ilusha/lua
1
0
Fork 0
mirror of https://github.com/lua/lua synced 2026-09-26 16:17:11 +03:00
Code Issues Projects Releases Packages Wiki Activity Actions

Bug: wrong initialization in result from 'gmatch'

Browse source 
Function returned by 'string.gmatch' can be left in an inconsistent
state after an error.
This commit is contained in:
Roberto Ierusalimschy 2026-04-01 15:01:58 -03:00
parent f1bb2773bb
commit efddc2309c
2 changed files with 18 additions and 2 deletions
Download patch file Download diff file Expand all files Collapse all files

10
lstrlib.c
View file

@ -757,19 +757,25 @@ static int nospecials (const char *p, size_t l) {
} }
/*
** Prepare state for matches. These fields are not affected by each match.
*/
static void prepstate (MatchState *ms, lua_State *L, static void prepstate (MatchState *ms, lua_State *L,
const char *s, size_t ls, const char *p, size_t lp) { const char *s, size_t ls, const char *p, size_t lp) {
ms->L = L; ms->L = L;
ms->matchdepth = MAXCCALLS;
ms->src_init = s; ms->src_init = s;
ms->src_end = s + ls; ms->src_end = s + ls;
ms->p_end = p + lp; ms->p_end = p + lp;
} }
/*
** (Re)prepare state for a match, setting fields that change during
** each match.
*/
static void reprepstate (MatchState *ms) { static void reprepstate (MatchState *ms) {
ms->matchdepth = MAXCCALLS;
ms->level = 0; ms->level = 0;
lua_assert(ms->matchdepth == MAXCCALLS);
} }

10
testes/pm.lua
View file

@ -347,6 +347,16 @@ do -- init parameter in gmatch
end end
do -- bug since 5.3
local N = 20000
local iter = string.gmatch(string.rep("a", N), string.rep("a?", N))
pcall(iter) -- error for pattern too complex
-- calling function again found recursion count ('matchdepth') equal
-- to -1, so it did not detect next C-stack overflow
pcall(iter)
end
-- tests for `%f' (`frontiers') -- tests for `%f' (`frontiers')
assert(string.gsub("aaa aa a aaa a", "%f[%w]a", "x") == "xaa xa x xaa x") assert(string.gsub("aaa aa a aaa a", "%f[%w]a", "x") == "xaa xa x xaa x")