From d89318bbdf2b8f472d7f1225bbe44ead7b57c5e4 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 26 Sep 2022 17:40:33 -0700 Subject: [PATCH] mlxsw: core_acl_flex_actions: Split memcpy() of struct flow_action_cookie flexible array To work around a misbehavior of the compiler's ability to see into composite flexible array structs (as detailed in the coming memcpy() hardening series[1]), split the memcpy() of the header and the payload so no false positive run-time overflow warning will be generated. [1] https://lore.kernel.org/linux-hardening/20220901065914.1417829-2-keescook@chromium.org Cc: Ido Schimmel Signed-off-by: Kees Cook Reviewed-by: Gustavo A. R. Silva Reviewed-by: Petr Machata Link: https://lore.kernel.org/r/20220927004033.1942992-1-keescook@chromium.org Signed-off-by: Jakub Kicinski --- drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c b/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c index 636db9a874577..9dfe7148199f9 100644 --- a/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c +++ b/drivers/net/ethernet/mellanox/mlxsw/core_acl_flex_actions.c @@ -737,8 +737,9 @@ mlxsw_afa_cookie_create(struct mlxsw_afa *mlxsw_afa, if (!cookie) return ERR_PTR(-ENOMEM); refcount_set(&cookie->ref_count, 1); - memcpy(&cookie->fa_cookie, fa_cookie, - sizeof(*fa_cookie) + fa_cookie->cookie_len); + cookie->fa_cookie = *fa_cookie; + memcpy(cookie->fa_cookie.cookie, fa_cookie->cookie, + fa_cookie->cookie_len); err = rhashtable_insert_fast(&mlxsw_afa->cookie_ht, &cookie->ht_node, mlxsw_afa_cookie_ht_params); -- 2.30.2