Without this only the client initiated tcp sockets have SOCK_SUPPORT_ZC. The listening socket on the server also has it, but the accepted connections didn't, which meant IORING_OP_SEND[MSG]_ZC will always fails with -EOPNOTSUPP. Fixes: e993ffe3da4b ("net: flag sockets supporting msghdr originated zerocopy") Cc: <stable@xxxxxxxxxxxxxxx> # 6.0 CC: Pavel Begunkov <asml.silence@xxxxxxxxx> Cc: Jakub Kicinski <kuba@xxxxxxxxxx> CC: Jens Axboe <axboe@xxxxxxxxx> Link: https://lore.kernel.org/io-uring/20221024141503.22b4e251@xxxxxxxxxx/T/#m38aa19b0b825758fb97860a38ad13122051f9dda Signed-off-by: Stefan Metzmacher <metze@xxxxxxxxx> --- net/ipv4/af_inet.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c index 3dd02396517d..4728087c42a5 100644 --- a/net/ipv4/af_inet.c +++ b/net/ipv4/af_inet.c @@ -754,6 +754,8 @@ int inet_accept(struct socket *sock, struct socket *newsock, int flags, (TCPF_ESTABLISHED | TCPF_SYN_RECV | TCPF_CLOSE_WAIT | TCPF_CLOSE))); + if (test_bit(SOCK_SUPPORT_ZC, &sock->flags)) + set_bit(SOCK_SUPPORT_ZC, &newsock->flags); sock_graft(sk2, newsock); newsock->state = SS_CONNECTED; -- 2.34.1