On Fri, 2013-12-20 at 15:46 +0800, Wenliang Fan wrote: > The local variable 'pos' comes from userspace. If a large number was > passed, there would be an integer overflow in the following line: > pos += n; >
What about check before enter into the cycle? If you are talking about possible huge number then you can receive huge number from userspace before entering in the cycle. Thanks, Vyacheslav Dubeyko. > Signed-off-by: Wenliang Fan <[email protected]> > --- > fs/nilfs2/ioctl.c | 7 ++++++- > 1 file changed, 6 insertions(+), 1 deletion(-) > > diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c > index b44bdb2..b2bac9a 100644 > --- a/fs/nilfs2/ioctl.c > +++ b/fs/nilfs2/ioctl.c > @@ -90,8 +90,13 @@ static int nilfs_ioctl_wrap_copy(struct the_nilfs *nilfs, > total += nr; > if ((size_t)nr < n) > break; > - if (pos == ppos) > + if (pos == ppos) { > + if (pos > ULONG_MAX - n) { > + ret = -EINVAL; > + break; > + } > pos += n; > + } > } > argv->v_nmembs = total; > -- To unsubscribe from this list: send the line "unsubscribe linux-nilfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
