From: Xin Long lucien.xin@gmail.com
[ Upstream commit f799ada6bf2397c351220088b9b0980125c77280 ]
Without dropping dst, the packets sent from local mirred/redirected to ingress will may still use the old dst. ip_rcv() will drop it as the old dst is for output and its .input is dst_discard.
This patch is to fix by also dropping dst for those packets that are mirred or redirected from egress to ingress in act_mirred.
Note that we don't drop it for the direction change from ingress to egress, as on which there might be a user case attaching a metadata dst by act_tunnel_key that would be used later.
Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct") Signed-off-by: Xin Long lucien.xin@gmail.com Acked-by: Cong Wang cong.wang@bytedance.com Reviewed-by: Marcelo Ricardo Leitner marcelo.leitner@gmail.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/sched/act_mirred.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-)
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index d64b0eeccbe4d..efc963ab995a3 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -19,6 +19,7 @@ #include <linux/if_arp.h> #include <net/net_namespace.h> #include <net/netlink.h> +#include <net/dst.h> #include <net/pkt_sched.h> #include <net/pkt_cls.h> #include <linux/tc_act/tc_mirred.h> @@ -228,6 +229,7 @@ static int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a, bool want_ingress; bool is_redirect; bool expects_nh; + bool at_ingress; int m_eaction; int mac_len; bool at_nh; @@ -263,7 +265,8 @@ static int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a, * ingress - that covers the TC S/W datapath. */ is_redirect = tcf_mirred_is_act_redirect(m_eaction); - use_reinsert = skb_at_tc_ingress(skb) && is_redirect && + at_ingress = skb_at_tc_ingress(skb); + use_reinsert = at_ingress && is_redirect && tcf_mirred_can_reinsert(retval); if (!use_reinsert) { skb2 = skb_clone(skb, GFP_ATOMIC); @@ -271,10 +274,12 @@ static int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a, goto out; }
+ want_ingress = tcf_mirred_act_wants_ingress(m_eaction); + /* All mirred/redirected skbs should clear previous ct info */ nf_reset_ct(skb2); - - want_ingress = tcf_mirred_act_wants_ingress(m_eaction); + if (want_ingress && !at_ingress) /* drop dst for egress -> ingress */ + skb_dst_drop(skb2);
expects_nh = want_ingress || !m_mac_header_xmit; at_nh = skb->data == skb_network_header(skb);