From edf81438799ccead7122948446d7e44b083e788d Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Fri, 21 Oct 2022 11:16:40 +0100 Subject: [PATCH] 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: # 6.0 Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/2db3c7f16bb6efab4b04569cd16e6242b40c5cb3.1666346426.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- 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;