tcp: Namespace-ify sysctl_tcp_challenge_ack_limit

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 6 insertions, 8 deletions

diff --git a/net/ipv4/tcp_input.c b/net/ipv4/tcp_input.c
index ce481325115f..928048a4e2c5 100644
--- a/net/ipv4/tcp_input.c
+++ b/net/ipv4/tcp_input.c
@@ -79,9 +79,6 @@
 #include <linux/unaligned/access_ok.h>
 #include <linux/static_key.h>
 
-/* rfc5961 challenge ack rate limiting */
-int sysctl_tcp_challenge_ack_limit = 1000;
-
 int sysctl_tcp_max_orphans __read_mostly = NR_FILE;
 int sysctl_tcp_min_rtt_wlen __read_mostly = 300;
 int sysctl_tcp_invalid_ratelimit __read_mostly = HZ/2;
@@ -3443,10 +3440,11 @@ static void tcp_send_challenge_ack(struct sock *sk, const struct sk_buff *skb)
         static u32 challenge_timestamp;
         static unsigned int challenge_count;
         struct tcp_sock *tp = tcp_sk(sk);
+        struct net *net = sock_net(sk);
         u32 count, now;
 
         /* First check our per-socket dupack rate limit. */
-        if (__tcp_oow_rate_limited(sock_net(sk),
+        if (__tcp_oow_rate_limited(net,
                                    LINUX_MIB_TCPACKSKIPPEDCHALLENGE,
                                    &tp->last_oow_ack_time))
                 return;
@@ -3454,16 +3452,16 @@ static void tcp_send_challenge_ack(struct sock *sk, const struct sk_buff *skb)
         /* Then check host-wide RFC 5961 rate limit. */
         now = jiffies / HZ;
         if (now != challenge_timestamp) {
-                u32 half = (sysctl_tcp_challenge_ack_limit + 1) >> 1;
+                u32 ack_limit = net->ipv4.sysctl_tcp_challenge_ack_limit;
+                u32 half = (ack_limit + 1) >> 1;
 
                 challenge_timestamp = now;
-                WRITE_ONCE(challenge_count, half +
-                           prandom_u32_max(sysctl_tcp_challenge_ack_limit));
+                WRITE_ONCE(challenge_count, half + prandom_u32_max(ack_limit));
         }
         count = READ_ONCE(challenge_count);
         if (count > 0) {
                 WRITE_ONCE(challenge_count, count - 1);
-                NET_INC_STATS(sock_net(sk), LINUX_MIB_TCPCHALLENGEACK);
+                NET_INC_STATS(net, LINUX_MIB_TCPCHALLENGEACK);
                 tcp_send_ack(sk);
         }
 }