) {
---
> if (lua_isnone(L, 1) && lua_type(L, lua_upvalueindex(1)) == LUA_TTABLE) {
例：lua.c を変更して、lua_assert が定義された状態で Lua を再コンパイルする必要があります。
lua.c: 381a382 > lua_checkstack(l, 1000);
パッチ
lgc.c: 247c247 < if (!(ci->state & CI_C) && lim < ci->top) --- > if (lim < ci->top)
例
function g(x)
coroutine.yield(x)
end
function f (i)
debug.sethook(print, "l")
for j=1,1000 do
g(i+j)
end
end
co = coroutine.wrap(f)
co(10)
pcall(co)
pcall(co)
パッチ
lvm.c: 402d401 < L->ci->u.l.pc = &pc; 405a405 > L->ci->u.l.pc = &pc; 676,678c676 < lua_assert(ci->u.l.pc == &pc && < ttisfunction(ci->base - 1) && < (ci->state & CI_SAVEDPC)); --- > lua_assert(ttisfunction(ci->base - 1) && (ci->state & CI_SAVEDPC));
例
a = newproxy(true) getmetatable(a).__gc = function () end for i=1,10000000 do newproxy(a) if math.mod(i, 10000) == 0 then print(gcinfo()) end end
パッチ
lgc.h:
18c18
< void luaC_separateudata (lua_State *L);
---
> size_t luaC_separateudata (lua_State *L);
lgc.c:
113c113,114
< void luaC_separateudata (lua_State *L) {
---
> size_t luaC_separateudata (lua_State *L) {
> size_t deadmem = 0;
127a129
> deadmem += sizeudata(gcotou(curr)->uv.len);
136a139
> return deadmem;
390c393
< static void checkSizes (lua_State *L) {
---
> static void checkSizes (lua_State *L, size_t deadmem) {
400c403
< G(L)->GCthreshold = 2*G(L)->nblocks; /* new threshold */
---
> G(L)->GCthreshold = 2*G(L)->nblocks - deadmem; /* new threshold */
454c457,458
< static void mark (lua_State *L) {
---
> static size_t mark (lua_State *L) {
> size_t deadmem;
467c471
< luaC_separateudata(L); /* separate userdata to be preserved */
---
> deadmem = luaC_separateudata(L); /* separate userdata to be preserved */
475a480
> return deadmem;
480c485
< mark(L);
---
> size_t deadmem = mark(L);
482c487
< checkSizes(L);
---
> checkSizes(L, deadmem);
tostring でバッファオーバーフローを引き起こす可能性がある。例
print{} -- on an AS400 machine
パッチ
liolib.c: 178c178 < char buff[32]; --- > char buff[128]; lbaselib.c: 327c327 < char buff[64]; --- > char buff[128];
local function がスタックサイズを増やさない。例
-- must run this with precompiled code local a,b,c local function d () end
パッチ
lparser.c: 1143a1144 > FuncState *fs = ls->fs; 1145c1146,1147 < init_exp(&v, VLOCAL, ls->fs->freereg++); --- > init_exp(&v, VLOCAL, fs->freereg); > luaK_reserveregs(fs, 1); 1148c1150,1152 < luaK_storevar(ls->fs, &v, &b); --- > luaK_storevar(fs, &v, &b); > /* debug information will only see the variable after this point! */ > getlocvar(fs, fs->nactvar - 1).startpc = fs->pc;
例
以下のようにフックを設定してください。カウントフックを設定せずに正のカウントを使用することは奇妙ですが、間違っているわけではありません。
lua_sethook(L, my_hook, LUA_MASKLINE | LUA_MASKRET, 1);
パッチ
lvm.c:
69c69
< if (mask > LUA_MASKLINE) { /* instruction-hook set? */
---
> if (mask & LUA_MASKCOUNT) { /* instruction-hook set? */
dofile が引数なしで呼び出された場合、1つの戻り値を無視する。例
a,b = dofile() --< here you enter `return 1,2,3 <eof>' print(a,b) --> 2 3 (should be 1 and 2)
パッチ
lbaselib.c: 313a314 > int n = lua_gettop(L); 317c318 < return lua_gettop(L) - 1; --- > return lua_gettop(L) - n;
lua_getupvalue と lua_setupvalue が、小さすぎるインデックスをチェックしない。rawset と rawget が余分な引数を無視しない。Lua 4.0 のほとんどのバグは、Lua 4.0.1 以降のバージョンで修正されています。
lua_pushuserdata(L,NULL) が機能しない。while 1 dostring[[print('hello\n')]] end がメモリを再利用しない。ULONG_MAX>>10 が int に収まらない可能性がある。