Re: unused code in net/netfilter/ipset/ip_set_bitmap_ipmac.c

Hi,

On Mon, 29 Feb 2016, Julia Lawall wrote:

The file net/netfilter/ipset/ip_set_bitmap_ipmac.c seems to contain a lot
of static functions that are not used in the file:

bitmap_ipmac_add_timeout
bitmap_ipmac_do_add
bitmap_ipmac_do_del
bitmap_ipmac_do_head
bitmap_ipmac_do_list
bitmap_ipmac_do_test
bitmap_ipmac_gc_test
bitmap_ipmac_is_filled
bitmap_ipmac_kadt
bitmap_ipmac_same_set
bitmap_ipmac_uadt

Have I overooked something?

Yes: the file includes ip_set_bitmap_gen.h in which all those functions 
are used.
 

I was looking at this code, with Daniel Borkmann, because there seems to
be a bug in the function bitmap_ipmac_uadt:

	if (tb[IPSET_ATTR_ETHER]) {
                memcpy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]), ETH_ALEN);
                e.add_mac = 1;
        }

Later in the same file, there is:

static struct ip_set_type bitmap_ipmac_type = {
	...
        .adt_policy     = {
		...
		[IPSET_ATTR_ETHER]      = { .type = NLA_BINARY,
                                            .len  = ETH_ALEN },
		...},
	...
};

The type NLA_BINARY indicates that the length is a maximum possible
length, and thus a check of the actual length is needed before the memcpy.

You are right here (and the similar spotting in ip_set_hash_mac.c) - I'll 
prepare a patch and submit it.

Best regards,
Jozsef
-
E-mail  : kadlec@blackhole.kfki.hu, kadlecsik.jozsef@wigner.mta.hu
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Address : Wigner Research Centre for Physics, Hungarian Academy of Sciences
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