From patchwork Thu May 21 00:37:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 1294864 X-Patchwork-Delegate: davem@davemloft.net Return-Path: X-Original-To: patchwork-incoming-netdev@ozlabs.org Delivered-To: patchwork-incoming-netdev@ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netdev-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=ZenIV.linux.org.uk Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 49S9j42vdKz9sRf for ; Thu, 21 May 2020 10:38:48 +1000 (AEST) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728322AbgEUAip (ORCPT ); Wed, 20 May 2020 20:38:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38542 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727954AbgEUAhY (ORCPT ); Wed, 20 May 2020 20:37:24 -0400 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E346EC061A0F; Wed, 20 May 2020 17:37:23 -0700 (PDT) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.93 #3 (Red Hat Linux)) id 1jbZD8-00Cgdg-4u; Thu, 21 May 2020 00:37:22 +0000 From: Al Viro To: netdev@vger.kernel.org Cc: davem@davemloft.net, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org Subject: [PATCH net-next 04/19] get rid of compat_mc_getsockopt() Date: Thu, 21 May 2020 01:37:06 +0100 Message-Id: <20200521003721.3023783-4-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200521003721.3023783-1-viro@ZenIV.linux.org.uk> References: <20200521003657.GE23230@ZenIV.linux.org.uk> <20200521003721.3023783-1-viro@ZenIV.linux.org.uk> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Al Viro now we can do MCAST_MSFILTER in compat ->getsockopt() without playing silly buggers with copying things back and forth. We can form a native struct group_filter (sans the variable-length tail) on stack, pass that + pointer to the tail of original request to the helper doing the bulk of the work, then do the rest of copyout - same as the native getsockopt() does. Signed-off-by: Al Viro --- include/net/compat.h | 3 -- net/compat.c | 79 ------------------------------------------------ net/ipv4/ip_sockglue.c | 44 +++++++++++++++++++++++++-- net/ipv6/ipv6_sockglue.c | 41 +++++++++++++++++++++++-- 4 files changed, 79 insertions(+), 88 deletions(-) diff --git a/include/net/compat.h b/include/net/compat.h index 69a8cd29c0ae..d714076d63d5 100644 --- a/include/net/compat.h +++ b/include/net/compat.h @@ -70,9 +70,6 @@ int cmsghdr_from_user_compat_to_kern(struct msghdr *, struct sock *, int compat_mc_setsockopt(struct sock *, int, int, char __user *, unsigned int, int (*)(struct sock *, int, int, char __user *, unsigned int)); -int compat_mc_getsockopt(struct sock *, int, int, char __user *, int __user *, - int (*)(struct sock *, int, int, char __user *, - int __user *)); struct compat_group_req { __u32 gr_interface; diff --git a/net/compat.c b/net/compat.c index 032114de4fec..7bdfda2b382a 100644 --- a/net/compat.c +++ b/net/compat.c @@ -538,85 +538,6 @@ int compat_mc_setsockopt(struct sock *sock, int level, int optname, } EXPORT_SYMBOL(compat_mc_setsockopt); -int compat_mc_getsockopt(struct sock *sock, int level, int optname, - char __user *optval, int __user *optlen, - int (*getsockopt)(struct sock *, int, int, char __user *, int __user *)) -{ - struct compat_group_filter __user *gf32 = (void __user *)optval; - struct group_filter __user *kgf; - int __user *koptlen; - u32 interface, fmode, numsrc; - int klen, ulen, err; - - if (optname != MCAST_MSFILTER) - return getsockopt(sock, level, optname, optval, optlen); - - koptlen = compat_alloc_user_space(sizeof(*koptlen)); - if (!access_ok(optlen, sizeof(*optlen)) || - __get_user(ulen, optlen)) - return -EFAULT; - - /* adjust len for pad */ - klen = ulen + sizeof(*kgf) - sizeof(*gf32); - - if (klen < GROUP_FILTER_SIZE(0)) - return -EINVAL; - - if (!access_ok(koptlen, sizeof(*koptlen)) || - __put_user(klen, koptlen)) - return -EFAULT; - - /* have to allow space for previous compat_alloc_user_space, too */ - kgf = compat_alloc_user_space(klen+sizeof(*optlen)); - - if (!access_ok(gf32, __COMPAT_GF0_SIZE) || - __get_user(interface, &gf32->gf_interface) || - __get_user(fmode, &gf32->gf_fmode) || - __get_user(numsrc, &gf32->gf_numsrc) || - __put_user(interface, &kgf->gf_interface) || - __put_user(fmode, &kgf->gf_fmode) || - __put_user(numsrc, &kgf->gf_numsrc) || - copy_in_user(&kgf->gf_group, &gf32->gf_group, sizeof(kgf->gf_group))) - return -EFAULT; - - err = getsockopt(sock, level, optname, (char __user *)kgf, koptlen); - if (err) - return err; - - if (!access_ok(koptlen, sizeof(*koptlen)) || - __get_user(klen, koptlen)) - return -EFAULT; - - ulen = klen - (sizeof(*kgf)-sizeof(*gf32)); - - if (!access_ok(optlen, sizeof(*optlen)) || - __put_user(ulen, optlen)) - return -EFAULT; - - if (!access_ok(kgf, klen) || - !access_ok(gf32, ulen) || - __get_user(interface, &kgf->gf_interface) || - __get_user(fmode, &kgf->gf_fmode) || - __get_user(numsrc, &kgf->gf_numsrc) || - __put_user(interface, &gf32->gf_interface) || - __put_user(fmode, &gf32->gf_fmode) || - __put_user(numsrc, &gf32->gf_numsrc)) - return -EFAULT; - if (numsrc) { - int copylen; - - klen -= GROUP_FILTER_SIZE(0); - copylen = numsrc * sizeof(gf32->gf_slist[0]); - if (copylen > klen) - copylen = klen; - if (copy_in_user(gf32->gf_slist, kgf->gf_slist, copylen)) - return -EFAULT; - } - return err; -} -EXPORT_SYMBOL(compat_mc_getsockopt); - - /* Argument list sizes for compat_sys_socketcall */ #define AL(x) ((x) * sizeof(u32)) static unsigned char nas[21] = { diff --git a/net/ipv4/ip_sockglue.c b/net/ipv4/ip_sockglue.c index e3703a3e7ef4..65a30e7672ff 100644 --- a/net/ipv4/ip_sockglue.c +++ b/net/ipv4/ip_sockglue.c @@ -1607,9 +1607,47 @@ int compat_ip_getsockopt(struct sock *sk, int level, int optname, { int err; - if (optname == MCAST_MSFILTER) - return compat_mc_getsockopt(sk, level, optname, optval, optlen, - ip_getsockopt); + if (optname == MCAST_MSFILTER) { + const int size0 = offsetof(struct compat_group_filter, gf_slist); + struct compat_group_filter __user *p = (void __user *)optval; + struct compat_group_filter gf32; + struct group_filter gf; + int ulen, err; + int num; + + if (level != SOL_IP) + return -EOPNOTSUPP; + + if (get_user(ulen, optlen)) + return -EFAULT; + + if (ulen < size0) + return -EINVAL; + + if (copy_from_user(&gf32, p, size0)) + return -EFAULT; + + gf.gf_interface = gf32.gf_interface; + gf.gf_fmode = gf32.gf_fmode; + num = gf.gf_numsrc = gf32.gf_numsrc; + gf.gf_group = gf32.gf_group; + + rtnl_lock(); + lock_sock(sk); + err = ip_mc_gsfget(sk, &gf, p->gf_slist); + release_sock(sk); + rtnl_unlock(); + if (err) + return err; + if (gf.gf_numsrc < num) + num = gf.gf_numsrc; + ulen = GROUP_FILTER_SIZE(num) - (sizeof(gf) - sizeof(gf32)); + if (put_user(ulen, optlen) || + put_user(gf.gf_fmode, &p->gf_fmode) || + put_user(gf.gf_numsrc, &p->gf_numsrc)) + return -EFAULT; + return 0; + } err = do_ip_getsockopt(sk, level, optname, optval, optlen, MSG_CMSG_COMPAT); diff --git a/net/ipv6/ipv6_sockglue.c b/net/ipv6/ipv6_sockglue.c index e4a62ca1a3d0..0bbafe73bdde 100644 --- a/net/ipv6/ipv6_sockglue.c +++ b/net/ipv6/ipv6_sockglue.c @@ -1446,9 +1446,44 @@ int compat_ipv6_getsockopt(struct sock *sk, int level, int optname, if (level != SOL_IPV6) return -ENOPROTOOPT; - if (optname == MCAST_MSFILTER) - return compat_mc_getsockopt(sk, level, optname, optval, optlen, - ipv6_getsockopt); + if (optname == MCAST_MSFILTER) { + const int size0 = offsetof(struct compat_group_filter, gf_slist); + struct compat_group_filter __user *p = (void __user *)optval; + struct compat_group_filter gf32; + struct group_filter gf; + int ulen, err; + int num; + + if (get_user(ulen, optlen)) + return -EFAULT; + + if (ulen < size0) + return -EINVAL; + + if (copy_from_user(&gf32, p, size0)) + return -EFAULT; + + gf.gf_interface = gf32.gf_interface; + gf.gf_fmode = gf32.gf_fmode; + num = gf.gf_numsrc = gf32.gf_numsrc; + gf.gf_group = gf32.gf_group; + + if (gf.gf_group.ss_family != AF_INET6) + return -EADDRNOTAVAIL; + lock_sock(sk); + err = ip6_mc_msfget(sk, &gf, p->gf_slist); + release_sock(sk); + if (err) + return err; + if (num > gf.gf_numsrc) + num = gf.gf_numsrc; + ulen = GROUP_FILTER_SIZE(num) - (sizeof(gf)-sizeof(gf32)); + if (put_user(ulen, optlen) || + put_user(gf.gf_fmode, &p->gf_fmode) || + put_user(gf.gf_numsrc, &p->gf_numsrc)) + return -EFAULT; + return 0; + } err = do_ipv6_getsockopt(sk, level, optname, optval, optlen, MSG_CMSG_COMPAT);