macsec: clear encryption keys from the stack after setting up offload

macsec_add_rxsa and macsec_add_txsa copy the key to an on-stack
offloading context to pass it to the drivers, but leaves it there when
it's done. Clear it with memzero_explicit as soon as it's not needed
anymore.

Fixes: 98e38d6db896 ("net: macsec: hardware offloading infrastructure")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Reviewed-by: Antoine Tenart <atenart@kernel.org>
Reviewed-by: Leon Romanovsky <leonro@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 700a8f96c6c2fac79c5f4613d2dd6c478665afde..85376d2f24ca8a4ab49f9ce174512326af5199d3 100644 (file)
--- a/drivers/net/macsec.c
+++ b/drivers/net/macsec.c
@@ -1839,6 +1839,7 @@ static int macsec_add_rxsa(struct sk_buff *skb, struct genl_info *info)
                       secy->key_len);
 
                err = macsec_offload(ops->mdo_add_rxsa, &ctx);
+               memzero_explicit(ctx.sa.key, secy->key_len);
                if (err)
                        goto cleanup;
        }
@@ -2081,6 +2082,7 @@ static int macsec_add_txsa(struct sk_buff *skb, struct genl_info *info)
                       secy->key_len);
 
                err = macsec_offload(ops->mdo_add_txsa, &ctx);
+               memzero_explicit(ctx.sa.key, secy->key_len);
                if (err)
                        goto cleanup;
        }