macsec: delete new rxsc when offload fails

Currently we get an inconsistent state:
 - netlink returns the error to userspace
 - the RXSC is installed but not offloaded

Then the device could get confused when we try to add an RXSA, because
the RXSC isn't supposed to exist.

Fixes: 3cf3227a ("net: macsec: hardware offloading infrastructure")
Signed-off-by: NSabrina Dubroca <sd@queasysnail.net>
Reviewed-by: NAntoine Tenart <atenart@kernel.org>
Reviewed-by: NLeon Romanovsky <leonro@nvidia.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

drivers/net/macsec.c

@@ -1876,7 +1876,6 @@ static int macsec_add_rxsc(struct sk_buff *skb, struct genl_info *info)
 	struct macsec_rx_sc *rx_sc;
 	struct nlattr *tb_rxsc[MACSEC_RXSC_ATTR_MAX + 1];
 	struct macsec_secy *secy;
-	bool was_active;
 	int ret;
 
 	if (!attrs[MACSEC_ATTR_IFINDEX])
@@ -1904,7 +1903,6 @@ static int macsec_add_rxsc(struct sk_buff *skb, struct genl_info *info)
 		return PTR_ERR(rx_sc);
 	}
 
-	was_active = rx_sc->active;
 	if (tb_rxsc[MACSEC_RXSC_ATTR_ACTIVE])
 		rx_sc->active = !!nla_get_u8(tb_rxsc[MACSEC_RXSC_ATTR_ACTIVE]);
 
@@ -1931,7 +1929,8 @@ static int macsec_add_rxsc(struct sk_buff *skb, struct genl_info *info)
 	return 0;
 
 cleanup:
-	rx_sc->active = was_active;
+	del_rx_sc(secy, sci);
+	free_rx_sc(rx_sc);
 	rtnl_unlock();
 	return ret;
 }