ipv6: raw: check sk->sk_rcvbuf earlier

There is no point cloning an skb and having to free the clone
if the receive queue of the raw socket is full.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://lore.kernel.org/r/20240307162943.2523817-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/net/ipv6/raw.c b/net/ipv6/raw.c
index 779274055abf99530048ad4738c2263e97c94cce..ca49e6617afaff3fe6c5f3a174bbe6d96f94ac62 100644 (file)
--- a/net/ipv6/raw.c
+++ b/net/ipv6/raw.c
@@ -160,6 +160,13 @@ static bool ipv6_raw_deliver(struct sk_buff *skb, int nexthdr)
                if (!raw_v6_match(net, sk, nexthdr, daddr, saddr,
                                  inet6_iif(skb), inet6_sdif(skb)))
                        continue;
+
+               if (atomic_read(&sk->sk_rmem_alloc) >=
+                   READ_ONCE(sk->sk_rcvbuf)) {
+                       atomic_inc(&sk->sk_drops);
+                       continue;
+               }
+
                delivered = true;
                switch (nexthdr) {
                case IPPROTO_ICMPV6: