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

stable inclusion
from stable-v5.10.155
commit adaa0f180de5236e086ddab6476c4364d922f1fd
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7M5F4

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=adaa0f180de5236e086ddab6476c4364d922f1fd



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[ Upstream commit aaab73f8 ]

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: 3cf3227a ("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>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>