It seems to be a valid use case to add xfrm state without Security Parameter Indexes (SPI) value associated: ip xfrm state add src $src dst $dst proto $proto mode $mode sel src $src dst $dst $algo
The bad thing is that it's currently impossible to get/delete the state without SPI: __xfrm_state_insert() obviously doesn't add hash for zero SPI in xfrm.state_byspi, and xfrm_user_state_lookup() will fail as xfrm_state_lookup() does lookups by hash. It also isn't possible to workaround from userspace as xfrm_id_proto_match() will be always true for ah/esp/comp protos. So, don't try looking up by hash if SPI == 0. Cc: Steffen Klassert <steffen.klass...@secunet.com> Cc: Herbert Xu <herb...@gondor.apana.org.au> Cc: "David S. Miller" <da...@davemloft.net> Cc: net...@vger.kernel.org Signed-off-by: Dmitry Safonov <d...@arista.com> --- net/xfrm/xfrm_user.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/xfrm/xfrm_user.c b/net/xfrm/xfrm_user.c index 080035f056d9..6b38503255c8 100644 --- a/net/xfrm/xfrm_user.c +++ b/net/xfrm/xfrm_user.c @@ -681,7 +681,7 @@ static struct xfrm_state *xfrm_user_state_lookup(struct net *net, int err; u32 mark = xfrm_mark_get(attrs, &m); - if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY)) { + if (xfrm_id_proto_match(p->proto, IPSEC_PROTO_ANY) && p->spi) { err = -ESRCH; x = xfrm_state_lookup(net, mark, &p->daddr, p->spi, p->proto, p->family); } else { -- 2.13.6