[PATCH v2 3/6] crypto: xts - drop redundant xts key check

[Vladis Dronov <vdronov@redhat.com>]

xts_fallback_setkey() in xts_aes_set_key() will now enforce key size
rule in FIPS mode when setting up the fallback algorithm keys, which
makes the check in xts_aes_set_key() redundant or unreachable. So just
drop this check.

xts_fallback_setkey() now makes a key size check in xts_verify_key():

xts_fallback_setkey()
  crypto_skcipher_setkey() [ skcipher_setkey_unaligned() ]
    cipher->setkey() { .setkey = xts_setkey }
      xts_setkey()
        xts_verify_key()

Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Reviewed-by: Eric Biggers <ebiggers@google.com>
---
 arch/s390/crypto/aes_s390.c | 4 ----
 1 file changed, 4 deletions(-)

diff --git a/arch/s390/crypto/aes_s390.c b/arch/s390/crypto/aes_s390.c
index 526c3f40f6a2..c773820e4af9 100644
--- a/arch/s390/crypto/aes_s390.c
+++ b/arch/s390/crypto/aes_s390.c
@@ -398,10 +398,6 @@ static int xts_aes_set_key(struct crypto_skcipher *tfm, const u8 *in_key,
 	if (err)
 		return err;
 
-	/* In fips mode only 128 bit or 256 bit keys are valid */
-	if (fips_enabled && key_len != 32 && key_len != 64)
-		return -EINVAL;
-
 	/* Pick the correct function code based on the key length */
 	fc = (key_len == 32) ? CPACF_KM_XTS_128 :
 	     (key_len == 64) ? CPACF_KM_XTS_256 : 0;
-- 
2.38.1