net: hsr: fix mac_len checks

[ Upstream commit 48b491a5cc74333c4a6a82fe21cea42c055a3b0b ]

Commit 2e9f60932a2c ("net: hsr: check skb can contain struct hsr_ethhdr
in fill_frame_info") added the following which resulted in -EINVAL
always being returned:
	if (skb->mac_len < sizeof(struct hsr_ethhdr))
		return -EINVAL;

mac_len was not being set correctly so this check completely broke
HSR/PRP since it was always 14, not 20.

Set mac_len correctly and modify the mac_len checks to test in the
correct places since sometimes it is legitimately 14.

Fixes: 2e9f60932a2c ("net: hsr: check skb can contain struct hsr_ethhdr in fill_frame_info")
Signed-off-by: George McCollister <george.mccollister@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
George McCollister
2021-05-24 13:50:54 -05:00
committed by Greg Kroah-Hartman
parent a6a0af3c90
commit f6442ee08f
5 changed files with 34 additions and 21 deletions

View File

@@ -58,12 +58,11 @@ static rx_handler_result_t hsr_handle_frame(struct sk_buff **pskb)
goto finish_pass;
skb_push(skb, ETH_HLEN);
if (skb_mac_header(skb) != skb->data) {
WARN_ONCE(1, "%s:%d: Malformed frame at source port %s)\n",
__func__, __LINE__, port->dev->name);
goto finish_consume;
}
skb_reset_mac_header(skb);
if ((!hsr->prot_version && protocol == htons(ETH_P_PRP)) ||
protocol == htons(ETH_P_HSR))
skb_set_network_header(skb, ETH_HLEN + HSR_HLEN);
skb_reset_mac_len(skb);
hsr_forward_skb(skb, port);