netdev - [PATCH for-6.1 2/3] io_uring/net: fail zc send when unsupported by socket

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 21 Oct 2022 11:16:40 +0100
From:   Pavel Begunkov <asml.silence@...il.com>
To:     Jens Axboe <axboe@...nel.dk>, Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        "David S . Miller" <davem@...emloft.net>
Cc:     io-uring@...r.kernel.org, asml.silence@...il.com,
        netdev@...r.kernel.org, Stefan Metzmacher <metze@...ba.org>
Subject: [PATCH for-6.1 2/3] io_uring/net: fail zc send when unsupported by socket

If a protocol doesn't support zerocopy it will silently fall back to
copying. This type of behaviour has always been a source of troubles
so it's better to fail such requests instead.

Cc: <stable@...r.kernel.org> # 6.0
Signed-off-by: Pavel Begunkov <asml.silence@...il.com>
---
 io_uring/net.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/io_uring/net.c b/io_uring/net.c
index 8c7226b5bf41..26ff3675214d 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -1056,6 +1056,8 @@ int io_send_zc(struct io_kiocb *req, unsigned int issue_flags)
 	sock = sock_from_file(req->file);
 	if (unlikely(!sock))
 		return -ENOTSOCK;
+	if (!test_bit(SOCK_SUPPORT_ZC, &sock->flags))
+		return -EOPNOTSUPP;
 
 	msg.msg_name = NULL;
 	msg.msg_control = NULL;
-- 
2.38.0