From 6d5c900eb64107001e91e1f46bddc254dded8a59 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Mon, 24 Jan 2022 09:22:41 -0800 Subject: net/mlx5e: Use struct_group() for memcpy() region In preparation for FORTIFY_SOURCE performing compile-time and run-time field bounds checking for memcpy(), memmove(), and memset(), avoid intentionally writing across neighboring fields. Use struct_group() in struct vlan_ethhdr around members h_dest and h_source, so they can be referenced together. This will allow memcpy() and sizeof() to more easily reason about sizes, improve readability, and avoid future warnings about writing beyond the end of h_dest. "pahole" shows no size nor member offset changes to struct vlan_ethhdr. "objdump -d" shows no object code changes. Fixes: 34802a42b352 ("net/mlx5e: Do not modify the TX SKB") Signed-off-by: Kees Cook Signed-off-by: Saeed Mahameed --- include/linux/if_vlan.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) (limited to 'include') diff --git a/include/linux/if_vlan.h b/include/linux/if_vlan.h index 8420fe504927..2be4dd7e90a9 100644 --- a/include/linux/if_vlan.h +++ b/include/linux/if_vlan.h @@ -46,8 +46,10 @@ struct vlan_hdr { * @h_vlan_encapsulated_proto: packet type ID or len */ struct vlan_ethhdr { - unsigned char h_dest[ETH_ALEN]; - unsigned char h_source[ETH_ALEN]; + struct_group(addrs, + unsigned char h_dest[ETH_ALEN]; + unsigned char h_source[ETH_ALEN]; + ); __be16 h_vlan_proto; __be16 h_vlan_TCI; __be16 h_vlan_encapsulated_proto; -- cgit v1.2.3