xfrm: Return error on unknown encap_type in init_state

commit bcfd09f7837f5240c30fd2f52ee7293516641faa upstream.

Currently esp will happily create an xfrm state with an unknown
encap type for IPv4, without setting the necessary state parameters.
This patch fixes it by returning -EINVAL.

There is a similar problem in IPv6 where if the mode is unknown
we will skip initialisation while returning zero.  However, this
is harmless as the mode has already been checked further up the
stack.  This patch removes this anomaly by aligning the IPv6
behaviour with IPv4 and treating unknown modes (which cannot
actually happen) as transport mode.

Fixes: 38320c70d282 ("[IPSEC]: Use crypto_aead and authenc in ESP")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c
index 360b565918c4b524d561a010ed7ec5df02312cdb..697790099a4ba19a55c71728c91b8c0a800e5b0f 100644 (file)
--- a/net/ipv4/esp4.c
+++ b/net/ipv4/esp4.c
@@ -657,6 +657,7 @@ static int esp_init_state(struct xfrm_state *x)
 
                switch (encap->encap_type) {
                default:
+                       err = -EINVAL;
                        goto error;
                case UDP_ENCAP_ESPINUDP:
                        x->props.header_len += sizeof(struct udphdr);

diff --git a/net/ipv6/esp6.c b/net/ipv6/esp6.c
index d15da1377149d3a0fdf846a7a07364e6d1251845..dda026f41af7516c5c8ce2cf130d2c951e1bdbea 100644 (file)
--- a/net/ipv6/esp6.c
+++ b/net/ipv6/esp6.c
@@ -600,13 +600,12 @@ static int esp6_init_state(struct xfrm_state *x)
                        x->props.header_len += IPV4_BEET_PHMAXLEN +
                                               (sizeof(struct ipv6hdr) - sizeof(struct iphdr));
                break;
+       default:
        case XFRM_MODE_TRANSPORT:
                break;
        case XFRM_MODE_TUNNEL:
                x->props.header_len += sizeof(struct ipv6hdr);
                break;
-       default:
-               goto error;
        }
 
        align = ALIGN(crypto_aead_blocksize(aead), 4);