PF_VSOCK supports MSG_ZEROCOPY transmission, so SO_ZEROCOPY could
be enabled. PF_VSOCK implementation is a little bit special comparing to
PF_INET - MSG_ZEROCOPY support depends on transport layer of PF_VSOCK,
but here we can't "ask" its transport, so setting of this option is
always allowed, but if some transport doesn't support zerocopy tx, send
callback of PF_VSOCK will return -EOPNOTSUPP.

Signed-off-by: Arseniy Krasnov <redacted>
---
 net/core/sock.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/net/core/sock.c b/net/core/sock.c
index 5440e67bcfe3..d558e541e6d7 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c

@@ -1452,9 +1452,11 @@ int sk_setsockopt(struct sock *sk, int level, int optname,
 			      (sk->sk_type == SOCK_DGRAM &&
 			       sk->sk_protocol == IPPROTO_UDP)))
 				ret = -EOPNOTSUPP;
-		} else if (sk->sk_family != PF_RDS) {
+		} else if (sk->sk_family != PF_RDS &&
+			   sk->sk_family != PF_VSOCK) {
 			ret = -EOPNOTSUPP;
 		}
+
 		if (!ret) {
 			if (val < 0 || val > 1)
 				ret = -EINVAL;

-- 
2.25.1