BUG: string concatenation may cause arithmetic overflow, leading

to a buffer overflow.
This commit is contained in:
Roberto Ierusalimschy
2004-06-08 13:23:58 -03:00
parent 2b2d8ecd7a
commit 9b854e6dbc
2 changed files with 40 additions and 3 deletions

36
bugs
View File

@@ -633,3 +633,39 @@ patch = [[
]],
}
-----------------------------------------------------------------
-- Lua 5.0.2
Bug{
what = [[string concatenation may cause arithmetic overflow, leading
to a buffer overflow]],
report = [[Rici Lake, 20/05/2004]],
example = [[
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)
]],
patch = [[
* lvm.c:
329c329,331
< tl += tsvalue(top-n-1)->tsv.len;
---
> size_t l = tsvalue(top-n-1)->tsv.len;
> if (l >= MAX_SIZET - tl) luaG_runerror(L, "string length overflow");
> tl += l;
332d333
< if (tl > MAX_SIZET) luaG_runerror(L, "string size overflow");
]]
}