提交 157ffffe 编写于 作者: F Florian Westphal 提交者: Pablo Neira Ayuso

netfilter: nfnetlink_cthelper: reject too large userspace allocation requests

Userspace should not abuse the kernel to store large amounts of data,
reject requests larger than the private area can accommodate.
Signed-off-by: NFlorian Westphal <fw@strlen.de>
Signed-off-by: NPablo Neira Ayuso <pablo@netfilter.org>
上级 dcf67740
......@@ -104,7 +104,7 @@ nfnl_cthelper_from_nlattr(struct nlattr *attr, struct nf_conn *ct)
if (help->helper->data_len == 0)
return -EINVAL;
memcpy(help->data, nla_data(attr), help->helper->data_len);
nla_memcpy(help->data, nla_data(attr), sizeof(help->data));
return 0;
}
......@@ -216,6 +216,7 @@ nfnl_cthelper_create(const struct nlattr * const tb[],
{
struct nf_conntrack_helper *helper;
struct nfnl_cthelper *nfcth;
unsigned int size;
int ret;
if (!tb[NFCTH_TUPLE] || !tb[NFCTH_POLICY] || !tb[NFCTH_PRIV_DATA_LEN])
......@@ -231,7 +232,12 @@ nfnl_cthelper_create(const struct nlattr * const tb[],
goto err1;
strncpy(helper->name, nla_data(tb[NFCTH_NAME]), NF_CT_HELPER_NAME_LEN);
helper->data_len = ntohl(nla_get_be32(tb[NFCTH_PRIV_DATA_LEN]));
size = ntohl(nla_get_be32(tb[NFCTH_PRIV_DATA_LEN]));
if (size > FIELD_SIZEOF(struct nf_conn_help, data)) {
ret = -ENOMEM;
goto err2;
}
helper->flags |= NF_CT_HELPER_F_USERSPACE;
memcpy(&helper->tuple, tuple, sizeof(struct nf_conntrack_tuple));
......
Markdown is supported
0% .
You are about to add 0 people to the discussion. Proceed with caution.
先完成此消息的编辑!
想要评论请 注册