net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build

net/netfilter/nft_fwd_netdev.c: In function ‘nft_fwd_netdev_eval’:
    net/netfilter/nft_fwd_netdev.c:32:10: error: ‘struct sk_buff’ has no member named ‘tc_redirected’
      pkt->skb->tc_redirected = 1;
              ^~
    net/netfilter/nft_fwd_netdev.c:33:10: error: ‘struct sk_buff’ has no member named ‘tc_from_ingress’
      pkt->skb->tc_from_ingress = 1;
              ^~

To avoid a direct dependency with tc actions from netfilter, wrap the
redirect bits around CONFIG_NET_REDIRECT and move helpers to
include/linux/skbuff.h. Turn on this toggle from the ifb driver, the
only existing client of these bits in the tree.

This patch adds skb_set_redirected() that sets on the redirected bit
on the skbuff, it specifies if the packet was redirect from ingress
and resets the timestamp (timestamp reset was originally missing in the
netfilter bugfix).

Fixes: bcfabee1afd99484 ("netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress")
Reported-by: noreply@ellerman.id.au
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

5 files changed, 10 insertions, 10 deletions

diff --git a/net/Kconfig b/net/Kconfig
index 2eeb0e55f7c9..df8d8c9bd021 100644
--- a/net/Kconfig
+++ b/net/Kconfig
@@ -52,6 +52,9 @@ config NET_INGRESS
 config NET_EGRESS
 	bool
 
+config NET_REDIRECT
+	bool
+
 config SKB_EXTENSIONS
 	bool
 
diff --git a/net/core/dev.c b/net/core/dev.c
index 402a986659cf..500bba8874b0 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4516,7 +4516,7 @@ static u32 netif_receive_generic_xdp(struct sk_buff *skb,
 	/* Reinjected packets coming from act_mirred or similar should
 	 * not get XDP generic processing.
 	 */
-	if (skb_is_tc_redirected(skb))
+	if (skb_is_redirected(skb))
 		return XDP_PASS;
 
 	/* XDP packets must be linear and must have sufficient headroom
@@ -5063,7 +5063,7 @@ skip_taps:
 			goto out;
 	}
 #endif
-	skb_reset_tc(skb);
+	skb_reset_redirect(skb);
 skip_classify:
 	if (pfmemalloc && !skb_pfmemalloc_protocol(skb))
 		goto drop;
diff --git a/net/core/pktgen.c b/net/core/pktgen.c
index acc849df60b5..d0641bba6b81 100644
--- a/net/core/pktgen.c
+++ b/net/core/pktgen.c
@@ -3362,7 +3362,7 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev)
 			/* skb was 'freed' by stack, so clean few
 			 * bits and reuse it
 			 */
-			skb_reset_tc(skb);
+			skb_reset_redirect(skb);
 		} while (--burst > 0);
 		goto out; /* Skips xmit_mode M_START_XMIT */
 	} else if (pkt_dev->xmit_mode == M_QUEUE_XMIT) {
diff --git a/net/netfilter/nft_fwd_netdev.c b/net/netfilter/nft_fwd_netdev.c
index 74f050ba6bad..3087e23297db 100644
--- a/net/netfilter/nft_fwd_netdev.c
+++ b/net/netfilter/nft_fwd_netdev.c
@@ -28,9 +28,8 @@ static void nft_fwd_netdev_eval(const struct nft_expr *expr,
 	struct nft_fwd_netdev *priv = nft_expr_priv(expr);
 	int oif = regs->data[priv->sreg_dev];
 
-	/* These are used by ifb only. */
-	pkt->skb->tc_redirected = 1;
-	pkt->skb->tc_from_ingress = 1;
+	/* This is used by ifb only. */
+	skb_set_redirected(pkt->skb, true);
 
 	nf_fwd_netdev_egress(pkt, oif);
 	regs->verdict.code = NF_STOLEN;
diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c
index 1ad300e6dbc0..83dd82fc9f40 100644
--- a/net/sched/act_mirred.c
+++ b/net/sched/act_mirred.c
@@ -284,10 +284,8 @@ static int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a,
 
 	/* mirror is always swallowed */
 	if (is_redirect) {
-		skb2->tc_redirected = 1;
-		skb2->tc_from_ingress = skb2->tc_at_ingress;
-		if (skb2->tc_from_ingress)
-			skb2->tstamp = 0;
+		skb_set_redirected(skb2, skb2->tc_at_ingress);
+
 		/* let's the caller reinsert the packet, if possible */
 		if (use_reinsert) {
 			res->ingress = want_ingress;