From mboxrd@z Thu Jan 1 00:00:00 1970 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=-19.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 8EE23C433E9 for ; Thu, 25 Mar 2021 11:26:40 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 635B061A45 for ; Thu, 25 Mar 2021 11:26:40 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230419AbhCYL0E (ORCPT ); Thu, 25 Mar 2021 07:26:04 -0400 Received: from mail.kernel.org ([198.145.29.99]:34300 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230368AbhCYLZ5 (ORCPT ); Thu, 25 Mar 2021 07:25:57 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id B5F4861A37; Thu, 25 Mar 2021 11:25:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1616671556; bh=9N4CGskcVvF5rLhMoXkVHr7IDC6bh+2c7ymRONRjiMI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=czXjRFGzlThfs9yamozvS6DGuKc9JJj6TtrtXJ1PSH6qNg4sSlS1v8HwA3aTth3SF fMUsqHZR8Qgh6Ei6ClYbxlrXJN1k7yQaPE7ZIdMtz0FWB9RGi56E5HABGpThAQtJmL /B6VEKS2cgMLbcOkVSR4JgwGKjCR7pqwxloHaaVpPrE2lmMgqFVvtP3deypg+FJp5E HZfvHLTpbTCck8yAf3TZl9qU15TCaCRRmVx3D9e9wf9wh1ugWg/5FWtPdCx+pFtd2K 2WPAL6oCuAZK5ZYt8O2CqJ1VV9I6rgSpBxf0zz2lINOiaRylIItIqb12aTMWe2llz0 k0r0wNeg6K12Q== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Stefan Metzmacher , netdev@vger.kernel.org, Jens Axboe , Sasha Levin , io-uring@vger.kernel.org, linux-fsdevel@vger.kernel.org Subject: [PATCH AUTOSEL 5.11 44/44] io_uring: call req_set_fail_links() on short send[msg]()/recv[msg]() with MSG_WAITALL Date: Thu, 25 Mar 2021 07:24:59 -0400 Message-Id: <20210325112459.1926846-44-sashal@kernel.org> X-Mailer: git-send-email 2.30.1 In-Reply-To: <20210325112459.1926846-1-sashal@kernel.org> References: <20210325112459.1926846-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: io-uring@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 4ac24e75ae63..c06237c87527 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -4625,6 +4625,7 @@ 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); @@ -4651,6 +4652,9 @@ 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); @@ -4660,7 +4664,7 @@ 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; @@ -4674,6 +4678,7 @@ 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); @@ -4695,6 +4700,9 @@ 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) @@ -4702,7 +4710,7 @@ 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; @@ -4854,6 +4862,7 @@ 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); @@ -4889,6 +4898,9 @@ 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) @@ -4901,7 +4913,7 @@ 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; @@ -4917,6 +4929,7 @@ 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); @@ -4947,6 +4960,9 @@ 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; @@ -4955,7 +4971,7 @@ 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; -- 2.30.1