Re: [PATCH] fat: Read buffer overflow

From: Pekka Enberg
Date: Sat Aug 08 2009 - 06:12:40 EST


On Sat, 2009-08-08 at 19:10 +0900, OGAWA Hirofumi wrote:
> Pekka Enberg <penberg@xxxxxxxxxxxxxx> writes:
>
> > Yes, but we pass "ulen" to vfat_is_used_badchars(). The value of
> > "ulen" is a returned in the "longlen" argument of xlate_to_uni() which
> > in turn is calculated as follows for the UTF-8 case:
> >
> > int name_len = strlen(name);
> > *outlen = utf8s_to_utf16s(name, PATH_MAX, (wchar_t *) outname);
> > *outlen -= (name_len - len);
> > *longlen = *outlen;
> >
> > Maybe "*outlen" can never be negative because of some invariants that
> > I don't see but it's so non-obvious to me that I'd like to see the
> > explicit check in vfat_is_used_badchars().
>
> Ah, good point. Sorry, I was looking my tree. I'm going to submit the
> attached patch on next merge window.
>
> Is this enough for it?

Fine by me!

Pekka

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/