[PATCH net 1/2] mlxsw: spectrum_flower: Fix port range register leak in tmplt_create()

[Petr Machata <petrm@nvidia.com>]

mlxsw_sp_flower_tmplt_create() parses a flow_cls_offload template
into a stack-local struct mlxsw_sp_acl_rule_info purely to compute
rulei.values.elusage. Parsing can acquire port range registers via
mlxsw_sp_flower_parse_ports_range(), but since this rulei never goes
through mlxsw_sp_acl_rulei_destroy(), those registers were never
released, including through chain template deletion.

Factor out of mlxsw_sp_acl_rulei_destroy() the code to actually
release the necessary resources and call from
mlxsw_sp_flower_tmplt_create() to plug the leak.

The issue was found during a review of Wentao Liang's patch referenced
below.

Fixes: fe22f7410527 ("mlxsw: spectrum_flower: Add ability to match on port ranges")
Reported-by: Wentao Liang <vulab@iscas.ac.cn>
Closes: https://lore.kernel.org/netdev/20260917113236.2149095-1-vulab@iscas.ac.cn/
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Signed-off-by: Petr Machata <petrm@nvidia.com>
---
 drivers/net/ethernet/mellanox/mlxsw/spectrum.h        |  2 ++
 drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c    | 10 ++++++++--
 drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c |  9 +++++++--
 3 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
index b03ff9e044f9..10af08ce72ef 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum.h
@@ -989,6 +989,8 @@ void mlxsw_sp_acl_ruleset_prio_get(struct mlxsw_sp_acl_ruleset *ruleset,
 struct mlxsw_sp_acl_rule_info *
 mlxsw_sp_acl_rulei_create(struct mlxsw_sp_acl *acl,
 			  struct mlxsw_afa_block *afa_block);
+void mlxsw_sp_acl_rulei_free(struct mlxsw_sp *mlxsw_sp,
+			     const struct mlxsw_sp_acl_rule_info *rulei);
 void mlxsw_sp_acl_rulei_destroy(struct mlxsw_sp *mlxsw_sp,
 				struct mlxsw_sp_acl_rule_info *rulei);
 int mlxsw_sp_acl_rulei_commit(struct mlxsw_sp_acl_rule_info *rulei);
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
index cb232accb296..f7be4f3a1518 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_acl.c
@@ -340,8 +340,8 @@ mlxsw_sp_acl_rulei_create(struct mlxsw_sp_acl *acl,
 	return ERR_PTR(err);
 }
 
-void mlxsw_sp_acl_rulei_destroy(struct mlxsw_sp *mlxsw_sp,
-				struct mlxsw_sp_acl_rule_info *rulei)
+void mlxsw_sp_acl_rulei_free(struct mlxsw_sp *mlxsw_sp,
+			     const struct mlxsw_sp_acl_rule_info *rulei)
 {
 	if (rulei->action_created)
 		mlxsw_afa_block_destroy(rulei->act_block);
@@ -351,6 +351,12 @@ void mlxsw_sp_acl_rulei_destroy(struct mlxsw_sp *mlxsw_sp,
 	if (rulei->dst_port_range_reg_valid)
 		mlxsw_sp_port_range_reg_put(mlxsw_sp,
 					    rulei->dst_port_range_reg_index);
+}
+
+void mlxsw_sp_acl_rulei_destroy(struct mlxsw_sp *mlxsw_sp,
+				struct mlxsw_sp_acl_rule_info *rulei)
+{
+	mlxsw_sp_acl_rulei_free(mlxsw_sp, rulei);
 	kfree(rulei);
 }
 
diff --git a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
index 353fd9ca89a6..5e4632cb792d 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
+++ b/drivers/net/ethernet/mellanox/mlxsw/spectrum_flower.c
@@ -862,14 +862,19 @@ int mlxsw_sp_flower_tmplt_create(struct mlxsw_sp *mlxsw_sp,
 	memset(&rulei, 0, sizeof(rulei));
 	err = mlxsw_sp_flower_parse(mlxsw_sp, block, &rulei, f);
 	if (err)
-		return err;
+		goto out;
+
 	ruleset = mlxsw_sp_acl_ruleset_get(mlxsw_sp, block,
 					   f->common.chain_index,
 					   MLXSW_SP_ACL_PROFILE_FLOWER,
 					   &rulei.values.elusage);
+	err = PTR_ERR_OR_ZERO(ruleset);
+
+out:
+	mlxsw_sp_acl_rulei_free(mlxsw_sp, &rulei);
 
 	/* keep the reference to the ruleset */
-	return PTR_ERR_OR_ZERO(ruleset);
+	return err;
 }
 
 void mlxsw_sp_flower_tmplt_destroy(struct mlxsw_sp *mlxsw_sp,
-- 
2.55.0