mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-25 02:09:42 +00:00
![Jozsef Kadlecsik](/assets/img/avatar_default.png)
Julia Lawall pointed out that IPSET_ATTR_ETHER netlink attribute length was not checked explicitly, just for the maximum possible size. Malicious netlink clients could send shorter attribute and thus resulting a kernel read after the buffer. The patch adds the explicit length checkings. Reported-by: Julia Lawall <julia.lawall@lip6.fr> Signed-off-by: Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
174 lines
4.6 KiB
C
174 lines
4.6 KiB
C
/* Copyright (C) 2014 Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
|
|
/* Kernel module implementing an IP set type: the hash:mac type */
|
|
|
|
#include <linux/jhash.h>
|
|
#include <linux/module.h>
|
|
#include <linux/etherdevice.h>
|
|
#include <linux/skbuff.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/if_ether.h>
|
|
#include <net/netlink.h>
|
|
|
|
#include <linux/netfilter.h>
|
|
#include <linux/netfilter/ipset/ip_set.h>
|
|
#include <linux/netfilter/ipset/ip_set_hash.h>
|
|
|
|
#define IPSET_TYPE_REV_MIN 0
|
|
#define IPSET_TYPE_REV_MAX 0
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Jozsef Kadlecsik <kadlec@blackhole.kfki.hu>");
|
|
IP_SET_MODULE_DESC("hash:mac", IPSET_TYPE_REV_MIN, IPSET_TYPE_REV_MAX);
|
|
MODULE_ALIAS("ip_set_hash:mac");
|
|
|
|
/* Type specific function prefix */
|
|
#define HTYPE hash_mac
|
|
|
|
/* Member elements */
|
|
struct hash_mac4_elem {
|
|
/* Zero valued IP addresses cannot be stored */
|
|
union {
|
|
unsigned char ether[ETH_ALEN];
|
|
__be32 foo[2];
|
|
};
|
|
};
|
|
|
|
/* Common functions */
|
|
|
|
static inline bool
|
|
hash_mac4_data_equal(const struct hash_mac4_elem *e1,
|
|
const struct hash_mac4_elem *e2,
|
|
u32 *multi)
|
|
{
|
|
return ether_addr_equal(e1->ether, e2->ether);
|
|
}
|
|
|
|
static inline bool
|
|
hash_mac4_data_list(struct sk_buff *skb, const struct hash_mac4_elem *e)
|
|
{
|
|
if (nla_put(skb, IPSET_ATTR_ETHER, ETH_ALEN, e->ether))
|
|
goto nla_put_failure;
|
|
return false;
|
|
|
|
nla_put_failure:
|
|
return true;
|
|
}
|
|
|
|
static inline void
|
|
hash_mac4_data_next(struct hash_mac4_elem *next,
|
|
const struct hash_mac4_elem *e)
|
|
{
|
|
}
|
|
|
|
#define MTYPE hash_mac4
|
|
#define HOST_MASK 32
|
|
#define IP_SET_EMIT_CREATE
|
|
#define IP_SET_PROTO_UNDEF
|
|
#include "ip_set_hash_gen.h"
|
|
|
|
/* Zero valued element is not supported */
|
|
static const unsigned char invalid_ether[ETH_ALEN] = { 0 };
|
|
|
|
static int
|
|
hash_mac4_kadt(struct ip_set *set, const struct sk_buff *skb,
|
|
const struct xt_action_param *par,
|
|
enum ipset_adt adt, struct ip_set_adt_opt *opt)
|
|
{
|
|
ipset_adtfn adtfn = set->variant->adt[adt];
|
|
struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
|
|
struct ip_set_ext ext = IP_SET_INIT_KEXT(skb, opt, set);
|
|
|
|
/* MAC can be src only */
|
|
if (!(opt->flags & IPSET_DIM_ONE_SRC))
|
|
return 0;
|
|
|
|
if (skb_mac_header(skb) < skb->head ||
|
|
(skb_mac_header(skb) + ETH_HLEN) > skb->data)
|
|
return -EINVAL;
|
|
|
|
ether_addr_copy(e.ether, eth_hdr(skb)->h_source);
|
|
if (memcmp(e.ether, invalid_ether, ETH_ALEN) == 0)
|
|
return -EINVAL;
|
|
return adtfn(set, &e, &ext, &opt->ext, opt->cmdflags);
|
|
}
|
|
|
|
static int
|
|
hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[],
|
|
enum ipset_adt adt, u32 *lineno, u32 flags, bool retried)
|
|
{
|
|
ipset_adtfn adtfn = set->variant->adt[adt];
|
|
struct hash_mac4_elem e = { { .foo[0] = 0, .foo[1] = 0 } };
|
|
struct ip_set_ext ext = IP_SET_INIT_UEXT(set);
|
|
int ret;
|
|
|
|
if (tb[IPSET_ATTR_LINENO])
|
|
*lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]);
|
|
|
|
if (unlikely(!tb[IPSET_ATTR_ETHER] ||
|
|
nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN))
|
|
return -IPSET_ERR_PROTOCOL;
|
|
|
|
ret = ip_set_get_extensions(set, tb, &ext);
|
|
if (ret)
|
|
return ret;
|
|
ether_addr_copy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]));
|
|
if (memcmp(e.ether, invalid_ether, ETH_ALEN) == 0)
|
|
return -IPSET_ERR_HASH_ELEM;
|
|
|
|
return adtfn(set, &e, &ext, &ext, flags);
|
|
}
|
|
|
|
static struct ip_set_type hash_mac_type __read_mostly = {
|
|
.name = "hash:mac",
|
|
.protocol = IPSET_PROTOCOL,
|
|
.features = IPSET_TYPE_MAC,
|
|
.dimension = IPSET_DIM_ONE,
|
|
.family = NFPROTO_UNSPEC,
|
|
.revision_min = IPSET_TYPE_REV_MIN,
|
|
.revision_max = IPSET_TYPE_REV_MAX,
|
|
.create = hash_mac_create,
|
|
.create_policy = {
|
|
[IPSET_ATTR_HASHSIZE] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_MAXELEM] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_PROBES] = { .type = NLA_U8 },
|
|
[IPSET_ATTR_RESIZE] = { .type = NLA_U8 },
|
|
[IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_CADT_FLAGS] = { .type = NLA_U32 },
|
|
},
|
|
.adt_policy = {
|
|
[IPSET_ATTR_ETHER] = { .type = NLA_BINARY,
|
|
.len = ETH_ALEN },
|
|
[IPSET_ATTR_TIMEOUT] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_LINENO] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_BYTES] = { .type = NLA_U64 },
|
|
[IPSET_ATTR_PACKETS] = { .type = NLA_U64 },
|
|
[IPSET_ATTR_COMMENT] = { .type = NLA_NUL_STRING,
|
|
.len = IPSET_MAX_COMMENT_SIZE },
|
|
[IPSET_ATTR_SKBMARK] = { .type = NLA_U64 },
|
|
[IPSET_ATTR_SKBPRIO] = { .type = NLA_U32 },
|
|
[IPSET_ATTR_SKBQUEUE] = { .type = NLA_U16 },
|
|
},
|
|
.me = THIS_MODULE,
|
|
};
|
|
|
|
static int __init
|
|
hash_mac_init(void)
|
|
{
|
|
return ip_set_type_register(&hash_mac_type);
|
|
}
|
|
|
|
static void __exit
|
|
hash_mac_fini(void)
|
|
{
|
|
rcu_barrier();
|
|
ip_set_type_unregister(&hash_mac_type);
|
|
}
|
|
|
|
module_init(hash_mac_init);
|
|
module_exit(hash_mac_fini);
|