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Diffstat (limited to 'net/netlink/af_netlink.c')
-rw-r--r--net/netlink/af_netlink.c131
1 files changed, 74 insertions, 57 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index 0c61b59175d..8df7f64c6db 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -168,16 +168,43 @@ int netlink_remove_tap(struct netlink_tap *nt)
}
EXPORT_SYMBOL_GPL(netlink_remove_tap);
+static bool netlink_filter_tap(const struct sk_buff *skb)
+{
+ struct sock *sk = skb->sk;
+ bool pass = false;
+
+ /* We take the more conservative approach and
+ * whitelist socket protocols that may pass.
+ */
+ switch (sk->sk_protocol) {
+ case NETLINK_ROUTE:
+ case NETLINK_USERSOCK:
+ case NETLINK_SOCK_DIAG:
+ case NETLINK_NFLOG:
+ case NETLINK_XFRM:
+ case NETLINK_FIB_LOOKUP:
+ case NETLINK_NETFILTER:
+ case NETLINK_GENERIC:
+ pass = true;
+ break;
+ }
+
+ return pass;
+}
+
static int __netlink_deliver_tap_skb(struct sk_buff *skb,
struct net_device *dev)
{
struct sk_buff *nskb;
+ struct sock *sk = skb->sk;
int ret = -ENOMEM;
dev_hold(dev);
nskb = skb_clone(skb, GFP_ATOMIC);
if (nskb) {
nskb->dev = dev;
+ nskb->protocol = htons((u16) sk->sk_protocol);
+
ret = dev_queue_xmit(nskb);
if (unlikely(ret > 0))
ret = net_xmit_errno(ret);
@@ -192,6 +219,9 @@ static void __netlink_deliver_tap(struct sk_buff *skb)
int ret;
struct netlink_tap *tmp;
+ if (!netlink_filter_tap(skb))
+ return;
+
list_for_each_entry_rcu(tmp, &netlink_tap_all, list) {
ret = __netlink_deliver_tap_skb(skb, tmp->dev);
if (unlikely(ret))
@@ -294,14 +324,14 @@ static void **alloc_pg_vec(struct netlink_sock *nlk,
{
unsigned int block_nr = req->nm_block_nr;
unsigned int i;
- void **pg_vec, *ptr;
+ void **pg_vec;
pg_vec = kcalloc(block_nr, sizeof(void *), GFP_KERNEL);
if (pg_vec == NULL)
return NULL;
for (i = 0; i < block_nr; i++) {
- pg_vec[i] = ptr = alloc_one_pg_vec_page(order);
+ pg_vec[i] = alloc_one_pg_vec_page(order);
if (pg_vec[i] == NULL)
goto err1;
}
@@ -595,7 +625,7 @@ static unsigned int netlink_poll(struct file *file, struct socket *sock,
* for dumps is performed here. A dump is allowed to continue
* if at least half the ring is unused.
*/
- while (nlk->cb != NULL && netlink_dump_space(nlk)) {
+ while (nlk->cb_running && netlink_dump_space(nlk)) {
err = netlink_dump(sk);
if (err < 0) {
sk->sk_err = err;
@@ -802,18 +832,6 @@ static void netlink_ring_set_copied(struct sock *sk, struct sk_buff *skb)
#define netlink_mmap_sendmsg(sk, msg, dst_portid, dst_group, siocb) 0
#endif /* CONFIG_NETLINK_MMAP */
-static void netlink_destroy_callback(struct netlink_callback *cb)
-{
- kfree_skb(cb->skb);
- kfree(cb);
-}
-
-static void netlink_consume_callback(struct netlink_callback *cb)
-{
- consume_skb(cb->skb);
- kfree(cb);
-}
-
static void netlink_skb_destructor(struct sk_buff *skb)
{
#ifdef CONFIG_NETLINK_MMAP
@@ -872,12 +890,12 @@ static void netlink_sock_destruct(struct sock *sk)
{
struct netlink_sock *nlk = nlk_sk(sk);
- if (nlk->cb) {
- if (nlk->cb->done)
- nlk->cb->done(nlk->cb);
+ if (nlk->cb_running) {
+ if (nlk->cb.done)
+ nlk->cb.done(&nlk->cb);
- module_put(nlk->cb->module);
- netlink_destroy_callback(nlk->cb);
+ module_put(nlk->cb.module);
+ kfree_skb(nlk->cb.skb);
}
skb_queue_purge(&sk->sk_receive_queue);
@@ -2350,7 +2368,8 @@ static int netlink_recvmsg(struct kiocb *kiocb, struct socket *sock,
skb_free_datagram(sk, skb);
- if (nlk->cb && atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
+ if (nlk->cb_running &&
+ atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
ret = netlink_dump(sk);
if (ret) {
sk->sk_err = ret;
@@ -2566,13 +2585,12 @@ static int netlink_dump(struct sock *sk)
int alloc_size;
mutex_lock(nlk->cb_mutex);
-
- cb = nlk->cb;
- if (cb == NULL) {
+ if (!nlk->cb_running) {
err = -EINVAL;
goto errout_skb;
}
+ cb = &nlk->cb;
alloc_size = max_t(int, cb->min_dump_alloc, NLMSG_GOODSIZE);
if (!netlink_rx_is_mmaped(sk) &&
@@ -2610,11 +2628,11 @@ static int netlink_dump(struct sock *sk)
if (cb->done)
cb->done(cb);
- nlk->cb = NULL;
- mutex_unlock(nlk->cb_mutex);
+ nlk->cb_running = false;
+ mutex_unlock(nlk->cb_mutex);
module_put(cb->module);
- netlink_consume_callback(cb);
+ consume_skb(cb->skb);
return 0;
errout_skb:
@@ -2632,59 +2650,51 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
struct netlink_sock *nlk;
int ret;
- cb = kzalloc(sizeof(*cb), GFP_KERNEL);
- if (cb == NULL)
- return -ENOBUFS;
-
/* Memory mapped dump requests need to be copied to avoid looping
* on the pending state in netlink_mmap_sendmsg() while the CB hold
* a reference to the skb.
*/
if (netlink_skb_is_mmaped(skb)) {
skb = skb_copy(skb, GFP_KERNEL);
- if (skb == NULL) {
- kfree(cb);
+ if (skb == NULL)
return -ENOBUFS;
- }
} else
atomic_inc(&skb->users);
- cb->dump = control->dump;
- cb->done = control->done;
- cb->nlh = nlh;
- cb->data = control->data;
- cb->module = control->module;
- cb->min_dump_alloc = control->min_dump_alloc;
- cb->skb = skb;
-
sk = netlink_lookup(sock_net(ssk), ssk->sk_protocol, NETLINK_CB(skb).portid);
if (sk == NULL) {
- netlink_destroy_callback(cb);
- return -ECONNREFUSED;
+ ret = -ECONNREFUSED;
+ goto error_free;
}
- nlk = nlk_sk(sk);
+ nlk = nlk_sk(sk);
mutex_lock(nlk->cb_mutex);
/* A dump is in progress... */
- if (nlk->cb) {
- mutex_unlock(nlk->cb_mutex);
- netlink_destroy_callback(cb);
+ if (nlk->cb_running) {
ret = -EBUSY;
- goto out;
+ goto error_unlock;
}
/* add reference of module which cb->dump belongs to */
- if (!try_module_get(cb->module)) {
- mutex_unlock(nlk->cb_mutex);
- netlink_destroy_callback(cb);
+ if (!try_module_get(control->module)) {
ret = -EPROTONOSUPPORT;
- goto out;
+ goto error_unlock;
}
- nlk->cb = cb;
+ cb = &nlk->cb;
+ memset(cb, 0, sizeof(*cb));
+ cb->dump = control->dump;
+ cb->done = control->done;
+ cb->nlh = nlh;
+ cb->data = control->data;
+ cb->module = control->module;
+ cb->min_dump_alloc = control->min_dump_alloc;
+ cb->skb = skb;
+
+ nlk->cb_running = true;
+
mutex_unlock(nlk->cb_mutex);
ret = netlink_dump(sk);
-out:
sock_put(sk);
if (ret)
@@ -2694,6 +2704,13 @@ out:
* signal not to send ACK even if it was requested.
*/
return -EINTR;
+
+error_unlock:
+ sock_put(sk);
+ mutex_unlock(nlk->cb_mutex);
+error_free:
+ kfree_skb(skb);
+ return ret;
}
EXPORT_SYMBOL(__netlink_dump_start);
@@ -2916,14 +2933,14 @@ static int netlink_seq_show(struct seq_file *seq, void *v)
struct sock *s = v;
struct netlink_sock *nlk = nlk_sk(s);
- seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %pK %-8d %-8d %-8lu\n",
+ seq_printf(seq, "%pK %-3d %-6u %08x %-8d %-8d %d %-8d %-8d %-8lu\n",
s,
s->sk_protocol,
nlk->portid,
nlk->groups ? (u32)nlk->groups[0] : 0,
sk_rmem_alloc_get(s),
sk_wmem_alloc_get(s),
- nlk->cb,
+ nlk->cb_running,
atomic_read(&s->sk_refcnt),
atomic_read(&s->sk_drops),
sock_i_ino(s)
generated by cgit v1.2.3-70-g09d2 (git 2.46.0) at 2024-12-23 17:39:05 +0000