From 88d08316dabb6462c32d0adb62c4dade71405d92 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Fri, 22 Mar 2019 16:26:19 -0700 Subject: [PATCH] xfrm: clean up xfrm protocol checks commit dbb2483b2a46fbaf833cfb5deb5ed9cace9c7399 upstream. In commit 6a53b7593233 ("xfrm: check id proto in validate_tmpl()") I introduced a check for xfrm protocol, but according to Herbert IPSEC_PROTO_ANY should only be used as a wildcard for lookup, so it should be removed from validate_tmpl(). And, IPSEC_PROTO_ANY is expected to only match 3 IPSec-specific protocols, this is why xfrm_state_flush() could still miss IPPROTO_ROUTING, which leads that those entries are left in net->xfrm.state_all before exit net. Fix this by replacing IPSEC_PROTO_ANY with zero. This patch also extracts the check from validate_tmpl() to xfrm_id_proto_valid() and uses it in parse_ipsecrequest(). With this, no other protocols should be added into xfrm. Fixes: 6a53b7593233 ("xfrm: check id proto in validate_tmpl()") Reported-by: syzbot+0bf0519d6e0de15914fe@syzkaller.appspotmail.com Cc: Steffen Klassert Cc: Herbert Xu Signed-off-by: Cong Wang Acked-by: Herbert Xu Signed-off-by: Steffen Klassert Signed-off-by: Zubin Mithra Signed-off-by: Greg Kroah-Hartman --- include/net/xfrm.h | 17 +++++++++++++++++ net/key/af_key.c | 4 +++- net/xfrm/xfrm_state.c | 2 +- net/xfrm/xfrm_user.c | 14 +------------- 4 files changed, 22 insertions(+), 15 deletions(-) diff --git a/include/net/xfrm.h b/include/net/xfrm.h index 835c30e..9e2f260 100644 --- a/include/net/xfrm.h +++ b/include/net/xfrm.h @@ -1297,6 +1297,23 @@ static inline int xfrm_state_kern(const struct xfrm_state *x) return atomic_read(&x->tunnel_users); } +static inline bool xfrm_id_proto_valid(u8 proto) +{ + switch (proto) { + case IPPROTO_AH: + case IPPROTO_ESP: + case IPPROTO_COMP: +#if IS_ENABLED(CONFIG_IPV6) + case IPPROTO_ROUTING: + case IPPROTO_DSTOPTS: +#endif + return true; + default: + return false; + } +} + +/* IPSEC_PROTO_ANY only matches 3 IPsec protocols, 0 could match all. */ static inline int xfrm_id_proto_match(u8 proto, u8 userproto) { return (!userproto || proto == userproto || diff --git a/net/key/af_key.c b/net/key/af_key.c index 36db179..d2ec620 100644 --- a/net/key/af_key.c +++ b/net/key/af_key.c @@ -1969,8 +1969,10 @@ parse_ipsecrequest(struct xfrm_policy *xp, struct sadb_x_ipsecrequest *rq) if (rq->sadb_x_ipsecrequest_mode == 0) return -EINVAL; + if (!xfrm_id_proto_valid(rq->sadb_x_ipsecrequest_proto)) + return -EINVAL; - t->id.proto = rq->sadb_x_ipsecrequest_proto; /* XXX check proto */ + t->id.proto = rq->sadb_x_ipsecrequest_proto; if ((mode = pfkey_mode_to_xfrm(rq->sadb_x_ipsecrequest_mode)) < 0) return -EINVAL; t->mode = mode; diff --git a/net/xfrm/xfrm_state.c b/net/xfrm/xfrm_state.c index 884f213..3734ad5 100644 --- a/net/xfrm/xfrm_state.c +++ b/net/xfrm/xfrm_state.c @@ -2168,7 +2168,7 @@ void xfrm_state_fini(struct net *net) unsigned int sz; flush_work(&net->xfrm.state_hash_work); - xfrm_state_flush(net, IPSEC_PROTO_ANY, false); + xfrm_state_flush(net, 0, false); flush_work(&xfrm_state_gc_work); WARN_ON(!list_empty(&net->xfrm.state_all)); diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index f3e9d50..ff641b2 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -1452,20 +1452,8 @@ static int validate_tmpl(int nr, struct xfrm_user_tmpl *ut, u16 family) return -EINVAL; } - switch (ut[i].id.proto) { - case IPPROTO_AH: - case IPPROTO_ESP: - case IPPROTO_COMP: -#if IS_ENABLED(CONFIG_IPV6) - case IPPROTO_ROUTING: - case IPPROTO_DSTOPTS: -#endif - case IPSEC_PROTO_ANY: - break; - default: + if (!xfrm_id_proto_valid(ut[i].id.proto)) return -EINVAL; - } - } return 0; -- 2.7.4