net/sched: store the last executed chain also for clsact egress

currently, only 'ingress' and 'clsact ingress' qdiscs store the tc 'chain
id' in the skb extension. However, userspace programs (like ovs) are able
to setup egress rules, and datapath gets confused in case it doesn't find
the 'chain id' for a packet that's "recirculated" by tc.
Change tcf_classify() to have the same semantic as tcf_classify_ingress()
so that a single function can be called in ingress / egress, using the tc
ingress / egress block respectively.

Suggested-by: Alaa Hleilel <alaa@nvidia.com>
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

17 files changed, 34 insertions, 43 deletions

diff --git a/net/core/dev.c b/net/core/dev.c
index dcc87fcd64babe..b51e41d0a7fe22 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -4012,7 +4012,7 @@ sch_handle_egress(struct sk_buff *skb, int *ret, struct net_device *dev)
 	qdisc_skb_cb(skb)->post_ct = false;
 	mini_qdisc_bstats_cpu_update(miniq, skb);
 
-	switch (tcf_classify(skb, miniq->filter_list, &cl_res, false)) {
+	switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) {
 	case TC_ACT_OK:
 	case TC_ACT_RECLASSIFY:
 		skb->tc_index = TC_H_MIN(cl_res.classid);
@@ -5164,8 +5164,7 @@ sch_handle_ingress(struct sk_buff *skb, struct packet_type **pt_prev, int *ret,
 	skb->tc_at_ingress = 1;
 	mini_qdisc_bstats_cpu_update(miniq, skb);
 
-	switch (tcf_classify_ingress(skb, miniq->block, miniq->filter_list,
-				     &cl_res, false)) {
+	switch (tcf_classify(skb, miniq->block, miniq->filter_list, &cl_res, false)) {
 	case TC_ACT_OK:
 	case TC_ACT_RECLASSIFY:
 		skb->tc_index = TC_H_MIN(cl_res.classid);
diff --git a/net/sched/cls_api.c b/net/sched/cls_api.c
index 1167cd0be179e2..7be5b9d2aead08 100644
--- a/net/sched/cls_api.c
+++ b/net/sched/cls_api.c
@@ -1577,21 +1577,11 @@ reset:
 #endif
 }
 
-int tcf_classify(struct sk_buff *skb, const struct tcf_proto *tp,
+int tcf_classify(struct sk_buff *skb,
+		 const struct tcf_block *block,
+		 const struct tcf_proto *tp,
 		 struct tcf_result *res, bool compat_mode)
 {
-	u32 last_executed_chain = 0;
-
-	return __tcf_classify(skb, tp, tp, res, compat_mode,
-			      &last_executed_chain);
-}
-EXPORT_SYMBOL(tcf_classify);
-
-int tcf_classify_ingress(struct sk_buff *skb,
-			 const struct tcf_block *ingress_block,
-			 const struct tcf_proto *tp,
-			 struct tcf_result *res, bool compat_mode)
-{
 #if !IS_ENABLED(CONFIG_NET_TC_SKB_EXT)
 	u32 last_executed_chain = 0;
 
@@ -1603,20 +1593,22 @@ int tcf_classify_ingress(struct sk_buff *skb,
 	struct tc_skb_ext *ext;
 	int ret;
 
-	ext = skb_ext_find(skb, TC_SKB_EXT);
+	if (block) {
+		ext = skb_ext_find(skb, TC_SKB_EXT);
 
-	if (ext && ext->chain) {
-		struct tcf_chain *fchain;
+		if (ext && ext->chain) {
+			struct tcf_chain *fchain;
 
-		fchain = tcf_chain_lookup_rcu(ingress_block, ext->chain);
-		if (!fchain)
-			return TC_ACT_SHOT;
+			fchain = tcf_chain_lookup_rcu(block, ext->chain);
+			if (!fchain)
+				return TC_ACT_SHOT;
 
-		/* Consume, so cloned/redirect skbs won't inherit ext */
-		skb_ext_del(skb, TC_SKB_EXT);
+			/* Consume, so cloned/redirect skbs won't inherit ext */
+			skb_ext_del(skb, TC_SKB_EXT);
 
-		tp = rcu_dereference_bh(fchain->filter_chain);
-		last_executed_chain = fchain->index;
+			tp = rcu_dereference_bh(fchain->filter_chain);
+			last_executed_chain = fchain->index;
+		}
 	}
 
 	ret = __tcf_classify(skb, tp, orig_tp, res, compat_mode,
@@ -1635,7 +1627,7 @@ int tcf_classify_ingress(struct sk_buff *skb,
 	return ret;
 #endif
 }
-EXPORT_SYMBOL(tcf_classify_ingress);
+EXPORT_SYMBOL(tcf_classify);
 
 struct tcf_chain_info {
 	struct tcf_proto __rcu **pprev;
@@ -3825,7 +3817,7 @@ struct sk_buff *tcf_qevent_handle(struct tcf_qevent *qe, struct Qdisc *sch, stru
 
 	fl = rcu_dereference_bh(qe->filter_chain);
 
-	switch (tcf_classify(skb, fl, &cl_res, false)) {
+	switch (tcf_classify(skb, NULL, fl, &cl_res, false)) {
 	case TC_ACT_SHOT:
 		qdisc_qstats_drop(sch);
 		__qdisc_drop(skb, to_free);
diff --git a/net/sched/sch_atm.c b/net/sched/sch_atm.c
index d0c9a57398fc26..7d8518176b45a6 100644
--- a/net/sched/sch_atm.c
+++ b/net/sched/sch_atm.c
@@ -394,7 +394,7 @@ static int atm_tc_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 		list_for_each_entry(flow, &p->flows, list) {
 			fl = rcu_dereference_bh(flow->filter_list);
 			if (fl) {
-				result = tcf_classify(skb, fl, &res, true);
+				result = tcf_classify(skb, NULL, fl, &res, true);
 				if (result < 0)
 					continue;
 				flow = (struct atm_flow_data *)res.class;
diff --git a/net/sched/sch_cake.c b/net/sched/sch_cake.c
index 951542843cab28..ecc5c4d9377921 100644
--- a/net/sched/sch_cake.c
+++ b/net/sched/sch_cake.c
@@ -1665,7 +1665,7 @@ static u32 cake_classify(struct Qdisc *sch, struct cake_tin_data **t,
 		goto hash;
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	result = tcf_classify(skb, filter, &res, false);
+	result = tcf_classify(skb, NULL, filter, &res, false);
 
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
diff --git a/net/sched/sch_cbq.c b/net/sched/sch_cbq.c
index b79a7e27bb3157..2dabaffd39d05c 100644
--- a/net/sched/sch_cbq.c
+++ b/net/sched/sch_cbq.c
@@ -228,7 +228,7 @@ cbq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 		/*
 		 * Step 2+n. Apply classifier.
 		 */
-		result = tcf_classify(skb, fl, &res, true);
+		result = tcf_classify(skb, NULL, fl, &res, true);
 		if (!fl || result < 0)
 			goto fallback;
 
diff --git a/net/sched/sch_drr.c b/net/sched/sch_drr.c
index fc1e4706959367..642cd179b7a75a 100644
--- a/net/sched/sch_drr.c
+++ b/net/sched/sch_drr.c
@@ -317,7 +317,7 @@ static struct drr_class *drr_classify(struct sk_buff *skb, struct Qdisc *sch,
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 	fl = rcu_dereference_bh(q->filter_list);
-	result = tcf_classify(skb, fl, &res, false);
+	result = tcf_classify(skb, NULL, fl, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
diff --git a/net/sched/sch_dsmark.c b/net/sched/sch_dsmark.c
index d320bcfb2da2c9..4c100d10526996 100644
--- a/net/sched/sch_dsmark.c
+++ b/net/sched/sch_dsmark.c
@@ -242,7 +242,7 @@ static int dsmark_enqueue(struct sk_buff *skb, struct Qdisc *sch,
 	else {
 		struct tcf_result res;
 		struct tcf_proto *fl = rcu_dereference_bh(p->filter_list);
-		int result = tcf_classify(skb, fl, &res, false);
+		int result = tcf_classify(skb, NULL, fl, &res, false);
 
 		pr_debug("result %d class 0x%04x\n", result, res.classid);
 
diff --git a/net/sched/sch_ets.c b/net/sched/sch_ets.c
index c1e84d1eeaba8f..925924fab1ab91 100644
--- a/net/sched/sch_ets.c
+++ b/net/sched/sch_ets.c
@@ -390,7 +390,7 @@ static struct ets_class *ets_classify(struct sk_buff *skb, struct Qdisc *sch,
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 	if (TC_H_MAJ(skb->priority) != sch->handle) {
 		fl = rcu_dereference_bh(q->filter_list);
-		err = tcf_classify(skb, fl, &res, false);
+		err = tcf_classify(skb, NULL, fl, &res, false);
 #ifdef CONFIG_NET_CLS_ACT
 		switch (err) {
 		case TC_ACT_STOLEN:
diff --git a/net/sched/sch_fq_codel.c b/net/sched/sch_fq_codel.c
index bbd5f875360062..c4afdd026f5197 100644
--- a/net/sched/sch_fq_codel.c
+++ b/net/sched/sch_fq_codel.c
@@ -91,7 +91,7 @@ static unsigned int fq_codel_classify(struct sk_buff *skb, struct Qdisc *sch,
 		return fq_codel_hash(q, skb) + 1;
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	result = tcf_classify(skb, filter, &res, false);
+	result = tcf_classify(skb, NULL, filter, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
diff --git a/net/sched/sch_fq_pie.c b/net/sched/sch_fq_pie.c
index cac684952edc55..830f3559f727ad 100644
--- a/net/sched/sch_fq_pie.c
+++ b/net/sched/sch_fq_pie.c
@@ -94,7 +94,7 @@ static unsigned int fq_pie_classify(struct sk_buff *skb, struct Qdisc *sch,
 		return fq_pie_hash(q, skb) + 1;
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	result = tcf_classify(skb, filter, &res, false);
+	result = tcf_classify(skb, NULL, filter, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
diff --git a/net/sched/sch_hfsc.c b/net/sched/sch_hfsc.c
index bf0034c66e3596..b7ac30cca035d1 100644
--- a/net/sched/sch_hfsc.c
+++ b/net/sched/sch_hfsc.c
@@ -1130,7 +1130,7 @@ hfsc_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 	head = &q->root;
 	tcf = rcu_dereference_bh(q->root.filter_list);
-	while (tcf && (result = tcf_classify(skb, tcf, &res, false)) >= 0) {
+	while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
 		case TC_ACT_QUEUED:
diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 5f7ac27a526493..81ea8332547a07 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -238,7 +238,7 @@ static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch,
 	}
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	while (tcf && (result = tcf_classify(skb, tcf, &res, false)) >= 0) {
+	while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
 		case TC_ACT_QUEUED:
diff --git a/net/sched/sch_multiq.c b/net/sched/sch_multiq.c
index 5c27b4270b9089..e282e7382117a5 100644
--- a/net/sched/sch_multiq.c
+++ b/net/sched/sch_multiq.c
@@ -36,7 +36,7 @@ multiq_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 	int err;
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	err = tcf_classify(skb, fl, &res, false);
+	err = tcf_classify(skb, NULL, fl, &res, false);
 #ifdef CONFIG_NET_CLS_ACT
 	switch (err) {
 	case TC_ACT_STOLEN:
diff --git a/net/sched/sch_prio.c b/net/sched/sch_prio.c
index 3eabb871a1d522..03fdf31ccb6aff 100644
--- a/net/sched/sch_prio.c
+++ b/net/sched/sch_prio.c
@@ -39,7 +39,7 @@ prio_classify(struct sk_buff *skb, struct Qdisc *sch, int *qerr)
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 	if (TC_H_MAJ(skb->priority) != sch->handle) {
 		fl = rcu_dereference_bh(q->filter_list);
-		err = tcf_classify(skb, fl, &res, false);
+		err = tcf_classify(skb, NULL, fl, &res, false);
 #ifdef CONFIG_NET_CLS_ACT
 		switch (err) {
 		case TC_ACT_STOLEN:
diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index b692a0de1ad5e5..58a9d42b52b8ff 100644
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -690,7 +690,7 @@ static struct qfq_class *qfq_classify(struct sk_buff *skb, struct Qdisc *sch,
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
 	fl = rcu_dereference_bh(q->filter_list);
-	result = tcf_classify(skb, fl, &res, false);
+	result = tcf_classify(skb, NULL, fl, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
diff --git a/net/sched/sch_sfb.c b/net/sched/sch_sfb.c
index dde829d4b9f834..3d061a13d7ed2b 100644
--- a/net/sched/sch_sfb.c
+++ b/net/sched/sch_sfb.c
@@ -257,7 +257,7 @@ static bool sfb_classify(struct sk_buff *skb, struct tcf_proto *fl,
 	struct tcf_result res;
 	int result;
 
-	result = tcf_classify(skb, fl, &res, false);
+	result = tcf_classify(skb, NULL, fl, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {
diff --git a/net/sched/sch_sfq.c b/net/sched/sch_sfq.c
index 066754a18569ba..f8e569f79f1367 100644
--- a/net/sched/sch_sfq.c
+++ b/net/sched/sch_sfq.c
@@ -178,7 +178,7 @@ static unsigned int sfq_classify(struct sk_buff *skb, struct Qdisc *sch,
 		return sfq_hash(q, skb) + 1;
 
 	*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
-	result = tcf_classify(skb, fl, &res, false);
+	result = tcf_classify(skb, NULL, fl, &res, false);
 	if (result >= 0) {
 #ifdef CONFIG_NET_CLS_ACT
 		switch (result) {