From aaab73f8fba4fd38f4d2617440d541a1c334e819 Mon Sep 17 00:00:00 2001
From: Sabrina Dubroca <sd@queasysnail.net>
Date: Wed, 2 Nov 2022 22:33:16 +0100
Subject: [PATCH] macsec: clear encryption keys from the stack after setting up offload
Git-commit: aaab73f8fba4fd38f4d2617440d541a1c334e819
Patch-mainline: v6.1-rc5
References: git-fixes

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: 3cf3227a21d1 ("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>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/net/macsec.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/macsec.c b/drivers/net/macsec.c
index 700a8f96c6c2..85376d2f24ca 100644
--- 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;
 	}
-- 
2.35.3