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=-9.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,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 F4066C432C0 for ; Tue, 3 Dec 2019 22:39:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id BAA3F207DD for ; Tue, 3 Dec 2019 22:39:59 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575412799; bh=du14ndf91YLkHmlHu5bNi99zWW8kirSW/m0S6cMn+1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=KUMo8op4jXR8zx7dzKHqDpnc9ZP8Nr0gampsVn+3NQQgX1bzaiA7SPDGiBe/v/FND +pAI7pdBL2TV6AxLXLif5vRMCGqbVdJae2WX8/jGiURzkxpOxfXjSmlRiqWMwXlje4 viuMzywQfdrYB5CMorZh3JQ6EKakUHmhlsIdJ4NA= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728332AbfLCWj6 (ORCPT ); Tue, 3 Dec 2019 17:39:58 -0500 Received: from mail.kernel.org ([198.145.29.99]:51022 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727993AbfLCWj4 (ORCPT ); Tue, 3 Dec 2019 17:39:56 -0500 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 1292B20684; Tue, 3 Dec 2019 22:39:53 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1575412794; bh=du14ndf91YLkHmlHu5bNi99zWW8kirSW/m0S6cMn+1o=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FkXfHy69YwvyYm5kRSihmcox1kinXlLMMNTSxws+NGx5oJlCBdn+AHWOs89RkOYbn PKUiMtNx3/DqJlRTv2DkMjIXjHpOT0S844rezshGBuVAIQCpSUSzxktq01LoU7aC6T bRAiZFZDOzEQHy6DvOczuGToImlZSZWUJ9t/zZh8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "David S. Miller" , Jens Axboe , Sasha Levin Subject: [PATCH 5.3 002/135] net: separate out the msghdr copy from ___sys_{send,recv}msg() Date: Tue, 3 Dec 2019 23:34:02 +0100 Message-Id: <20191203213006.151586635@linuxfoundation.org> X-Mailer: git-send-email 2.24.0 In-Reply-To: <20191203213005.828543156@linuxfoundation.org> References: <20191203213005.828543156@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jens Axboe [ Upstream commit 4257c8ca13b084550574b8c9a667d9c90ff746eb ] This is in preparation for enabling the io_uring helpers for sendmsg and recvmsg to first copy the header for validation before continuing with the operation. There should be no functional changes in this patch. Acked-by: David S. Miller Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- net/socket.c | 141 ++++++++++++++++++++++++++++++++++----------------- 1 file changed, 95 insertions(+), 46 deletions(-) diff --git a/net/socket.c b/net/socket.c index 6a9ab7a8b1d2c..fbe08d7df7732 100644 --- a/net/socket.c +++ b/net/socket.c @@ -2232,15 +2232,10 @@ static int copy_msghdr_from_user(struct msghdr *kmsg, return err < 0 ? err : 0; } -static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, - struct msghdr *msg_sys, unsigned int flags, - struct used_address *used_address, - unsigned int allowed_msghdr_flags) +static int ____sys_sendmsg(struct socket *sock, struct msghdr *msg_sys, + unsigned int flags, struct used_address *used_address, + unsigned int allowed_msghdr_flags) { - struct compat_msghdr __user *msg_compat = - (struct compat_msghdr __user *)msg; - struct sockaddr_storage address; - struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; unsigned char ctl[sizeof(struct cmsghdr) + 20] __aligned(sizeof(__kernel_size_t)); /* 20 is size of ipv6_pktinfo */ @@ -2248,19 +2243,10 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, int ctl_len; ssize_t err; - msg_sys->msg_name = &address; - - if (MSG_CMSG_COMPAT & flags) - err = get_compat_msghdr(msg_sys, msg_compat, NULL, &iov); - else - err = copy_msghdr_from_user(msg_sys, msg, NULL, &iov); - if (err < 0) - return err; - err = -ENOBUFS; if (msg_sys->msg_controllen > INT_MAX) - goto out_freeiov; + goto out; flags |= (msg_sys->msg_flags & allowed_msghdr_flags); ctl_len = msg_sys->msg_controllen; if ((MSG_CMSG_COMPAT & flags) && ctl_len) { @@ -2268,7 +2254,7 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, cmsghdr_from_user_compat_to_kern(msg_sys, sock->sk, ctl, sizeof(ctl)); if (err) - goto out_freeiov; + goto out; ctl_buf = msg_sys->msg_control; ctl_len = msg_sys->msg_controllen; } else if (ctl_len) { @@ -2277,7 +2263,7 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, if (ctl_len > sizeof(ctl)) { ctl_buf = sock_kmalloc(sock->sk, ctl_len, GFP_KERNEL); if (ctl_buf == NULL) - goto out_freeiov; + goto out; } err = -EFAULT; /* @@ -2323,7 +2309,47 @@ static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, out_freectl: if (ctl_buf != ctl) sock_kfree_s(sock->sk, ctl_buf, ctl_len); -out_freeiov: +out: + return err; +} + +static int sendmsg_copy_msghdr(struct msghdr *msg, + struct user_msghdr __user *umsg, unsigned flags, + struct iovec **iov) +{ + int err; + + if (flags & MSG_CMSG_COMPAT) { + struct compat_msghdr __user *msg_compat; + + msg_compat = (struct compat_msghdr __user *) umsg; + err = get_compat_msghdr(msg, msg_compat, NULL, iov); + } else { + err = copy_msghdr_from_user(msg, umsg, NULL, iov); + } + if (err < 0) + return err; + + return 0; +} + +static int ___sys_sendmsg(struct socket *sock, struct user_msghdr __user *msg, + struct msghdr *msg_sys, unsigned int flags, + struct used_address *used_address, + unsigned int allowed_msghdr_flags) +{ + struct sockaddr_storage address; + struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; + ssize_t err; + + msg_sys->msg_name = &address; + + err = sendmsg_copy_msghdr(msg_sys, msg, flags, &iov); + if (err < 0) + return err; + + err = ____sys_sendmsg(sock, msg_sys, flags, used_address, + allowed_msghdr_flags); kfree(iov); return err; } @@ -2442,33 +2468,41 @@ SYSCALL_DEFINE4(sendmmsg, int, fd, struct mmsghdr __user *, mmsg, return __sys_sendmmsg(fd, mmsg, vlen, flags, true); } -static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg, - struct msghdr *msg_sys, unsigned int flags, int nosec) +static int recvmsg_copy_msghdr(struct msghdr *msg, + struct user_msghdr __user *umsg, unsigned flags, + struct sockaddr __user **uaddr, + struct iovec **iov) { - struct compat_msghdr __user *msg_compat = - (struct compat_msghdr __user *)msg; - struct iovec iovstack[UIO_FASTIOV]; - struct iovec *iov = iovstack; - unsigned long cmsg_ptr; - int len; ssize_t err; - /* kernel mode address */ - struct sockaddr_storage addr; - - /* user mode address pointers */ - struct sockaddr __user *uaddr; - int __user *uaddr_len = COMPAT_NAMELEN(msg); - - msg_sys->msg_name = &addr; + if (MSG_CMSG_COMPAT & flags) { + struct compat_msghdr __user *msg_compat; - if (MSG_CMSG_COMPAT & flags) - err = get_compat_msghdr(msg_sys, msg_compat, &uaddr, &iov); - else - err = copy_msghdr_from_user(msg_sys, msg, &uaddr, &iov); + msg_compat = (struct compat_msghdr __user *) umsg; + err = get_compat_msghdr(msg, msg_compat, uaddr, iov); + } else { + err = copy_msghdr_from_user(msg, umsg, uaddr, iov); + } if (err < 0) return err; + return 0; +} + +static int ____sys_recvmsg(struct socket *sock, struct msghdr *msg_sys, + struct user_msghdr __user *msg, + struct sockaddr __user *uaddr, + unsigned int flags, int nosec) +{ + struct compat_msghdr __user *msg_compat = + (struct compat_msghdr __user *) msg; + int __user *uaddr_len = COMPAT_NAMELEN(msg); + struct sockaddr_storage addr; + unsigned long cmsg_ptr; + int len; + ssize_t err; + + msg_sys->msg_name = &addr; cmsg_ptr = (unsigned long)msg_sys->msg_control; msg_sys->msg_flags = flags & (MSG_CMSG_CLOEXEC|MSG_CMSG_COMPAT); @@ -2479,7 +2513,7 @@ static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg, flags |= MSG_DONTWAIT; err = (nosec ? sock_recvmsg_nosec : sock_recvmsg)(sock, msg_sys, flags); if (err < 0) - goto out_freeiov; + goto out; len = err; if (uaddr != NULL) { @@ -2487,12 +2521,12 @@ static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg, msg_sys->msg_namelen, uaddr, uaddr_len); if (err < 0) - goto out_freeiov; + goto out; } err = __put_user((msg_sys->msg_flags & ~MSG_CMSG_COMPAT), COMPAT_FLAGS(msg)); if (err) - goto out_freeiov; + goto out; if (MSG_CMSG_COMPAT & flags) err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr, &msg_compat->msg_controllen); @@ -2500,10 +2534,25 @@ static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg, err = __put_user((unsigned long)msg_sys->msg_control - cmsg_ptr, &msg->msg_controllen); if (err) - goto out_freeiov; + goto out; err = len; +out: + return err; +} + +static int ___sys_recvmsg(struct socket *sock, struct user_msghdr __user *msg, + struct msghdr *msg_sys, unsigned int flags, int nosec) +{ + struct iovec iovstack[UIO_FASTIOV], *iov = iovstack; + /* user mode address pointers */ + struct sockaddr __user *uaddr; + ssize_t err; + + err = recvmsg_copy_msghdr(msg_sys, msg, flags, &uaddr, &iov); + if (err < 0) + return err; -out_freeiov: + err = ____sys_recvmsg(sock, msg_sys, msg, uaddr, flags, nosec); kfree(iov); return err; } -- 2.20.1