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Diffstat (limited to 'net/netfilter/nfnetlink.c')
-rw-r--r--net/netfilter/nfnetlink.c222
1 files changed, 199 insertions, 23 deletions
diff --git a/net/netfilter/nfnetlink.c b/net/netfilter/nfnetlink.c
index d578ec25171..c138b8fbe28 100644
--- a/net/netfilter/nfnetlink.c
+++ b/net/netfilter/nfnetlink.c
@@ -24,10 +24,9 @@
#include <linux/skbuff.h>
#include <asm/uaccess.h>
#include <net/sock.h>
-#include <net/netlink.h>
#include <linux/init.h>
-#include <linux/netlink.h>
+#include <net/netlink.h>
#include <linux/netfilter/nfnetlink.h>
MODULE_LICENSE("GPL");
@@ -62,10 +61,13 @@ void nfnl_unlock(__u8 subsys_id)
}
EXPORT_SYMBOL_GPL(nfnl_unlock);
-static struct mutex *nfnl_get_lock(__u8 subsys_id)
+#ifdef CONFIG_PROVE_LOCKING
+int lockdep_nfnl_is_held(u8 subsys_id)
{
- return &table[subsys_id].mutex;
+ return lockdep_is_held(&table[subsys_id].mutex);
}
+EXPORT_SYMBOL_GPL(lockdep_nfnl_is_held);
+#endif
int nfnetlink_subsys_register(const struct nfnetlink_subsystem *n)
{
@@ -118,22 +120,30 @@ int nfnetlink_has_listeners(struct net *net, unsigned int group)
}
EXPORT_SYMBOL_GPL(nfnetlink_has_listeners);
-int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 pid,
+struct sk_buff *nfnetlink_alloc_skb(struct net *net, unsigned int size,
+ u32 dst_portid, gfp_t gfp_mask)
+{
+ return netlink_alloc_skb(net->nfnl, size, dst_portid, gfp_mask);
+}
+EXPORT_SYMBOL_GPL(nfnetlink_alloc_skb);
+
+int nfnetlink_send(struct sk_buff *skb, struct net *net, u32 portid,
unsigned int group, int echo, gfp_t flags)
{
- return nlmsg_notify(net->nfnl, skb, pid, group, echo, flags);
+ return nlmsg_notify(net->nfnl, skb, portid, group, echo, flags);
}
EXPORT_SYMBOL_GPL(nfnetlink_send);
-int nfnetlink_set_err(struct net *net, u32 pid, u32 group, int error)
+int nfnetlink_set_err(struct net *net, u32 portid, u32 group, int error)
{
- return netlink_set_err(net->nfnl, pid, group, error);
+ return netlink_set_err(net->nfnl, portid, group, error);
}
EXPORT_SYMBOL_GPL(nfnetlink_set_err);
-int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u_int32_t pid, int flags)
+int nfnetlink_unicast(struct sk_buff *skb, struct net *net, u32 portid,
+ int flags)
{
- return netlink_unicast(net->nfnl, skb, pid, flags);
+ return netlink_unicast(net->nfnl, skb, portid, flags);
}
EXPORT_SYMBOL_GPL(nfnetlink_unicast);
@@ -145,11 +155,8 @@ static int nfnetlink_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
const struct nfnetlink_subsystem *ss;
int type, err;
- if (!ns_capable(net->user_ns, CAP_NET_ADMIN))
- return -EPERM;
-
/* All the messages must at least contain nfgenmsg */
- if (nlh->nlmsg_len < NLMSG_LENGTH(sizeof(struct nfgenmsg)))
+ if (nlmsg_len(nlh) < sizeof(struct nfgenmsg))
return 0;
type = nlh->nlmsg_type;
@@ -177,7 +184,7 @@ replay:
}
{
- int min_len = NLMSG_SPACE(sizeof(struct nfgenmsg));
+ int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
struct nlattr *attr = (void *)nlh + min_len;
@@ -199,7 +206,7 @@ replay:
rcu_read_unlock();
nfnl_lock(subsys_id);
if (rcu_dereference_protected(table[subsys_id].subsys,
- lockdep_is_held(nfnl_get_lock(subsys_id))) != ss ||
+ lockdep_is_held(&table[subsys_id].mutex)) != ss ||
nfnetlink_find_client(type, ss) != nc)
err = -EAGAIN;
else if (nc->call)
@@ -215,25 +222,194 @@ replay:
}
}
+static void nfnetlink_rcv_batch(struct sk_buff *skb, struct nlmsghdr *nlh,
+ u_int16_t subsys_id)
+{
+ struct sk_buff *nskb, *oskb = skb;
+ struct net *net = sock_net(skb->sk);
+ const struct nfnetlink_subsystem *ss;
+ const struct nfnl_callback *nc;
+ bool success = true, done = false;
+ int err;
+
+ if (subsys_id >= NFNL_SUBSYS_COUNT)
+ return netlink_ack(skb, nlh, -EINVAL);
+replay:
+ nskb = netlink_skb_clone(oskb, GFP_KERNEL);
+ if (!nskb)
+ return netlink_ack(oskb, nlh, -ENOMEM);
+
+ nskb->sk = oskb->sk;
+ skb = nskb;
+
+ nfnl_lock(subsys_id);
+ ss = rcu_dereference_protected(table[subsys_id].subsys,
+ lockdep_is_held(&table[subsys_id].mutex));
+ if (!ss) {
+#ifdef CONFIG_MODULES
+ nfnl_unlock(subsys_id);
+ request_module("nfnetlink-subsys-%d", subsys_id);
+ nfnl_lock(subsys_id);
+ ss = rcu_dereference_protected(table[subsys_id].subsys,
+ lockdep_is_held(&table[subsys_id].mutex));
+ if (!ss)
+#endif
+ {
+ nfnl_unlock(subsys_id);
+ netlink_ack(skb, nlh, -EOPNOTSUPP);
+ return kfree_skb(nskb);
+ }
+ }
+
+ if (!ss->commit || !ss->abort) {
+ nfnl_unlock(subsys_id);
+ netlink_ack(skb, nlh, -EOPNOTSUPP);
+ return kfree_skb(skb);
+ }
+
+ while (skb->len >= nlmsg_total_size(0)) {
+ int msglen, type;
+
+ nlh = nlmsg_hdr(skb);
+ err = 0;
+
+ if (nlh->nlmsg_len < NLMSG_HDRLEN) {
+ err = -EINVAL;
+ goto ack;
+ }
+
+ /* Only requests are handled by the kernel */
+ if (!(nlh->nlmsg_flags & NLM_F_REQUEST)) {
+ err = -EINVAL;
+ goto ack;
+ }
+
+ type = nlh->nlmsg_type;
+ if (type == NFNL_MSG_BATCH_BEGIN) {
+ /* Malformed: Batch begin twice */
+ success = false;
+ goto done;
+ } else if (type == NFNL_MSG_BATCH_END) {
+ done = true;
+ goto done;
+ } else if (type < NLMSG_MIN_TYPE) {
+ err = -EINVAL;
+ goto ack;
+ }
+
+ /* We only accept a batch with messages for the same
+ * subsystem.
+ */
+ if (NFNL_SUBSYS_ID(type) != subsys_id) {
+ err = -EINVAL;
+ goto ack;
+ }
+
+ nc = nfnetlink_find_client(type, ss);
+ if (!nc) {
+ err = -EINVAL;
+ goto ack;
+ }
+
+ {
+ int min_len = nlmsg_total_size(sizeof(struct nfgenmsg));
+ u_int8_t cb_id = NFNL_MSG_TYPE(nlh->nlmsg_type);
+ struct nlattr *cda[ss->cb[cb_id].attr_count + 1];
+ struct nlattr *attr = (void *)nlh + min_len;
+ int attrlen = nlh->nlmsg_len - min_len;
+
+ err = nla_parse(cda, ss->cb[cb_id].attr_count,
+ attr, attrlen, ss->cb[cb_id].policy);
+ if (err < 0)
+ goto ack;
+
+ if (nc->call_batch) {
+ err = nc->call_batch(net->nfnl, skb, nlh,
+ (const struct nlattr **)cda);
+ }
+
+ /* The lock was released to autoload some module, we
+ * have to abort and start from scratch using the
+ * original skb.
+ */
+ if (err == -EAGAIN) {
+ ss->abort(skb);
+ nfnl_unlock(subsys_id);
+ kfree_skb(nskb);
+ goto replay;
+ }
+ }
+ack:
+ if (nlh->nlmsg_flags & NLM_F_ACK || err) {
+ /* We don't stop processing the batch on errors, thus,
+ * userspace gets all the errors that the batch
+ * triggers.
+ */
+ netlink_ack(skb, nlh, err);
+ if (err)
+ success = false;
+ }
+
+ msglen = NLMSG_ALIGN(nlh->nlmsg_len);
+ if (msglen > skb->len)
+ msglen = skb->len;
+ skb_pull(skb, msglen);
+ }
+done:
+ if (success && done)
+ ss->commit(skb);
+ else
+ ss->abort(skb);
+
+ nfnl_unlock(subsys_id);
+ kfree_skb(nskb);
+}
+
static void nfnetlink_rcv(struct sk_buff *skb)
{
- netlink_rcv_skb(skb, &nfnetlink_rcv_msg);
+ struct nlmsghdr *nlh = nlmsg_hdr(skb);
+ int msglen;
+
+ if (nlh->nlmsg_len < NLMSG_HDRLEN ||
+ skb->len < nlh->nlmsg_len)
+ return;
+
+ if (!netlink_net_capable(skb, CAP_NET_ADMIN)) {
+ netlink_ack(skb, nlh, -EPERM);
+ return;
+ }
+
+ if (nlh->nlmsg_type == NFNL_MSG_BATCH_BEGIN) {
+ struct nfgenmsg *nfgenmsg;
+
+ msglen = NLMSG_ALIGN(nlh->nlmsg_len);
+ if (msglen > skb->len)
+ msglen = skb->len;
+
+ if (nlh->nlmsg_len < NLMSG_HDRLEN ||
+ skb->len < NLMSG_HDRLEN + sizeof(struct nfgenmsg))
+ return;
+
+ nfgenmsg = nlmsg_data(nlh);
+ skb_pull(skb, msglen);
+ nfnetlink_rcv_batch(skb, nlh, nfgenmsg->res_id);
+ } else {
+ netlink_rcv_skb(skb, &nfnetlink_rcv_msg);
+ }
}
#ifdef CONFIG_MODULES
-static void nfnetlink_bind(int group)
+static int nfnetlink_bind(int group)
{
const struct nfnetlink_subsystem *ss;
int type = nfnl_group2type[group];
rcu_read_lock();
ss = nfnetlink_get_subsys(type);
- if (!ss) {
- rcu_read_unlock();
- request_module("nfnetlink-subsys-%d", type);
- return;
- }
rcu_read_unlock();
+ if (!ss)
+ request_module("nfnetlink-subsys-%d", type);
+ return 0;
}
#endif