错误
错误
这是自 4.0 以来 Lua 的每个版本中发现的所有错误的列表。
每个条目都包含一个展示错误的最小示例以及一个补丁或解决方案（如果可用）。较大的修复出现在Lua 的 GitHub 存储库中，该存储库会不定期镜像。除非另有说明，否则每个 Lua 版本都会修复以前版本中列出的所有错误。较新版本中发现的一些错误可能存在于较旧版本中。
如果您要报告错误，请先阅读此内容。
示例
-- 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")
示例
/* 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);
}
示例
-- error should be at line 3 foo ( 0 ) --> lua: temp:2: attempt to call a nil value (global 'foo')
示例
-- 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())
示例
a = {_ENV = {}}
print(a._ENV.x + 1)
--> attempt to perform arithmetic on a nil value (global 'x')
示例
-- seg.faults in 32-bit machines local a = 'Name' for b = -1000, 0 do a = a .. '____________' .. a .. '____________' .. a .. a .. '____________' end
示例
*** 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
示例
-- Lua compiled with assertions on local _ENV <const> = 0 X=0
示例
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))
示例
print(
xpcall((0),
function(...)
local f
if d[print(print(print(print(t[...]))))] then
end
end
)
)
示例
-- (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)
示例
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()
示例
-- the following code should raise an error
for pos, cp in utf8.codes('in\xbfvalid') do
print(pos, cp)
end
示例
-- 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))
示例
local a = 0 local b = 1 print(b // a) --> lua: temp:1: attempt to divide by zero
示例
-- 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))
示例
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()
补丁
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 */
示例
-- 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
补丁
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);
示例
local x<const> = {}
function x() end -- should raise an error
print(x)
示例
-- (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)
补丁
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");
示例
-- Lua compiled in gcc with option '-fsanitize=undefined' print(1 >> math.mininteger)
补丁
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? */
示例
local function func() pcall(1) coroutine.wrap(func)() end func()
示例
-- 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()
示例
-- The following chunk may segfault
function v (...)
return os.exit(0, true)
end
local x <close> = setmetatable({}, {__close = error})
v()
示例
function func1 ()
local f = setmetatable({}, {__gc = function () collectgarbage("step") end})
collectgarbage("step" , 1)
end
for i = 0,1000 do
setmetatable({}, {__gc = func1})
end
示例
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()
示例
-- 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})
示例
nan = 0/0
t = {nan, nan, 20, 10}
table.sort(t)
print(table.concat(t, ", "))
--> -nan, 20, -nan, 10
补丁：手册具有欺骗性。排序函数定义偏序是必要的，但还不够。
示例
-- with Lua compiled with option LUA_USE_APICHECK debug.getinfo(0, ">")
补丁
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 */
示例
-- the following call gives an error message with a wrong index
table.concat({}, "", math.maxinteger, math.maxinteger)
补丁
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);
}
示例：此错误可能不会导致平面内存架构中的故障。我们可以通过使用 gcc 选项“-fsanitize=pointer-subtract”（以及使其正常工作所需的选项）编译 Lua 并运行以下代码来强制执行此错误
print(setmetatable({}, {__index = 4}).x)
示例
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
示例
-- 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
补丁
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);
示例
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))
补丁
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);
示例
-- 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
补丁
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);
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2020-07/msg00053.html。
补丁
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);
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2020-07/msg00054.html。
补丁
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' */
示例：https://lua-users.lua.ac.cn/lists/lua-l/2020-07/msg00078.html。
补丁
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 */
示例：(依赖于系统)
补丁
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;
示例
-- 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
补丁
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' */
}
}
}
示例
function errfunc () return 10 + xpcall(nil, errfunc) end coroutine.resume(coroutine.create(function() xpcall(nil, errfunc) end))
示例
-- 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")
示例
print(debug.getlocal(1, 2^31))
示例
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)
示例
-- 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')
这是 Lua 5.3 的最后一个版本。之后报告的错误很可能已在 Lua 5.4 中修复。
补丁
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"
补丁
Makefile: @@ -49 +49 @@ -R= $V.4 +R= $V.5
示例
local eqs = string.rep("=", 0x3ffffffe)
local code = "return [" .. eqs .. "[a]" .. eqs .. "]"
print(#assert(load(code))())
示例
-- the next code may crash the machine
f=load(function() end)
interesting={}
interesting[0]=string.rep("A",512)
debug.upvaluejoin(f,1,f,1)
补丁
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++;
示例
-- should print 32323232..., but prints only '3' if true then goto LBL ::loop:: print(2) ::LBL:: print(3) goto loop end
补丁
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 */
示例
-- crashes if machine has enough memory
local t = {}
for i = 1, 0x7fffffff do
t[i] = i
end
补丁
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? */
示例
-- on a machine with enough memory
local t = {}
for i = 1, 2147483681 do
t[i] = i
end
print(#t)
补丁
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;
示例
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
补丁
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);
示例
-- 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'])
补丁
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 不应调用垃圾回收器。
补丁
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);
}
示例
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
补丁
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 */
示例
-- the next loop will probably crash the interpreter repeat until load "for _ in _,_,_,_ do local function _() end"
补丁
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 的格式可能会读取格式字符串。
示例：此错误似乎不会发生在常规编译器中。它需要一个“拦截器”'memcmp' 函数，该函数在找到差异后继续读取内存。
补丁
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) {
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2016-07/msg00303.html。
补丁
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 */
示例
-- 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()
示例
local mt = {}
mt.__newindex = mt
local t = setmetatable({}, mt)
t[1] = 1 -- will segfault on some machines
补丁
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 */
示例
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
补丁
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 迭代器将失败。
示例
local f = string.gmatch("1 2 3 4 5", "%d+")
print(f()) --> 1
co = coroutine.wrap(f)
print(co()) --> ??? (should be 2)
补丁
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 不检查最大选项数。
示例
-- can crash in some machines
t ={}; for i = 1, 253 do t[i] = 1 end
io.lines("someexistingfile", table.unpack(t))()
补丁
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") 可能会导致缓冲区溢出（仅当 'lua_Number' 为 long double 时！）。
示例
string.format("%.99f", 1e4000) -- when floats are long double
补丁
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 可能会导致解释器崩溃。
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2015-02/msg00146.html。
补丁
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);
示例
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)
补丁
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 */
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2015-05/msg00376.html。
这是 Lua 5.2 的最后一个版本。稍后报告的错误很可能已在 Lua 5.3 中修复。
table.unpack 中优化溢出检查。
示例
unpack({}, 0, 2^31 - 1) -- crashes on some platforms with some compiler options
补丁
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] */
示例：此错误非常难以重现，因为它取决于增量收集器和程序之间事件的特定交错。
补丁
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 */
示例：此错误的原因是使用了未初始化的变量，因此无法可靠地重现。
local s = string.rep("\n", 2^24)
print(load(function () return s end))
补丁
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);
}
示例
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
补丁
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++)
示例
function f() f() end f() -- it takes too long before a "stack overflow" error
补丁
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;
}
示例
-- only with Lua compiled in debug mode
print({} .. 2)
补丁
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");
}
示例
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'
补丁
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;
}
}
示例
-- When you call 'luac -l' over this chunk, it chokes the output s="Lorem ipsum dolor sit amet, consectetur, "
补丁
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");
示例：此错误很难发生（也很难重现），因为它取决于 GC 在解析具有长标识符（大于 40 个字符）的源代码时以非常特殊的方式运行。
补丁
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。
补丁
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);
示例
-- should print 'true' print(coroutine.resume(coroutine.create(function() coroutine.resume(coroutine.running()) coroutine.yield() end)))
补丁
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--;
示例
print(string.find(string.rep("a", 2^20), string.rep(".?", 2^20)))
pcall 可能不会恢复先前的错误函数。
示例
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
补丁
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? */
示例：请参见 https://lua-users.lua.ac.cn/lists/lua-l/2012-08/msg00149.html。
补丁
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 和 loadfile 会返回错误结果。
示例
f = load(string.dump(function () return 1 end), nil, "b", {})
print(type(f)) --> table (should be function)
补丁
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);
}
示例
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
补丁
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));
示例
print(0xE+1)
补丁
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? */
示例
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
补丁
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。
示例
coroutine.wrap(function() print(pcall(pcall,pcall,pcall,pcall,pcall,error,3)) end)()
补丁
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);
示例
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
示例：在 C 中，设置一个仅让步的行钩子，然后调用任何 Lua 函数。您将得到一个无限让步循环。
这是 Lua 5.1 的最后一个版本。稍后报告的错误很可能已在 Lua 5.2 中修复。
src/Makefile 中的注释不可移植。
示例：在一些 mingw 系统上编译 Lua 时会发生此故障；它似乎不会影响其他系统。
补丁
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) $@
示例
load(function () print("called"); return nil end)
--> called
--> called (should be called only once!)
补丁
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;
}
解决方案：若要避免运行来自不受信任来源的预编译代码，如果流中的第一个字节是转义字符（十进制 27），则引发错误。
示例
function lunpack(i, ...)
if i == 0 then
return ...
else
return lunpack(i-1, 1, ...)
end
end
现在，如果 C 使用一个巨大的 n 调用 lunpack(n)，它可能会在堆栈中结束太多值，并混淆其堆栈索引。
示例
print(((1 or false) and true) or false) --> 1, but should be 'true'
补丁：（部分解决方案；另请参见 9）
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 可能会使对表的引用无效并尝试重新使用它。
示例
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)
补丁
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 不会检查它是否有一个参数。
示例
debug.getfenv() -- should raise an error
补丁
ldblib.c:
@@ -45,6 +45,7 @@
static int db_getfenv (lua_State *L) {
+ luaL_checkany(L, 1);
lua_getfenv(L, 1);
return 1;
}
示例：请参阅 https://lua-users.lua.ac.cn/lists/lua-l/2009-11/msg00463.html。
补丁
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 可能会将缓冲区作为参数获取。
示例
x = string.rep("x", 10000) .. "%d"
print(string.format(x)) -- gives wrong error message
补丁
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") 可能会返回垃圾。
示例
print(io.read("*n", "*n")) --<< enter "10 hi"
--> file (0x884420) nil
补丁
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 */
+ }
}
示例
print((('hi' or true) and true) or true)
--> hi (should be true)
print(((nil and nil) or false) and true)
--> nil (should be false)
补丁：（在 3 中的补丁之后应用）
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;
示例
meta={}
setmetatable(meta, meta)
meta.__newindex = function(t, key, value) print("set") end
o = setmetatable({}, meta)
o.x = 10 -- should print 'set'
补丁
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;
}
补丁
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 必须小于 -LUA_REGISTRYINDEX。
示例
j = 1e4
co = coroutine.create(function()
t = {}
for i = 1, j do t[i] = i end
return unpack(t)
end)
print(coroutine.resume(co))
补丁
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 推送元素时不确保堆栈大小。
示例：此错误在没有内部断言的情况下无法检测到。
补丁
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 对于较大的“size”可能出现算术溢出。
示例
print(unpack({1,2,3}, 0, 2^31-3))
补丁
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可能会因算术溢出而崩溃。
示例
print(unpack({1,2,3}, 2^31-1, 2^31-1))
补丁
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;
}
示例
a = string.dump(function()return;end) a = a:gsub(string.char(30,37,122,128), string.char(34,0,0), 1) loadstring(a)()
补丁
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: {
示例
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
补丁
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;
}
示例
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)))
补丁
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;
示例
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)
补丁
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 会与某些超出范围的负索引混淆。
示例
print(string.byte("abc", -5)) --> 97 98 99 (should print nothing)
补丁
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;
}
示例
collectgarbage("setpause", 100) -- small value
collectgarbage("setstepmul", 2000) -- large value
collectgarbage("step",0)
补丁
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 可能会更改 C 函数的环境。
示例
pcall(module, "xuxu") assert(debug.getfenv(pcall) == xuxu)
补丁
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 错误。
示例
/* in luaconf.h */
#define LUAI_USER_ALIGNMENT_T union { char b[32]; }
补丁
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 和 -false 生成的代码错误。
示例
print(-nil)
补丁
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;
补丁
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;
示例
a = function(a) coroutine.wrap(a)(a) end a(a)
补丁：所有线程应共享“nCcalls”计数器。（也就是说，它应在“global_State”结构中声明，而不是在“lua_State”中声明。）
示例
a = nil; a = (1)..a
补丁
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");
}
补丁
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);
示例
$ 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", ""))'
补丁
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 */
示例
lua -ltemp (assuming temp.lua has an error)
补丁
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 可能会失控。
示例
x = string.rep('a', 10000) .. string.rep('b', 10000)
print(#string.gsub(x, 'b'))
补丁
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 会移除表的最后一个元素。
示例
a = {1,2,3}
table.remove(a, 4)
print(a[3]) --> nil (should be 3)
补丁
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，可能会崩溃。
示例
> debug.setfenv(3, {})
补丁
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;
示例
> error(coroutine.create(function() end))
补丁
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 可能会溢出线程的堆栈。
示例
a = coroutine.create(function() yield() end) coroutine.resume(a) debug.sethook(a) -- may overflow the stack of 'a'
补丁
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));
示例
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)
补丁
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++;
}
示例
local Var local function main() NoSuchName (function() Var=0 end) end main()错误消息为尝试调用未赋值“Var”（一个 nil 值）。它应为尝试调用全局“NoSuchName”（一个 nil 值）。
补丁
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("%") 可能会读取字符串后面的内容。
示例
print(string.format("%"))
补丁
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 会抛出一个错误。
示例
print(os.date(""))
补丁
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 接受无效的首个参数。
示例
setfenv(nil, {}) -- should throw an error
补丁
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);
示例
-- 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, ???
补丁
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;
+ }
}
}
示例
function f (a)
a=nil
return a
end
print(f("test"))
补丁
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;
+ }
}
}
}
示例
a = {}
setmetatable(a, {__concat = function (a,b) print(type(a), type(b)) end})
a = 4 .. a
补丁
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 是一个库，不应访问 Lua 内部（通过 lobject.h）。
示例：该错误对外部行为没有影响。
补丁：在 loadlib.c 中，将所有 luaO_pushfstring 的出现更改为 lua_pushfstring。
示例
print(false or 0) -- on 16-bit machines
补丁
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 可能会产生错误的错误消息。
示例
getmetatable(io.stdin).__gc() --> bad argument #1 to '__gc' (FILE* expected, got table)
补丁
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 */
}
补丁：最简单的解决方案是使用带有 D3DCREATE_FPU_PRESERVE 标志的 DirectX。否则，可以将 luaconf.h 中的 lua_number2int 的定义更改为以下内容
#define lua_number2int(i,d) __asm fld d __asm fistp i
string.formatE 中的选项 '%q' 未正确处理 '\r'。
示例
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)
补丁
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 和 luaL_dostring 应返回块返回的所有值。
补丁
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)))
补丁
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;
示例
co = coroutine.create(function () coroutine.yield() end) debug.sethook(co, function() end, "lr") coroutine.resume(co) coroutine.resume(co)
补丁
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));
}
这是 Lua 5.0 的最后一个版本。稍后报告的错误很可能已在 Lua 5.1 中修复。
示例
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)
补丁
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 和 lua_setupvalue 不检查索引是否太小。
示例
debug.getupvalue(function() end, 0)
补丁
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;
示例
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
补丁
lgc.c:
221,224c221,222
< if (!u->marked) {
< markobject(st, &u->value);
< u->marked = 1;
< }
---
> markobject(st, u->v);
> u->marked = 1;
rawset 和 rawget 不忽略额外的参数。
示例
a = {}
rawset(a, 1, 2, 3)
print(a[1], a[2]) -- should be 2 and nil
补丁
lbaselib.c: 175a176 > lua_settop(L, 2); 183a185 > lua_settop(L, 3);
示例
a = {}
print(gcinfo())
for i = 1, 10000 do
a[i] = setmetatable({}, {__mode = "v"})
end
collectgarbage()
a = nil
collectgarbage()
print(gcinfo())
补丁
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;
}
示例
-- should print false, but prints nil print(not not (nil and 4))
io.popen 创建）可能会导致 Lua 崩溃。
示例
f = io.popen("ls")
f:close()
lua_closethread 仅存在于手册中。
解决方案：手册有误：线程受垃圾回收影响。
示例
function co_func (current_co) coroutine.resume(co) end co = coroutine.create(co_func) coroutine.resume(co) coroutine.resume(co) --> crash
补丁
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 无法在没有文件的情况下调用（导致崩溃）。
示例
> io.stdin.close() -- correct call should be io.stdin:close()
补丁
liolib.c:
161c161
< if (lua_isnone(L, 1)) {
---
> if (lua_isnone(L, 1) && lua_type(L, lua_upvalueindex(1)) == LUA_TTABLE) {
示例：必须在 lua.c 中进行更改并定义 lua_assert 才能重新编译 Lua
lua.c: 381a382 > lua_checkstack(l, 1000);
补丁
lgc.c: 247c247 < if (!(ci->state & CI_C) && lim < ci->top) --- > if (lim < ci->top)
示例
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)
补丁
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));
示例
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
补丁
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 中的缓冲区溢出。
示例
print{} -- on an AS400 machine
补丁
liolib.c: 178c178 < char buff[32]; --- > char buff[128]; lbaselib.c: 327c327 < char buff[64]; --- > char buff[128];
local function 不会增加栈大小。
示例
-- must run this with precompiled code local a,b,c local function d () end
补丁
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;
示例
如下设置挂钩。在未设置计数挂钩的情况下使用正计数很奇怪，但没有错。
lua_sethook(L, my_hook, LUA_MASKLINE | LUA_MASKRET, 1);
补丁
lvm.c:
69c69
< if (mask > LUA_MASKLINE) { /* instruction-hook set? */
---
> if (mask & LUA_MASKCOUNT) { /* instruction-hook set? */
dofile 会消耗一个返回值。
示例
a,b = dofile() --< here you enter `return 1,2,3 <eof>' print(a,b) --> 2 3 (should be 1 and 2)
补丁
lbaselib.c: 313a314 > int n = lua_gettop(L); 317c318 < return lua_gettop(L) - 1; --- > return lua_gettop(L) - n;
lua_getupvalue 和 lua_setupvalue 不会检查索引是否太小。
rawset 和 rawget 不会忽略额外的参数。
Lua 4.0 中的大多数错误已在 Lua 4.0.1 及更高版本中修复。
lua_pushuserdata(L,NULL) 不起作用。
while 1 dostring[[print('hello\n')]] end 永远不会回收内存。
ULONG_MAX>>10 可能不适合放入 int。