Merge branch 'ocelot-vcap-fixes'

Vladimir Oltean says:

====================
Ocelot VCAP fixes

Changes in v2:
fix the NPDs and UAFs caused by filter->trap_list in a more robust way
that actually does not introduce bugs of its own (1/5)

This series fixes issues found while running
tools/testing/selftests/net/forwarding/tc_actions.sh on the ocelot
switch:

- NULL pointer dereference when failing to offload a filter
- NULL pointer dereference after deleting a trap
- filters still having effect after being deleted
- dropped packets still being seen by software
- statistics counters showing double the amount of hits
- statistics counters showing inexistent hits
- invalid configurations not rejected
====================

Link: https://lore.kernel.org/r/20220504235503.4161890-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

5 files changed, 22 insertions, 16 deletions

diff --git a/drivers/net/dsa/ocelot/felix.c b/drivers/net/dsa/ocelot/felix.c
index 9e28219b223d..faccfb3f0158 100644
--- a/drivers/net/dsa/ocelot/felix.c
+++ b/drivers/net/dsa/ocelot/felix.c
@@ -403,6 +403,7 @@ static int felix_update_trapping_destinations(struct dsa_switch *ds,
 {
 	struct ocelot *ocelot = ds->priv;
 	struct felix *felix = ocelot_to_felix(ocelot);
+	struct ocelot_vcap_block *block_vcap_is2;
 	struct ocelot_vcap_filter *trap;
 	enum ocelot_mask_mode mask_mode;
 	unsigned long port_mask;
@@ -422,9 +423,13 @@ static int felix_update_trapping_destinations(struct dsa_switch *ds,
 	/* We are sure that "cpu" was found, otherwise
 	 * dsa_tree_setup_default_cpu() would have failed earlier.
 	 */
+	block_vcap_is2 = &ocelot->block[VCAP_IS2];
 
 	/* Make sure all traps are set up for that destination */
-	list_for_each_entry(trap, &ocelot->traps, trap_list) {
+	list_for_each_entry(trap, &block_vcap_is2->rules, list) {
+		if (!trap->is_trap)
+			continue;
+
 		/* Figure out the current trapping destination */
 		if (using_tag_8021q) {
 			/* Redirect to the tag_8021q CPU port. If timestamps
diff --git a/drivers/net/ethernet/mscc/ocelot.c b/drivers/net/ethernet/mscc/ocelot.c
index ca71b62a44dc..20ceac81a2c2 100644
--- a/drivers/net/ethernet/mscc/ocelot.c
+++ b/drivers/net/ethernet/mscc/ocelot.c
@@ -1622,7 +1622,7 @@ int ocelot_trap_add(struct ocelot *ocelot, int port,
 		trap->action.mask_mode = OCELOT_MASK_MODE_PERMIT_DENY;
 		trap->action.port_mask = 0;
 		trap->take_ts = take_ts;
-		list_add_tail(&trap->trap_list, &ocelot->traps);
+		trap->is_trap = true;
 		new = true;
 	}
 
@@ -1634,10 +1634,8 @@ int ocelot_trap_add(struct ocelot *ocelot, int port,
 		err = ocelot_vcap_filter_replace(ocelot, trap);
 	if (err) {
 		trap->ingress_port_mask &= ~BIT(port);
-		if (!trap->ingress_port_mask) {
-			list_del(&trap->trap_list);
+		if (!trap->ingress_port_mask)
 			kfree(trap);
-		}
 		return err;
 	}
 
@@ -1657,11 +1655,8 @@ int ocelot_trap_del(struct ocelot *ocelot, int port, unsigned long cookie)
 		return 0;
 
 	trap->ingress_port_mask &= ~BIT(port);
-	if (!trap->ingress_port_mask) {
-		list_del(&trap->trap_list);
-
+	if (!trap->ingress_port_mask)
 		return ocelot_vcap_filter_del(ocelot, trap);
-	}
 
 	return ocelot_vcap_filter_replace(ocelot, trap);
 }
diff --git a/drivers/net/ethernet/mscc/ocelot_flower.c b/drivers/net/ethernet/mscc/ocelot_flower.c
index 03b5e59d033e..51cf241ff7d0 100644
--- a/drivers/net/ethernet/mscc/ocelot_flower.c
+++ b/drivers/net/ethernet/mscc/ocelot_flower.c
@@ -280,9 +280,10 @@ static int ocelot_flower_parse_action(struct ocelot *ocelot, int port,
 			filter->type = OCELOT_VCAP_FILTER_OFFLOAD;
 			break;
 		case FLOW_ACTION_TRAP:
-			if (filter->block_id != VCAP_IS2) {
+			if (filter->block_id != VCAP_IS2 ||
+			    filter->lookup != 0) {
 				NL_SET_ERR_MSG_MOD(extack,
-						   "Trap action can only be offloaded to VCAP IS2");
+						   "Trap action can only be offloaded to VCAP IS2 lookup 0");
 				return -EOPNOTSUPP;
 			}
 			if (filter->goto_target != -1) {
@@ -295,7 +296,7 @@ static int ocelot_flower_parse_action(struct ocelot *ocelot, int port,
 			filter->action.cpu_copy_ena = true;
 			filter->action.cpu_qu_num = 0;
 			filter->type = OCELOT_VCAP_FILTER_OFFLOAD;
-			list_add_tail(&filter->trap_list, &ocelot->traps);
+			filter->is_trap = true;
 			break;
 		case FLOW_ACTION_POLICE:
 			if (filter->block_id == PSFP_BLOCK_ID) {
@@ -878,8 +879,6 @@ int ocelot_cls_flower_replace(struct ocelot *ocelot, int port,
 
 	ret = ocelot_flower_parse(ocelot, port, ingress, f, filter);
 	if (ret) {
-		if (!list_empty(&filter->trap_list))
-			list_del(&filter->trap_list);
 		kfree(filter);
 		return ret;
 	}
diff --git a/drivers/net/ethernet/mscc/ocelot_vcap.c b/drivers/net/ethernet/mscc/ocelot_vcap.c
index c8701ac955a8..eeb4cc07dd16 100644
--- a/drivers/net/ethernet/mscc/ocelot_vcap.c
+++ b/drivers/net/ethernet/mscc/ocelot_vcap.c
@@ -374,7 +374,6 @@ static void is2_entry_set(struct ocelot *ocelot, int ix,
 			 OCELOT_VCAP_BIT_0);
 	vcap_key_set(vcap, &data, VCAP_IS2_HK_IGR_PORT_MASK, 0,
 		     ~filter->ingress_port_mask);
-	vcap_key_bit_set(vcap, &data, VCAP_IS2_HK_FIRST, OCELOT_VCAP_BIT_ANY);
 	vcap_key_bit_set(vcap, &data, VCAP_IS2_HK_HOST_MATCH,
 			 OCELOT_VCAP_BIT_ANY);
 	vcap_key_bit_set(vcap, &data, VCAP_IS2_HK_L2_MC, filter->dmac_mc);
@@ -1217,6 +1216,8 @@ int ocelot_vcap_filter_add(struct ocelot *ocelot,
 		struct ocelot_vcap_filter *tmp;
 
 		tmp = ocelot_vcap_block_find_filter_by_index(block, i);
+		/* Read back the filter's counters before moving it */
+		vcap_entry_get(ocelot, i - 1, tmp);
 		vcap_entry_set(ocelot, i, tmp);
 	}
 
@@ -1250,7 +1251,11 @@ int ocelot_vcap_filter_del(struct ocelot *ocelot,
 	struct ocelot_vcap_filter del_filter;
 	int i, index;
 
+	/* Need to inherit the block_id so that vcap_entry_set()
+	 * does not get confused and knows where to install it.
+	 */
 	memset(&del_filter, 0, sizeof(del_filter));
+	del_filter.block_id = filter->block_id;
 
 	/* Gets index of the filter */
 	index = ocelot_vcap_block_get_filter_index(block, filter);
@@ -1265,6 +1270,8 @@ int ocelot_vcap_filter_del(struct ocelot *ocelot,
 		struct ocelot_vcap_filter *tmp;
 
 		tmp = ocelot_vcap_block_find_filter_by_index(block, i);
+		/* Read back the filter's counters before moving it */
+		vcap_entry_get(ocelot, i + 1, tmp);
 		vcap_entry_set(ocelot, i, tmp);
 	}
 
diff --git a/include/soc/mscc/ocelot_vcap.h b/include/soc/mscc/ocelot_vcap.h
index 7b2bf9b1fe69..de26c992f821 100644
--- a/include/soc/mscc/ocelot_vcap.h
+++ b/include/soc/mscc/ocelot_vcap.h
@@ -681,7 +681,6 @@ struct ocelot_vcap_id {
 
 struct ocelot_vcap_filter {
 	struct list_head list;
-	struct list_head trap_list;
 
 	enum ocelot_vcap_filter_type type;
 	int block_id;
@@ -695,6 +694,7 @@ struct ocelot_vcap_filter {
 	struct ocelot_vcap_stats stats;
 	/* For VCAP IS1 and IS2 */
 	bool take_ts;
+	bool is_trap;
 	unsigned long ingress_port_mask;
 	/* For VCAP ES0 */
 	struct ocelot_vcap_port ingress_port;