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Diffstat (limited to 'net/netlink/af_netlink.c')
-rw-r--r--net/netlink/af_netlink.c76
1 files changed, 46 insertions, 30 deletions
diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c
index ff315351269f..7554803218a2 100644
--- a/net/netlink/af_netlink.c
+++ b/net/netlink/af_netlink.c
@@ -130,7 +130,7 @@ static const char *const nlk_cb_mutex_key_strings[MAX_LINKS + 1] = {
"nlk_cb_mutex-MAX_LINKS"
};
-static int netlink_dump(struct sock *sk);
+static int netlink_dump(struct sock *sk, bool lock_taken);
/* nl_table locking explained:
* Lookup and traversal are protected with an RCU read-side lock. Insertion
@@ -636,7 +636,7 @@ static struct proto netlink_proto = {
};
static int __netlink_create(struct net *net, struct socket *sock,
- struct mutex *cb_mutex, int protocol,
+ struct mutex *dump_cb_mutex, int protocol,
int kern)
{
struct sock *sk;
@@ -651,15 +651,11 @@ static int __netlink_create(struct net *net, struct socket *sock,
sock_init_data(sock, sk);
nlk = nlk_sk(sk);
- if (cb_mutex) {
- nlk->cb_mutex = cb_mutex;
- } else {
- nlk->cb_mutex = &nlk->cb_def_mutex;
- mutex_init(nlk->cb_mutex);
- lockdep_set_class_and_name(nlk->cb_mutex,
+ mutex_init(&nlk->nl_cb_mutex);
+ lockdep_set_class_and_name(&nlk->nl_cb_mutex,
nlk_cb_mutex_keys + protocol,
nlk_cb_mutex_key_strings[protocol]);
- }
+ nlk->dump_cb_mutex = dump_cb_mutex;
init_waitqueue_head(&nlk->wait);
sk->sk_destruct = netlink_sock_destruct;
@@ -1206,23 +1202,21 @@ struct sock *netlink_getsockbyfilp(struct file *filp)
struct sk_buff *netlink_alloc_large_skb(unsigned int size, int broadcast)
{
+ size_t head_size = SKB_HEAD_ALIGN(size);
struct sk_buff *skb;
void *data;
- if (size <= NLMSG_GOODSIZE || broadcast)
+ if (head_size <= PAGE_SIZE || broadcast)
return alloc_skb(size, GFP_KERNEL);
- size = SKB_DATA_ALIGN(size) +
- SKB_DATA_ALIGN(sizeof(struct skb_shared_info));
-
- data = vmalloc(size);
- if (data == NULL)
+ data = kvmalloc(head_size, GFP_KERNEL);
+ if (!data)
return NULL;
- skb = __build_skb(data, size);
- if (skb == NULL)
- vfree(data);
- else
+ skb = __build_skb(data, head_size);
+ if (!skb)
+ kvfree(data);
+ else if (is_vmalloc_addr(data))
skb->destructor = netlink_skb_destructor;
return skb;
@@ -1779,6 +1773,9 @@ static int netlink_getsockopt(struct socket *sock, int level, int optname,
netlink_unlock_table();
return err;
}
+ case NETLINK_LISTEN_ALL_NSID:
+ flag = NETLINK_F_LISTEN_ALL_NSID;
+ break;
case NETLINK_CAP_ACK:
flag = NETLINK_F_CAP_ACK;
break;
@@ -1987,7 +1984,7 @@ static int netlink_recvmsg(struct socket *sock, struct msghdr *msg, size_t len,
if (READ_ONCE(nlk->cb_running) &&
atomic_read(&sk->sk_rmem_alloc) <= sk->sk_rcvbuf / 2) {
- ret = netlink_dump(sk);
+ ret = netlink_dump(sk, false);
if (ret) {
WRITE_ONCE(sk->sk_err, -ret);
sk_error_report(sk);
@@ -2196,7 +2193,7 @@ static int netlink_dump_done(struct netlink_sock *nlk, struct sk_buff *skb,
return 0;
}
-static int netlink_dump(struct sock *sk)
+static int netlink_dump(struct sock *sk, bool lock_taken)
{
struct netlink_sock *nlk = nlk_sk(sk);
struct netlink_ext_ack extack = {};
@@ -2208,7 +2205,8 @@ static int netlink_dump(struct sock *sk)
int alloc_min_size;
int alloc_size;
- mutex_lock(nlk->cb_mutex);
+ if (!lock_taken)
+ mutex_lock(&nlk->nl_cb_mutex);
if (!nlk->cb_running) {
err = -EINVAL;
goto errout_skb;
@@ -2260,14 +2258,33 @@ static int netlink_dump(struct sock *sk)
netlink_skb_set_owner_r(skb, sk);
if (nlk->dump_done_errno > 0) {
+ struct mutex *extra_mutex = nlk->dump_cb_mutex;
+
cb->extack = &extack;
+
+ if (cb->flags & RTNL_FLAG_DUMP_UNLOCKED)
+ extra_mutex = NULL;
+ if (extra_mutex)
+ mutex_lock(extra_mutex);
nlk->dump_done_errno = cb->dump(skb, cb);
+ if (extra_mutex)
+ mutex_unlock(extra_mutex);
+
+ /* EMSGSIZE plus something already in the skb means
+ * that there's more to dump but current skb has filled up.
+ * If the callback really wants to return EMSGSIZE to user space
+ * it needs to do so again, on the next cb->dump() call,
+ * without putting data in the skb.
+ */
+ if (nlk->dump_done_errno == -EMSGSIZE && skb->len)
+ nlk->dump_done_errno = skb->len;
+
cb->extack = NULL;
}
if (nlk->dump_done_errno > 0 ||
skb_tailroom(skb) < nlmsg_total_size(sizeof(nlk->dump_done_errno))) {
- mutex_unlock(nlk->cb_mutex);
+ mutex_unlock(&nlk->nl_cb_mutex);
if (sk_filter(sk, skb))
kfree_skb(skb);
@@ -2301,13 +2318,13 @@ static int netlink_dump(struct sock *sk)
WRITE_ONCE(nlk->cb_running, false);
module = cb->module;
skb = cb->skb;
- mutex_unlock(nlk->cb_mutex);
+ mutex_unlock(&nlk->nl_cb_mutex);
module_put(module);
consume_skb(skb);
return 0;
errout_skb:
- mutex_unlock(nlk->cb_mutex);
+ mutex_unlock(&nlk->nl_cb_mutex);
kfree_skb(skb);
return err;
}
@@ -2330,7 +2347,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
}
nlk = nlk_sk(sk);
- mutex_lock(nlk->cb_mutex);
+ mutex_lock(&nlk->nl_cb_mutex);
/* A dump is in progress... */
if (nlk->cb_running) {
ret = -EBUSY;
@@ -2350,6 +2367,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
cb->data = control->data;
cb->module = control->module;
cb->min_dump_alloc = control->min_dump_alloc;
+ cb->flags = control->flags;
cb->skb = skb;
cb->strict_check = nlk_test_bit(STRICT_CHK, NETLINK_CB(skb).sk);
@@ -2365,9 +2383,7 @@ int __netlink_dump_start(struct sock *ssk, struct sk_buff *skb,
WRITE_ONCE(nlk->cb_running, true);
nlk->dump_done_errno = INT_MAX;
- mutex_unlock(nlk->cb_mutex);
-
- ret = netlink_dump(sk);
+ ret = netlink_dump(sk, true);
sock_put(sk);
@@ -2383,7 +2399,7 @@ error_put:
module_put(control->module);
error_unlock:
sock_put(sk);
- mutex_unlock(nlk->cb_mutex);
+ mutex_unlock(&nlk->nl_cb_mutex);
error_free:
kfree_skb(skb);
return ret;
generated by cgit v1.2.3 (git 2.39.0) at 2024-07-31 20:00:07 +0300