net/mlx5e: Fix CT entry update leaks of modify header context

The cited commit allocates a new modify header to replace the old
one when updating CT entry. But if failed to allocate a new one, eg.
exceed the max number firmware can support, modify header will be
an error pointer that will trigger a panic when deallocating it. And
the old modify header point is copied to old attr. When the old
attr is freed, the old modify header is lost.

Fix it by restoring the old attr to attr when failed to allocate a
new modify header context. So when the CT entry is freed, the right
modify header context will be freed. And the panic of accessing
error pointer is also fixed.

Fixes: 94ceffb48eac ("net/mlx5e: Implement CT entry update")
Signed-off-by: Chris Mi <cmi@nvidia.com>
Signed-off-by: Tariq Toukan <tariqt@nvidia.com>
Reviewed-by: Wojciech Drewek <wojciech.drewek@intel.com>
Link: https://patch.msgid.link/20240730061638.1831002-8-tariqt@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c
index 8cf8ba2622f2bfaa03b41cc9af0357bf8050e71e..71a168746ebe21d496612cf7f239671cd0d4cf20 100644 (file)
--- a/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c
+++ b/drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c
@@ -932,6 +932,7 @@ err_rule:
        mlx5_tc_ct_entry_destroy_mod_hdr(ct_priv, zone_rule->attr, mh);
        mlx5_put_label_mapping(ct_priv, attr->ct_attr.ct_labels_id);
 err_mod_hdr:
+       *attr = *old_attr;
        kfree(old_attr);
 err_attr:
        kvfree(spec);