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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4F83FC0015E for ; Mon, 24 Jul 2023 17:31:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230253AbjGXRbd (ORCPT ); Mon, 24 Jul 2023 13:31:33 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38256 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230224AbjGXRbc (ORCPT ); Mon, 24 Jul 2023 13:31:32 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 05F41E78 for ; Mon, 24 Jul 2023 10:31:30 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id 41be03b00d2f7-5634dbfb8b1so2058049a12.1 for ; Mon, 24 Jul 2023 10:31:30 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1690219889; x=1690824689; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=xSgnGcg3YjnNYSyj1LYEiiwYiJRepbWFY/Wdg7LJs/Y=; b=3YEtG9bk1gL1T3vNWpdFUFjYJR41pScWP1ol0U2Wh7ZriVSchZ30bwvX9149kw3j4A GIBtYESX3ckLFfBGE48jVA2bOtYANrsjJeIpsQ1wdGtIBbozQeL62HIs7uHtPhQ/DAbP 5aQP7aTb/VM8jLrElLj3Y+ugWugqaNXgXYcMNBm1WVNMXfkfalpay+JXrPjXqzffW8Ut yh3PliqyH0esQCwTfeEKNM3RshnklWWaqcc7BnJeOESHVRDZ9erOFkZx/fbCK6U2BYR0 FscevRWHqDqDxtW0T/tuTcslEYwsuOyRjT9E8cNmswZp0pi9xb7b7u46OXNZNE6A8Pj1 WShg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1690219889; x=1690824689; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=xSgnGcg3YjnNYSyj1LYEiiwYiJRepbWFY/Wdg7LJs/Y=; b=kRVhGj+3FzeeIAmbbsVZkHcSCCSn5dQLlXVtqWnaQPbgR6kYBmis+uyfhpHgnE91Kn NhNRyQl+tUkZ4/bQUShkQLB+EkJ9ArkMuTXGG8SCWXyjV2VBUqjQQUje1V9aeHUaSCsX FVllajBXkU6Jcgs43cGnzp5uul3hLrCj0IGlca0eBwVb4td3RXQeVn22/UQHyhM5A+QA NwDAd6Xv2T2DzrRaOmVbbZJbVd+pWfSPIeRgGZbNPeVT6MfBEana76bgA80saaO9Izof h7t0enB9kdoA6klygl6X0KCkBjnZ3kRlYECeO/Rz9LnhfWkOHGxJ2etZkQAwaEt7nYTl VTHg== X-Gm-Message-State: ABy/qLY1LrKg8Tu82MH94H1cNOrbk2vVPQKZ0SWTszlU3ZbhThvpeI7X RKL/shbXXCdAaV7KQiC00ds3+po= X-Google-Smtp-Source: APBJJlEbkG2fhsk/zKDhg6WkliIQ+XgGU5IllL/bLs4sJnXLQe9xC3FBfdxqEonT/Uvq7IuAJ174ypI= X-Received: from sdf.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5935]) (user=sdf job=sendgmr) by 2002:a63:751d:0:b0:542:c9ed:b with SMTP id q29-20020a63751d000000b00542c9ed000bmr44128pgc.7.1690219889364; Mon, 24 Jul 2023 10:31:29 -0700 (PDT) Date: Mon, 24 Jul 2023 10:31:28 -0700 In-Reply-To: <20230724142237.358769-3-leitao@debian.org> Mime-Version: 1.0 References: <20230724142237.358769-1-leitao@debian.org> <20230724142237.358769-3-leitao@debian.org> Message-ID: Subject: Re: [PATCH 2/4] io_uring/cmd: Introduce SOCKET_URING_OP_GETSOCKOPT From: Stanislav Fomichev To: Breno Leitao Cc: asml.silence@gmail.com, axboe@kernel.dk, io-uring@vger.kernel.org, netdev@vger.kernel.org, davem@davemloft.net, kuba@kernel.org, edumazet@google.com, pabeni@redhat.com, linux-kernel@vger.kernel.org, leit@meta.com, bpf@vger.kernel.org Content-Type: text/plain; charset="utf-8" Precedence: bulk List-ID: X-Mailing-List: io-uring@vger.kernel.org On 07/24, Breno Leitao wrote: > Add support for getsockopt command (SOCKET_URING_OP_GETSOCKOPT), where > level is SOL_SOCKET. This is leveraging the sockptr_t infrastructure, > where a sockptr_t is either userspace or kernel space, and handled as > such. > > Function io_uring_cmd_getsockopt() is inspired by __sys_getsockopt(). We probably need to also have bpf bits in the new io_uring_cmd_getsockopt? > Differently from the getsockopt(2), the optlen field is not a userspace > pointers. In getsockopt(2), userspace provides optlen pointer, which is > overwritten by the kernel. In this implementation, userspace passes a > u32, and the new value is returned in cqe->res. I.e., optlen is not a > pointer. > > Important to say that userspace needs to keep the pointer alive until > the CQE is completed. > > Signed-off-by: Breno Leitao > --- > include/uapi/linux/io_uring.h | 7 ++++++ > io_uring/uring_cmd.c | 43 +++++++++++++++++++++++++++++++++++ > 2 files changed, 50 insertions(+) > > diff --git a/include/uapi/linux/io_uring.h b/include/uapi/linux/io_uring.h > index 9fc7195f25df..8152151080db 100644 > --- a/include/uapi/linux/io_uring.h > +++ b/include/uapi/linux/io_uring.h > @@ -43,6 +43,10 @@ struct io_uring_sqe { > union { > __u64 addr; /* pointer to buffer or iovecs */ > __u64 splice_off_in; > + struct { > + __u32 level; > + __u32 optname; > + }; > }; > __u32 len; /* buffer size or number of iovecs */ > union { > @@ -79,6 +83,7 @@ struct io_uring_sqe { > union { > __s32 splice_fd_in; > __u32 file_index; > + __u32 optlen; > struct { > __u16 addr_len; > __u16 __pad3[1]; > @@ -89,6 +94,7 @@ struct io_uring_sqe { > __u64 addr3; > __u64 __pad2[1]; > }; > + __u64 optval; > /* > * If the ring is initialized with IORING_SETUP_SQE128, then > * this field is used for 80 bytes of arbitrary command data > @@ -729,6 +735,7 @@ struct io_uring_recvmsg_out { > enum { > SOCKET_URING_OP_SIOCINQ = 0, > SOCKET_URING_OP_SIOCOUTQ, > + SOCKET_URING_OP_GETSOCKOPT, > }; > > #ifdef __cplusplus > diff --git a/io_uring/uring_cmd.c b/io_uring/uring_cmd.c > index 8e7a03c1b20e..16c857cbf3b0 100644 > --- a/io_uring/uring_cmd.c > +++ b/io_uring/uring_cmd.c > @@ -166,6 +166,47 @@ int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw, > } > EXPORT_SYMBOL_GPL(io_uring_cmd_import_fixed); > > +static inline int io_uring_cmd_getsockopt(struct socket *sock, > + struct io_uring_cmd *cmd) > +{ > + void __user *optval = u64_to_user_ptr(READ_ONCE(cmd->sqe->optval)); > + int optname = READ_ONCE(cmd->sqe->optname); > + int optlen = READ_ONCE(cmd->sqe->optlen); > + int level = READ_ONCE(cmd->sqe->level); > + void *koptval; > + int err; > + > + err = security_socket_getsockopt(sock, level, optname); > + if (err) > + return err; > + > + koptval = kmalloc(optlen, GFP_KERNEL); > + if (!koptval) > + return -ENOMEM; > + > + err = copy_from_user(koptval, optval, optlen); > + if (err) > + goto fail; > + > + err = -EOPNOTSUPP; > + if (level == SOL_SOCKET) { > + err = sk_getsockopt(sock->sk, level, optname, > + KERNEL_SOCKPTR(koptval), > + KERNEL_SOCKPTR(&optlen)); > + if (err) > + goto fail; > + } > + > + err = copy_to_user(optval, koptval, optlen); > + > +fail: > + kfree(koptval); > + if (err) > + return err; > + else > + return optlen; > +} > + > int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags) > { > struct socket *sock = cmd->file->private_data; > @@ -187,6 +228,8 @@ int io_uring_cmd_sock(struct io_uring_cmd *cmd, unsigned int issue_flags) > if (ret) > return ret; > return arg; > + case SOCKET_URING_OP_GETSOCKOPT: > + return io_uring_cmd_getsockopt(sock, cmd); > default: > return -EOPNOTSUPP; > } > -- > 2.34.1 >