Bluetooth: Set filter policy for LE connection

[platform/kernel/linux-starfive.git] / net / unix / unix_bpf.c

diff --git a/net/unix/unix_bpf.c b/net/unix/unix_bpf.c
index 2f9d827..bd84785 100644 (file)
--- a/net/unix/unix_bpf.c
+++ b/net/unix/unix_bpf.c
@@ -159,12 +159,32 @@ int unix_dgram_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool re
 
 int unix_stream_bpf_update_proto(struct sock *sk, struct sk_psock *psock, bool restore)
 {
+       struct sock *sk_pair;
+
+       /* Restore does not decrement the sk_pair reference yet because we must
+        * keep the a reference to the socket until after an RCU grace period
+        * and any pending sends have completed.
+        */
        if (restore) {
                sk->sk_write_space = psock->saved_write_space;
                sock_replace_proto(sk, psock->sk_proto);
                return 0;
        }
 
+       /* psock_update_sk_prot can be called multiple times if psock is
+        * added to multiple maps and/or slots in the same map. There is
+        * also an edge case where replacing a psock with itself can trigger
+        * an extra psock_update_sk_prot during the insert process. So it
+        * must be safe to do multiple calls. Here we need to ensure we don't
+        * increment the refcnt through sock_hold many times. There will only
+        * be a single matching destroy operation.
+        */
+       if (!psock->sk_pair) {
+               sk_pair = unix_peer(sk);
+               sock_hold(sk_pair);
+               psock->sk_pair = sk_pair;
+       }
+
        unix_stream_bpf_check_needs_rebuild(psock->sk_proto);
        sock_replace_proto(sk, &unix_stream_bpf_prot);
        return 0;