bpf: Call __bpf_sk_lookup()/__bpf_skc_lookup() directly via TC hookpoint

[ Upstream commit 97fbfeb86917bdbe9c41d5143e335a929147f405 ]

skb->dev always exists in the tc flow. There is no need to use
bpf_skc_lookup(), bpf_sk_lookup() from this code path.

This change facilitates fixing the tc flow to be VRF aware.

Signed-off-by: Gilad Sever <gilad9366@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Shmulik Ladkani <shmulik.ladkani@gmail.com>
Reviewed-by: Eyal Birger <eyal.birger@gmail.com>
Acked-by: Stanislav Fomichev <sdf@google.com>
Link: https://lore.kernel.org/bpf/20230621104211.301902-3-gilad9366@gmail.com
Stable-dep-of: 9a5cb79762e0 ("bpf: Fix bpf socket lookup from tc/xdp to respect socket VRF bindings")
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/net/core/filter.c b/net/core/filter.c
index e0f73ed..1b60a6c 100644 (file)
--- a/net/core/filter.c
+++ b/net/core/filter.c
@@ -6649,8 +6649,12 @@ static const struct bpf_func_proto bpf_sk_lookup_udp_proto = {
 BPF_CALL_5(bpf_tc_skc_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
 {
-       return (unsigned long)bpf_skc_lookup(skb, tuple, len, IPPROTO_TCP,
-                                            netns_id, flags);
+       struct net *caller_net = dev_net(skb->dev);
+       int ifindex = skb->dev->ifindex;
+
+       return (unsigned long)__bpf_skc_lookup(skb, tuple, len, caller_net,
+                                              ifindex, IPPROTO_TCP, netns_id,
+                                              flags);
 }
 
 static const struct bpf_func_proto bpf_tc_skc_lookup_tcp_proto = {
@@ -6668,8 +6672,12 @@ static const struct bpf_func_proto bpf_tc_skc_lookup_tcp_proto = {
 BPF_CALL_5(bpf_tc_sk_lookup_tcp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
 {
-       return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_TCP,
-                                           netns_id, flags);
+       struct net *caller_net = dev_net(skb->dev);
+       int ifindex = skb->dev->ifindex;
+
+       return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
+                                             ifindex, IPPROTO_TCP, netns_id,
+                                             flags);
 }
 
 static const struct bpf_func_proto bpf_tc_sk_lookup_tcp_proto = {
@@ -6687,8 +6695,12 @@ static const struct bpf_func_proto bpf_tc_sk_lookup_tcp_proto = {
 BPF_CALL_5(bpf_tc_sk_lookup_udp, struct sk_buff *, skb,
           struct bpf_sock_tuple *, tuple, u32, len, u64, netns_id, u64, flags)
 {
-       return (unsigned long)bpf_sk_lookup(skb, tuple, len, IPPROTO_UDP,
-                                           netns_id, flags);
+       struct net *caller_net = dev_net(skb->dev);
+       int ifindex = skb->dev->ifindex;
+
+       return (unsigned long)__bpf_sk_lookup(skb, tuple, len, caller_net,
+                                             ifindex, IPPROTO_UDP, netns_id,
+                                             flags);
 }
 
 static const struct bpf_func_proto bpf_tc_sk_lookup_udp_proto = {