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Diffstat (limited to 'net/ipv4/tcp_ao.c')
-rw-r--r--net/ipv4/tcp_ao.c22
1 files changed, 22 insertions, 0 deletions
diff --git a/net/ipv4/tcp_ao.c b/net/ipv4/tcp_ao.c
index acbeb635fe29..ffce8ca60ff2 100644
--- a/net/ipv4/tcp_ao.c
+++ b/net/ipv4/tcp_ao.c
@@ -17,6 +17,8 @@
#include <net/ipv6.h>
#include <net/icmp.h>
+DEFINE_STATIC_KEY_DEFERRED_FALSE(tcp_ao_needed, HZ);
+
int tcp_ao_calc_traffic_key(struct tcp_ao_key *mkt, u8 *key, void *ctx,
unsigned int len, struct tcp_sigpool *hp)
{
@@ -50,6 +52,9 @@ bool tcp_ao_ignore_icmp(const struct sock *sk, int family, int type, int code)
bool ignore_icmp = false;
struct tcp_ao_info *ao;
+ if (!static_branch_unlikely(&tcp_ao_needed.key))
+ return false;
+
/* RFC5925, 7.8:
* >> A TCP-AO implementation MUST default to ignore incoming ICMPv4
* messages of Type 3 (destination unreachable), Codes 2-4 (protocol
@@ -185,6 +190,9 @@ static struct tcp_ao_key *__tcp_ao_do_lookup(const struct sock *sk,
struct tcp_ao_key *key;
struct tcp_ao_info *ao;
+ if (!static_branch_unlikely(&tcp_ao_needed.key))
+ return NULL;
+
ao = rcu_dereference_check(tcp_sk(sk)->ao_info,
lockdep_sock_is_held(sk));
if (!ao)
@@ -276,6 +284,7 @@ void tcp_ao_destroy_sock(struct sock *sk, bool twsk)
}
kfree_rcu(ao, rcu);
+ static_branch_slow_dec_deferred(&tcp_ao_needed);
}
void tcp_ao_time_wait(struct tcp_timewait_sock *tcptw, struct tcp_sock *tp)
@@ -1180,6 +1189,11 @@ int tcp_ao_copy_all_matching(const struct sock *sk, struct sock *newsk,
goto free_and_exit;
}
+ if (!static_key_fast_inc_not_disabled(&tcp_ao_needed.key.key)) {
+ ret = -EUSERS;
+ goto free_and_exit;
+ }
+
key_head = rcu_dereference(hlist_first_rcu(&new_ao->head));
first_key = hlist_entry_safe(key_head, struct tcp_ao_key, node);
@@ -1607,6 +1621,10 @@ static int tcp_ao_add_cmd(struct sock *sk, unsigned short int family,
tcp_ao_link_mkt(ao_info, key);
if (first) {
+ if (!static_branch_inc(&tcp_ao_needed.key)) {
+ ret = -EUSERS;
+ goto err_free_sock;
+ }
sk_gso_disable(sk);
rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info);
}
@@ -1875,6 +1893,10 @@ static int tcp_ao_info_cmd(struct sock *sk, unsigned short int family,
if (new_rnext)
WRITE_ONCE(ao_info->rnext_key, new_rnext);
if (first) {
+ if (!static_branch_inc(&tcp_ao_needed.key)) {
+ err = -EUSERS;
+ goto out;
+ }
sk_gso_disable(sk);
rcu_assign_pointer(tcp_sk(sk)->ao_info, ao_info);
}