4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Richard Haines <richard_c_haines@xxxxxxxxxxxxxx> [ Upstream commit 213d7f94775322ba44e0bbb55ec6946e9de88cea ] When resolving a fallback label, check the sk_buff version as it is possible (e.g. SCTP) to have family = PF_INET6 while receiving ip_hdr(skb)->version = 4. Signed-off-by: Richard Haines <richard_c_haines@xxxxxxxxxxxxxx> Acked-by: Paul Moore <paul@xxxxxxxxxxxxxx> Signed-off-by: Paul Moore <paul@xxxxxxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netlabel/netlabel_unlabeled.c | 10 ++++++++++ 1 file changed, 10 insertions(+) --- a/net/netlabel/netlabel_unlabeled.c +++ b/net/netlabel/netlabel_unlabeled.c @@ -1469,6 +1469,16 @@ int netlbl_unlabel_getattr(const struct iface = rcu_dereference(netlbl_unlhsh_def); if (iface == NULL || !iface->valid) goto unlabel_getattr_nolabel; + +#if IS_ENABLED(CONFIG_IPV6) + /* When resolving a fallback label, check the sk_buff version as + * it is possible (e.g. SCTP) to have family = PF_INET6 while + * receiving ip_hdr(skb)->version = 4. + */ + if (family == PF_INET6 && ip_hdr(skb)->version == 4) + family = PF_INET; +#endif /* IPv6 */ + switch (family) { case PF_INET: { struct iphdr *hdr4;