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

jira LE-2157
cve CVE-2024-43864
Rebuild_History Non-Buildable kernel-5.14.0-503.14.1.el9_5
commit-author Chris Mi <cmi@nvidia.com>
commit 025f2b8

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: 94ceffb ("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>
(cherry picked from commit 025f2b8)
	Signed-off-by: Jonathan Maple <jmaple@ciq.com>

Author: PlaidCat

drivers/net/ethernet/mellanox/mlx5/core/en/tc_ct.c

@@ -920,6 +920,7 @@ mlx5_tc_ct_entry_replace_rule(struct mlx5_tc_ct_priv *ct_priv,
 	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);