[PATCH 3/6] crypto: eip93: reject HMAC requests before setkey

[Jihong Min]

HMAC requests need the precomputed ipad/opad state installed by setkey().
Using an HMAC tfm before setkey() initializes the request with an all-zero
ipad and produces invalid hardware input.

Reject those requests during hash init so the failure is explicit.

Fixes: 9739f5f93b78 ("crypto: eip93 - Add Inside Secure SafeXcel EIP-93 crypto engine support")
Originally-by: Mieczyslaw Nalewaj <namiltd@xxxxxxxxx>
Assisted-by: Codex:gpt-5.5
Signed-off-by: Jihong Min <hurryman2212@xxxxxxxxx>
---
 drivers/crypto/inside-secure/eip93/eip93-hash.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/crypto/inside-secure/eip93/eip93-hash.c b/drivers/crypto/inside-secure/eip93/eip93-hash.c
index 63bb6c4670cb..060e90c5eaa7 100644
--- a/drivers/crypto/inside-secure/eip93/eip93-hash.c
+++ b/drivers/crypto/inside-secure/eip93/eip93-hash.c
@@ -300,6 +300,9 @@ static int eip93_hash_init(struct ahash_request *req)
 	struct eip93_hash_ctx *ctx = crypto_ahash_ctx(ahash);
 	struct sa_state *sa_state = &rctx->sa_state;
 
+	if (IS_HMAC(ctx->flags) && !memchr_inv(ctx->ipad, 0, SHA256_BLOCK_SIZE))
+		return -EINVAL;
+
 	memset(sa_state->state_byte_cnt, 0, sizeof(u32) * 2);
 	eip93_hash_init_sa_state_digest(ctx->flags & EIP93_HASH_MASK,
 					sa_state->state_i_digest);
-- 
2.53.0