From: Jozsef Kadlecsik Date: Tue, 8 Mar 2016 19:29:10 +0000 (+0100) Subject: netfilter: ipset: Check IPSET_ATTR_ETHER netlink attribute length X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=d8aacd87180141ff6b812b53de77a4336e87c91a;p=openwrt%2Fstaging%2Fblogic.git netfilter: ipset: Check IPSET_ATTR_ETHER netlink attribute length 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 Signed-off-by: Jozsef Kadlecsik --- diff --git a/net/netfilter/ipset/ip_set_bitmap_ipmac.c b/net/netfilter/ipset/ip_set_bitmap_ipmac.c index 29dde208381d..9a065f672d3a 100644 --- a/net/netfilter/ipset/ip_set_bitmap_ipmac.c +++ b/net/netfilter/ipset/ip_set_bitmap_ipmac.c @@ -267,6 +267,8 @@ bitmap_ipmac_uadt(struct ip_set *set, struct nlattr *tb[], e.id = ip_to_id(map, ip); if (tb[IPSET_ATTR_ETHER]) { + if (nla_len(tb[IPSET_ATTR_ETHER]) != ETH_ALEN) + return -IPSET_ERR_PROTOCOL; memcpy(e.ether, nla_data(tb[IPSET_ATTR_ETHER]), ETH_ALEN); e.add_mac = 1; } diff --git a/net/netfilter/ipset/ip_set_hash_mac.c b/net/netfilter/ipset/ip_set_hash_mac.c index f1e7d2c0f685..8f004edad396 100644 --- a/net/netfilter/ipset/ip_set_hash_mac.c +++ b/net/netfilter/ipset/ip_set_hash_mac.c @@ -110,7 +110,8 @@ hash_mac4_uadt(struct ip_set *set, struct nlattr *tb[], if (tb[IPSET_ATTR_LINENO]) *lineno = nla_get_u32(tb[IPSET_ATTR_LINENO]); - if (unlikely(!tb[IPSET_ATTR_ETHER])) + 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);