[PATCH] crypto: sun4i-ss: erase key after use

From: Corentin Labbe
Date: Sun Sep 15 2019 - 14:35:57 EST


When a TFM is unregistered, the sun4i-ss driver does not clean the key used,
leaking it in memory.
This patch adds this absent key cleaning.

Fixes: 6298e948215f ("crypto: sunxi-ss - Add Allwinner Security System crypto accelerator")
Cc: <stable@xxxxxxxxxxxxxxx> # 4.3+
Signed-off-by: Corentin Labbe <clabbe.montjoie@xxxxxxxxx>
---
drivers/crypto/sunxi-ss/sun4i-ss-cipher.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
index fa4b1b47822e..60d99370a4ec 100644
--- a/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-cipher.c
@@ -503,6 +503,8 @@ int sun4i_ss_cipher_init(struct crypto_tfm *tfm)
void sun4i_ss_cipher_exit(struct crypto_tfm *tfm)
{
struct sun4i_tfm_ctx *op = crypto_tfm_ctx(tfm);
+
+ memzero_explicit(op->key, op->keylen);
crypto_free_sync_skcipher(op->fallback_tfm);
}

--
2.21.0