From mboxrd@z Thu Jan 1 00:00:00 1970 From: Dmitry Safonov Subject: [PATCH 11/18] xfrm: Add compat support for xfrm_user_expire messages Date: Thu, 26 Jul 2018 03:31:37 +0100 Message-ID: <20180726023144.31066-12-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: In-Reply-To: <20180726023144.31066-1-dima@arista.com> Sender: linux-kernel-owner@vger.kernel.org List-Id: netdev.vger.kernel.org Parse expire 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 | 95 +++++++++++++++++++++++++++++++++++----------------- 1 file changed, 65 insertions(+), 30 deletions(-) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 230462077dc9..ca1a14f45cf7 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -67,6 +67,12 @@ struct xfrm_userspi_info_packed { __u32 max; } __packed; +struct xfrm_user_expire_packed { + struct xfrm_usersa_info_packed state; + __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 @@ -2240,10 +2246,19 @@ static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh, struct net *net = sock_net(skb->sk); struct xfrm_state *x; int err; - struct xfrm_user_expire *ue = nlmsg_data(nlh); - struct xfrm_usersa_info_packed *p = (struct xfrm_usersa_info_packed *)&ue->state; + struct xfrm_user_expire_packed *ue = nlmsg_data(nlh); + struct xfrm_usersa_info_packed *p = &ue->state; struct xfrm_mark m; u32 mark = xfrm_mark_get(attrs, &m); + u8 hard; + + if (in_compat_syscall()) { + hard = ue->hard; + } else { + struct xfrm_user_expire *expire = nlmsg_data(nlh); + + hard = expire->hard; + } x = xfrm_state_lookup(net, mark, &p->id.daddr, p->id.spi, p->id.proto, p->family); @@ -2255,9 +2270,9 @@ static int xfrm_add_sa_expire(struct sk_buff *skb, struct nlmsghdr *nlh, err = -EINVAL; if (x->km.state != XFRM_STATE_VALID) goto out; - km_state_expired(x, ue->hard, nlh->nlmsg_pid); + km_state_expired(x, hard, nlh->nlmsg_pid); - if (ue->hard) { + if (hard) { __xfrm_state_delete(x); xfrm_audit_state_delete(x, 1, true); } @@ -2727,33 +2742,49 @@ static int xfrm_netlink_bind(struct net *net, unsigned long *groups) return 0; } -static inline unsigned int xfrm_expire_msgsize(void) -{ - return NLMSG_ALIGN(sizeof(struct xfrm_user_expire)) - + nla_total_size(sizeof(struct xfrm_mark)); -} - -static int build_expire(struct sk_buff *skb, struct xfrm_state *x, const struct km_event *c) +static int build_expire(struct sk_buff **skb, struct xfrm_state *x, + const struct km_event *c, bool compat) { - struct xfrm_user_expire *ue; struct nlmsghdr *nlh; + unsigned int ue_sz; int err; - nlh = nlmsg_put(skb, c->portid, 0, XFRM_MSG_EXPIRE, sizeof(*ue), 0); - if (nlh == NULL) + if (compat) + ue_sz = NLMSG_ALIGN(sizeof(struct xfrm_user_expire_packed)); + else + ue_sz = NLMSG_ALIGN(sizeof(struct xfrm_user_expire)); + + *skb = nlmsg_new(ue_sz + nla_total_size(sizeof(struct xfrm_mark)), GFP_ATOMIC); + if (*skb == NULL) + return -ENOMEM; + + nlh = nlmsg_put(*skb, c->portid, 0, XFRM_MSG_EXPIRE, ue_sz, 0); + if (nlh == NULL) { + kfree_skb(*skb); return -EMSGSIZE; + } - ue = nlmsg_data(nlh); - copy_to_user_state(x, &ue->state); - ue->hard = (c->data.hard != 0) ? 1 : 0; - /* clear the padding bytes */ - memset(&ue->hard + 1, 0, sizeof(*ue) - offsetofend(typeof(*ue), hard)); + if (compat) { + struct xfrm_user_expire_packed *ue = nlmsg_data(nlh); - err = xfrm_mark_put(skb, &x->mark); - if (err) + copy_to_user_state_compat(x, &ue->state); + ue->hard = (c->data.hard != 0) ? 1 : 0; + } else { + struct xfrm_user_expire *ue = nlmsg_data(nlh); + + copy_to_user_state(x, &ue->state); + ue->hard = (c->data.hard != 0) ? 1 : 0; + /* clear the padding bytes */ + memset(&ue->hard + 1, 0, sizeof(*ue) - offsetofend(typeof(*ue), hard)); + } + + err = xfrm_mark_put(*skb, &x->mark); + if (err) { + kfree_skb(*skb); return err; + } - nlmsg_end(skb, nlh); + nlmsg_end(*skb, nlh); return 0; } @@ -2761,17 +2792,21 @@ static int xfrm_exp_state_notify(struct xfrm_state *x, const struct km_event *c) { struct net *net = xs_net(x); struct sk_buff *skb; + int err; - skb = nlmsg_new(xfrm_expire_msgsize(), GFP_ATOMIC); - if (skb == NULL) - return -ENOMEM; + err = build_expire(&skb, x, c, false); + if (err) + return err; - if (build_expire(skb, x, c) < 0) { - kfree_skb(skb); - return -EMSGSIZE; - } + 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_expire(&skb, x, c, true); + if (err) + return err; + + return xfrm_nlmsg_multicast(net, skb, 0, XFRMNLGRP_COMPAT_EXPIRE); } static int xfrm_aevent_state_notify(struct xfrm_state *x, const struct km_event *c) -- 2.13.6