From patchwork Mon Apr 5 08:53:08 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 415550 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-18.8 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 849C2C43470 for ; Mon, 5 Apr 2021 09:13:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 661EE61393 for ; Mon, 5 Apr 2021 09:13:15 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239442AbhDEJNT (ORCPT ); Mon, 5 Apr 2021 05:13:19 -0400 Received: from mail.kernel.org ([198.145.29.99]:60342 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239308AbhDEJNF (ORCPT ); Mon, 5 Apr 2021 05:13:05 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 17E9061002; Mon, 5 Apr 2021 09:12:57 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1617613978; bh=1GOnMOlLeJLuqLMNX4aSagmBsEVaUzYWZuK/D6aoQTc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=UOE3JM7vpqdVHcNd65xnuvgmOD5+voH02gQNHWX1BTjn0MeYMQ3Jtue0zdHVbGnhT B0K4BThHn7dIoTzbRxPASv+zmoagvESwL8XteO50jD8dwO+Bde8iQsDFSvQV8vofrS Tk5/PCjCm/kUD7Ukw5OWh7qHDU+nf1EUbndtrUk4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, netdev@vger.kernel.org, Stefan Metzmacher , Jens Axboe , Sasha Levin Subject: [PATCH 5.11 039/152] io_uring: call req_set_fail_links() on short send[msg]()/recv[msg]() with MSG_WAITALL Date: Mon, 5 Apr 2021 10:53:08 +0200 Message-Id: <20210405085035.545987518@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210405085034.233917714@linuxfoundation.org> References: <20210405085034.233917714@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Stefan Metzmacher [ Upstream commit 0031275d119efe16711cd93519b595e6f9b4b330 ] Without that it's not safe to use them in a linked combination with others. Now combinations like IORING_OP_SENDMSG followed by IORING_OP_SPLICE should be possible. We already handle short reads and writes for the following opcodes: - IORING_OP_READV - IORING_OP_READ_FIXED - IORING_OP_READ - IORING_OP_WRITEV - IORING_OP_WRITE_FIXED - IORING_OP_WRITE - IORING_OP_SPLICE - IORING_OP_TEE Now we have it for these as well: - IORING_OP_SENDMSG - IORING_OP_SEND - IORING_OP_RECVMSG - IORING_OP_RECV For IORING_OP_RECVMSG we also check for the MSG_TRUNC and MSG_CTRUNC flags in order to call req_set_fail_links(). There might be applications arround depending on the behavior that even short send[msg]()/recv[msg]() retuns continue an IOSQE_IO_LINK chain. It's very unlikely that such applications pass in MSG_WAITALL, which is only defined in 'man 2 recvmsg', but not in 'man 2 sendmsg'. It's expected that the low level sock_sendmsg() call just ignores MSG_WAITALL, as MSG_ZEROCOPY is also ignored without explicitly set SO_ZEROCOPY. We also expect the caller to know about the implicit truncation to MAX_RW_COUNT, which we don't detect. cc: netdev@vger.kernel.org Link: https://lore.kernel.org/r/c4e1a4cc0d905314f4d5dc567e65a7b09621aab3.1615908477.git.metze@samba.org Signed-off-by: Stefan Metzmacher Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- fs/io_uring.c | 24 ++++++++++++++++++++---- 1 file changed, 20 insertions(+), 4 deletions(-) diff --git a/fs/io_uring.c b/fs/io_uring.c index 26b4af9831da..2b0b9c3dda33 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4628,6 +4628,7 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, struct io_async_msghdr iomsg, *kmsg; struct socket *sock; unsigned flags; + int min_ret = 0; int ret; sock = sock_from_file(req->file); @@ -4654,6 +4655,9 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, else if (force_nonblock) flags |= MSG_DONTWAIT; + if (flags & MSG_WAITALL) + min_ret = iov_iter_count(&kmsg->msg.msg_iter); + ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags); if (force_nonblock && ret == -EAGAIN) return io_setup_async_msg(req, kmsg); @@ -4663,7 +4667,7 @@ static int io_sendmsg(struct io_kiocb *req, bool force_nonblock, if (kmsg->iov != kmsg->fast_iov) kfree(kmsg->iov); req->flags &= ~REQ_F_NEED_CLEANUP; - if (ret < 0) + if (ret < min_ret) req_set_fail_links(req); __io_req_complete(req, ret, 0, cs); return 0; @@ -4677,6 +4681,7 @@ static int io_send(struct io_kiocb *req, bool force_nonblock, struct iovec iov; struct socket *sock; unsigned flags; + int min_ret = 0; int ret; sock = sock_from_file(req->file); @@ -4698,6 +4703,9 @@ static int io_send(struct io_kiocb *req, bool force_nonblock, else if (force_nonblock) flags |= MSG_DONTWAIT; + if (flags & MSG_WAITALL) + min_ret = iov_iter_count(&msg.msg_iter); + msg.msg_flags = flags; ret = sock_sendmsg(sock, &msg); if (force_nonblock && ret == -EAGAIN) @@ -4705,7 +4713,7 @@ static int io_send(struct io_kiocb *req, bool force_nonblock, if (ret == -ERESTARTSYS) ret = -EINTR; - if (ret < 0) + if (ret < min_ret) req_set_fail_links(req); __io_req_complete(req, ret, 0, cs); return 0; @@ -4857,6 +4865,7 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, struct socket *sock; struct io_buffer *kbuf; unsigned flags; + int min_ret = 0; int ret, cflags = 0; sock = sock_from_file(req->file); @@ -4892,6 +4901,9 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, else if (force_nonblock) flags |= MSG_DONTWAIT; + if (flags & MSG_WAITALL) + min_ret = iov_iter_count(&kmsg->msg.msg_iter); + ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg, kmsg->uaddr, flags); if (force_nonblock && ret == -EAGAIN) @@ -4904,7 +4916,7 @@ static int io_recvmsg(struct io_kiocb *req, bool force_nonblock, if (kmsg->iov != kmsg->fast_iov) kfree(kmsg->iov); req->flags &= ~REQ_F_NEED_CLEANUP; - if (ret < 0) + if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC)))) req_set_fail_links(req); __io_req_complete(req, ret, cflags, cs); return 0; @@ -4920,6 +4932,7 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, struct socket *sock; struct iovec iov; unsigned flags; + int min_ret = 0; int ret, cflags = 0; sock = sock_from_file(req->file); @@ -4950,6 +4963,9 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, else if (force_nonblock) flags |= MSG_DONTWAIT; + if (flags & MSG_WAITALL) + min_ret = iov_iter_count(&msg.msg_iter); + ret = sock_recvmsg(sock, &msg, flags); if (force_nonblock && ret == -EAGAIN) return -EAGAIN; @@ -4958,7 +4974,7 @@ static int io_recv(struct io_kiocb *req, bool force_nonblock, out_free: if (req->flags & REQ_F_BUFFER_SELECTED) cflags = io_put_recv_kbuf(req); - if (ret < 0) + if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC)))) req_set_fail_links(req); __io_req_complete(req, ret, cflags, cs); return 0;