From: Stefan Metzmacher <metze@samba.org>
Date: Wed, 26 Oct 2022 23:25:59 +0000 (+0100)
Subject: net: also flag accepted sockets supporting msghdr originated zerocopy
X-Git-Tag: v6.0.8~38
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=cb525522fccc24baf0ca8181d54f2dd7b631bdc7;p=thirdparty%2Fkernel%2Fstable.git

net: also flag accepted sockets supporting msghdr originated zerocopy

commit 71b7786ea478f3c4611deff4d2b9676b0c17c56b upstream.

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@vger.kernel.org> # 6.0
CC: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/io-uring/20221024141503.22b4e251@kernel.org/T/#m38aa19b0b825758fb97860a38ad13122051f9dda
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/ipv4/af_inet.c b/net/ipv4/af_inet.c
index 3ca0cc4678862..7f6d7c355e38e 100644
--- a/net/ipv4/af_inet.c
+++ b/net/ipv4/af_inet.c
@@ -748,6 +748,8 @@ 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;