[PATCH AUTOSEL 5.5 304/542] crypto: atmel-sha - fix error handling when setting hmac key

From: Sasha Levin
Date: Fri Feb 14 2020 - 13:03:12 EST


From: Eric Biggers <ebiggers@xxxxxxxxxx>

[ Upstream commit b529f1983b2dcc46354f311feda92e07b6e9e2da ]

HMAC keys can be of any length, and atmel_sha_hmac_key_set() can only
fail due to -ENOMEM. But atmel_sha_hmac_setkey() incorrectly treated
any error as a "bad key length" error. Fix it to correctly propagate
the -ENOMEM error code and not set any tfm result flags.

Fixes: 81d8750b2b59 ("crypto: atmel-sha - add support to hmac(shaX)")
Cc: Nicolas Ferre <nicolas.ferre@xxxxxxxxxxxxx>
Cc: Alexandre Belloni <alexandre.belloni@xxxxxxxxxxx>
Cc: Ludovic Desroches <ludovic.desroches@xxxxxxxxxxxxx>
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Reviewed-by: Tudor Ambarus <tudor.ambarus@xxxxxxxxxxxxx>
Signed-off-by: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/crypto/atmel-sha.c | 7 +------
1 file changed, 1 insertion(+), 6 deletions(-)

diff --git a/drivers/crypto/atmel-sha.c b/drivers/crypto/atmel-sha.c
index 8ea0e4bcde0de..7394671f815bc 100644
--- a/drivers/crypto/atmel-sha.c
+++ b/drivers/crypto/atmel-sha.c
@@ -1918,12 +1918,7 @@ static int atmel_sha_hmac_setkey(struct crypto_ahash *tfm, const u8 *key,
{
struct atmel_sha_hmac_ctx *hmac = crypto_ahash_ctx(tfm);

- if (atmel_sha_hmac_key_set(&hmac->hkey, key, keylen)) {
- crypto_ahash_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN);
- return -EINVAL;
- }
-
- return 0;
+ return atmel_sha_hmac_key_set(&hmac->hkey, key, keylen);
}

static int atmel_sha_hmac_init(struct ahash_request *req)
--
2.20.1