From ecc6ce4fdf0d62366604bc6a4cd6f50e19301a4e Mon Sep 17 00:00:00 2001 From: Eyal Birger Date: Sun, 9 Oct 2022 22:16:43 +0300 Subject: [PATCH] xfrm: fix "disable_policy" on ipv4 early demux [ Upstream commit 3a5913183aa1b14148c723bda030e6102ad73008 ] The commit in the "Fixes" tag tried to avoid a case where policy check is ignored due to dst caching in next hops. However, when the traffic is locally consumed, the dst may be cached in a local TCP or UDP socket as part of early demux. In this case the "disable_policy" flag is not checked as ip_route_input_noref() was only called before caching, and thus, packets after the initial packet in a flow will be dropped if not matching policies. Fix by checking the "disable_policy" flag also when a valid dst is already available. Link: https://bugzilla.kernel.org/show_bug.cgi?id=216557 Reported-by: Monil Patel Fixes: e6175a2ed1f1 ("xfrm: fix "disable_policy" flag use when arriving from different devices") Signed-off-by: Eyal Birger ---- v2: use dev instead of skb->dev Signed-off-by: Steffen Klassert Signed-off-by: Sasha Levin --- net/ipv4/ip_input.c | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/net/ipv4/ip_input.c b/net/ipv4/ip_input.c index 459d7e6..124bf8f 100644 --- a/net/ipv4/ip_input.c +++ b/net/ipv4/ip_input.c @@ -364,6 +364,11 @@ static int ip_rcv_finish_core(struct net *net, struct sock *sk, iph->tos, dev); if (unlikely(err)) goto drop_error; + } else { + struct in_device *in_dev = __in_dev_get_rcu(dev); + + if (in_dev && IN_DEV_ORCONF(in_dev, NOPOLICY)) + IPCB(skb)->flags |= IPSKB_NOPOLICY; } #ifdef CONFIG_IP_ROUTE_CLASSID -- 2.7.4