lua5.3: backport CVE fix

[openwrt/staging/stintel.git] / package / utils / lua5.3 / patches-host / 200-CVE-2019-6706.patch

diff --git a/package/utils/lua5.3/patches-host/200-CVE-2019-6706.patch b/package/utils/lua5.3/patches-host/200-CVE-2019-6706.patch
new file mode 100644 (file)
index 0000000..8024d41
--- /dev/null
+++ b/package/utils/lua5.3/patches-host/200-CVE-2019-6706.patch
@@ -0,0 +1,51 @@
+From 89aee84cbc9224f638f3b7951b306d2ee8ecb71e Mon Sep 17 00:00:00 2001
+From: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
+Date: Wed, 27 Mar 2019 14:30:12 -0300
+Subject: [PATCH] Fixed bug in 'lua_upvaluejoin'
+
+Bug-fix: joining an upvalue with itself could cause a use-after-free
+crash.
+---
+ src/lapi.c   | 12 +++++------
+ 1 file changed, 41 insertions(+), 39 deletions(-)
+
+--- a/src/lapi.c
++++ b/src/lapi.c
+@@ -1254,13 +1254,12 @@ LUA_API const char *lua_setupvalue (lua_
+ }
+ 
+ 
+-static UpVal **getupvalref (lua_State *L, int fidx, int n, LClosure **pf) {
++static UpVal **getupvalref (lua_State *L, int fidx, int n) {
+   LClosure *f;
+   StkId fi = index2addr(L, fidx);
+   api_check(L, ttisLclosure(fi), "Lua function expected");
+   f = clLvalue(fi);
+   api_check(L, (1 <= n && n <= f->p->sizeupvalues), "invalid upvalue index");
+-  if (pf) *pf = f;
+   return &f->upvals[n - 1];  /* get its upvalue pointer */
+ }
+ 
+@@ -1269,7 +1268,7 @@ LUA_API void *lua_upvalueid (lua_State *
+   StkId fi = index2addr(L, fidx);
+   switch (ttype(fi)) {
+     case LUA_TLCL: {  /* lua closure */
+-      return *getupvalref(L, fidx, n, NULL);
++      return *getupvalref(L, fidx, n);
+     }
+     case LUA_TCCL: {  /* C closure */
+       CClosure *f = clCvalue(fi);
+@@ -1286,9 +1285,10 @@ LUA_API void *lua_upvalueid (lua_State *
+ 
+ LUA_API void lua_upvaluejoin (lua_State *L, int fidx1, int n1,
+                                             int fidx2, int n2) {
+-  LClosure *f1;
+-  UpVal **up1 = getupvalref(L, fidx1, n1, &f1);
+-  UpVal **up2 = getupvalref(L, fidx2, n2, NULL);
++  UpVal **up1 = getupvalref(L, fidx1, n1);
++  UpVal **up2 = getupvalref(L, fidx2, n2);
++  if (*up1 == *up2)
++    return;
+   luaC_upvdeccount(L, *up1);
+   *up1 = *up2;
+   (*up1)->refcount++;