From d22bf6a9bd216523e3f58195282be12d9da7fd33 Mon Sep 17 00:00:00 2001 From: the-Chain-Warden-thresh <18302010006@fudan.edu.cn> Date: Thu, 8 Feb 2024 03:53:05 +0800 Subject: [PATCH] LUA: Backport CVE-2020-24370's patch CVE-2020-24370 is a security vulnerability in lua. Although the CVE description in CVE-2020-24370 said that this CVE only affected lua 5.4.0, according to lua this CVE actually existed since lua 5.2. The root cause of this CVE is the negation overflow that occurs when you try to take the negative of 0x80000000. Thus, this CVE also exists in openzfs. Try to backport the fix to the lua in openzfs since the original fix is for 5.4 and several functions have been changed. https://github.com/advisories/GHSA-gfr4-c37g-mm3v https://nvd.nist.gov/vuln/detail/CVE-2020-24370 https://www.lua.org/bugs.html#5.4.0-11 https://github.com/lua/lua/commit/a585eae6e7ada1ca9271607a4f48dfb1786 Reviewed-by: Tony Hutter Reviewed-by: Brian Behlendorf Signed-off-by: ChenHao Lu <18302010006@fudan.edu.cn> Closes #15847 --- module/lua/ldebug.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/module/lua/ldebug.c b/module/lua/ldebug.c index 0092474c7..23e321bb1 100644 --- a/module/lua/ldebug.c +++ b/module/lua/ldebug.c @@ -111,10 +111,11 @@ static const char *upvalname (Proto *p, int uv) { static const char *findvararg (CallInfo *ci, int n, StkId *pos) { int nparams = clLvalue(ci->func)->p->numparams; - if (n >= ci->u.l.base - ci->func - nparams) + int nvararg = cast_int(ci->u.l.base - ci->func) - nparams; + if (n <= -nvararg) return NULL; /* no such vararg */ else { - *pos = ci->func + nparams + n; + *pos = ci->func + nparams - n; return "(*vararg)"; /* generic name for any vararg */ } } @@ -126,7 +127,7 @@ static const char *findlocal (lua_State *L, CallInfo *ci, int n, StkId base; if (isLua(ci)) { if (n < 0) /* access to vararg values? */ - return findvararg(ci, -n, pos); + return findvararg(ci, n, pos); else { base = ci->u.l.base; name = luaF_getlocalname(ci_func(ci)->p, n, currentpc(ci));