Commit 88181f1d authored by Kees Cook's avatar Kees Cook Committed by David S. Miller
Browse files

cxgb3: 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 rss_hdr around members imm_data and intr_gen,
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 imm_data.

"pahole" shows no size nor member offset changes to struct rss_hdr.
"objdump -d" shows no object code changes.

Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent ec574d9e

drivers/net/ethernet/chelsio/cxgb3/sge.c

+6 −3
Original line number Diff line number Diff line
@@ -126,8 +126,10 @@ struct rsp_desc { /* response queue descriptor */ 
	struct rss_header rss_hdr;

	__be32 flags;

	__be32 len_cq;

	struct_group(immediate,

		u8 imm_data[47];

		u8 intr_gen;

	);

};



/*
@@ -925,7 +927,8 @@ static inline struct sk_buff *get_imm_packet(const struct rsp_desc *resp) 


	if (skb) {

		__skb_put(skb, IMMED_PKT_SIZE);

		skb_copy_to_linear_data(skb, resp->imm_data, IMMED_PKT_SIZE);

		BUILD_BUG_ON(IMMED_PKT_SIZE != sizeof(resp->immediate));

		skb_copy_to_linear_data(skb, &resp->immediate, IMMED_PKT_SIZE);

	}

	return skb;

}