From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Safonov Subject: [PATCH 14/18] xfrm: Add compat support for xfrm_user_polexpire messages Date: Thu, 26 Jul 2018 03:31:40 +0100 Message-ID: <20180726023144.31066-15-dima@arista.com> References: <20180726023144.31066-1-dima@arista.com> Cc: Dmitry Safonov , "David S. Miller" , Herbert Xu , Steffen Klassert , Dmitry Safonov <0x7f454c46@gmail.com>, netdev@vger.kernel.org To: linux-kernel@vger.kernel.org Return-path: Received: from mail-ed1-f66.google.com ([209.85.208.66]:41368 "EHLO mail-ed1-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729038AbeGZDqg (ORCPT ); Wed, 25 Jul 2018 23:46:36 -0400 Received: by mail-ed1-f66.google.com with SMTP id s24-v6so330196edr.8 for ; Wed, 25 Jul 2018 19:32:03 -0700 (PDT) In-Reply-To: <20180726023144.31066-1-dima@arista.com> Sender: netdev-owner@vger.kernel.org List-ID: Parse polexpire messages sent by userspace according to in_compat_syscall(). Applications that used native bind() syscall are in XFRMNLGRP_EXPIRE, so send there xfrm_usersa_info messages (with 64-bit ABI). Compatible applications are added to kernel-hidden XFRMNLGRP_COMPAT_EXPIRE group, so send there xfrm_usersa_info messages_packed (with 32-bit ABI) Cc: "David S. Miller" Cc: Herbert Xu Cc: Steffen Klassert Cc: netdev@vger.kernel.org Signed-off-by: Dmitry Safonov --- net/xfrm/xfrm_user.c | 89 +++++++++++++++++++++++++++++++++++----------------- 1 file changed, 61 insertions(+), 28 deletions(-) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 89f891a0a9a4..2fe6174b8a18 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -84,6 +84,12 @@ struct xfrm_user_acquire_packed { __u32 seq; } __packed; +struct xfrm_user_polexpire_packed { + struct xfrm_userpolicy_info_packed pol; + __u8 hard; + __u8 __pad[3]; +} __packed; + /* In-kernel, non-uapi compat groups. * As compat/native messages differ, send notifications according * to .bind() caller's ABI. There are *_COMPAT hidden from userspace @@ -2225,7 +2231,15 @@ static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh, int err = -ENOENT; struct xfrm_mark m; u32 mark = xfrm_mark_get(attrs, &m); + u8 hard; + if (in_compat_syscall()) { + struct xfrm_user_polexpire_packed *_up = nlmsg_data(nlh); + + hard = _up->hard; + } else { + hard = up->hard; + } err = copy_from_user_policy_type(&type, attrs); if (err) return err; @@ -2263,11 +2277,11 @@ static int xfrm_add_pol_expire(struct sk_buff *skb, struct nlmsghdr *nlh, goto out; err = 0; - if (up->hard) { + if (hard) { xfrm_policy_delete(xp, p->dir); xfrm_audit_policy_delete(xp, 1, true); } - km_policy_expired(xp, p->dir, up->hard, nlh->nlmsg_pid); + km_policy_expired(xp, p->dir, hard, nlh->nlmsg_pid); out: xfrm_pol_put(xp); @@ -3192,43 +3206,59 @@ static struct xfrm_policy *xfrm_compile_policy(struct sock *sk, int opt, return xp; } -static inline unsigned int xfrm_polexpire_msgsize(struct xfrm_policy *xp) +static int build_polexpire(struct sk_buff **skb, struct xfrm_policy *xp, + int dir, const struct km_event *c, bool compat) { - return NLMSG_ALIGN(sizeof(struct xfrm_user_polexpire)) + struct xfrm_user_polexpire_packed *_upe; + struct xfrm_user_polexpire *upe; + unsigned int upe_size, polexpire_msgsize; + int hard = c->data.hard; + struct nlmsghdr *nlh; + int err; + + if (compat) + upe_size = NLMSG_ALIGN(sizeof(struct xfrm_user_polexpire_packed)); + else + upe_size = NLMSG_ALIGN(sizeof(struct xfrm_user_polexpire)); + polexpire_msgsize = upe_size + nla_total_size(sizeof(struct xfrm_user_tmpl) * xp->xfrm_nr) + nla_total_size(xfrm_user_sec_ctx_size(xp->security)) + nla_total_size(sizeof(struct xfrm_mark)) + userpolicy_type_attrsize(); -} -static int build_polexpire(struct sk_buff *skb, struct xfrm_policy *xp, - int dir, const struct km_event *c) -{ - struct xfrm_user_polexpire *upe; - int hard = c->data.hard; - struct nlmsghdr *nlh; - int err; + *skb = nlmsg_new(polexpire_msgsize, GFP_ATOMIC); + if (*skb == NULL) + return -ENOMEM; - nlh = nlmsg_put(skb, c->portid, 0, XFRM_MSG_POLEXPIRE, sizeof(*upe), 0); + nlh = nlmsg_put(*skb, c->portid, 0, XFRM_MSG_POLEXPIRE, upe_size, 0); if (nlh == NULL) return -EMSGSIZE; + _upe = nlmsg_data(nlh); upe = nlmsg_data(nlh); - copy_to_user_policy(xp, &upe->pol, dir); - err = copy_to_user_tmpl(xp, skb); + if (compat) + copy_to_user_policy_compat(xp, &_upe->pol, dir); + else + copy_to_user_policy(xp, &upe->pol, dir); + + err = copy_to_user_tmpl(xp, *skb); if (!err) - err = copy_to_user_sec_ctx(xp, skb); + err = copy_to_user_sec_ctx(xp, *skb); if (!err) - err = copy_to_user_policy_type(xp->type, skb); + err = copy_to_user_policy_type(xp->type, *skb); if (!err) - err = xfrm_mark_put(skb, &xp->mark); + err = xfrm_mark_put(*skb, &xp->mark); if (err) { - nlmsg_cancel(skb, nlh); + nlmsg_cancel(*skb, nlh); return err; } - upe->hard = !!hard; - nlmsg_end(skb, nlh); + if (compat) + _upe->hard = !!hard; + else + upe->hard = !!hard; + + nlmsg_end(*skb, nlh); return 0; } @@ -3238,14 +3268,17 @@ static int xfrm_exp_policy_notify(struct xfrm_policy *xp, int dir, const struct struct sk_buff *skb; int err; - skb = nlmsg_new(xfrm_polexpire_msgsize(xp), GFP_ATOMIC); - if (skb == NULL) - return -ENOMEM; - - err = build_polexpire(skb, xp, dir, c); - BUG_ON(err < 0); + err = build_polexpire(&skb, xp, dir, c, false); + if (err) + return err; + err = xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_EXPIRE); + if ((err && err != -ESRCH) || !IS_ENABLED(CONFIG_COMPAT)) + return err; - return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_EXPIRE); + err = build_polexpire(&skb, xp, dir, c, true); + if (err) + return err; + return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_COMPAT_EXPIRE); } static int __xfrm_notify_policy(struct xfrm_policy *xp, int dir, -- 2.13.6