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From fa97dc2d48b476ea98199d808d3248d285987e99 Mon Sep 17 00:00:00 2001
From: Nicolas Toromanoff <nicolas.toromanoff@foss.st.com>
Date: Tue, 30 Nov 2021 08:54:59 +0100
Subject: [PATCH] crypto: stm32/cryp - fix lrw chaining mode
Git-commit: fa97dc2d48b476ea98199d808d3248d285987e99
Patch-mainline: v5.17-rc1
References: git-fixes

This fixes the lrw autotest if lrw uses the CRYP as the AES block cipher
provider (as ecb(aes)). At end of request, CRYP should not update the IV
in case of ECB chaining mode. Indeed the ECB chaining mode never uses
the IV, but the software LRW chaining mode uses the IV field as
a counter and due to the (unexpected) update done by CRYP while the AES
block process, the counter get a wrong value when the IV overflow.

Fixes: 5f49f18d27cd ("crypto: stm32/cryp - update to return iv_out")

Signed-off-by: Nicolas Toromanoff <nicolas.toromanoff@foss.st.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: Takashi Iwai <tiwai@suse.de>

---
 drivers/crypto/stm32/stm32-cryp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
index 3f71d927843c..d3aa0afbe365 100644
--- a/drivers/crypto/stm32/stm32-cryp.c
+++ b/drivers/crypto/stm32/stm32-cryp.c
@@ -644,7 +644,7 @@ static void stm32_cryp_finish_req(struct stm32_cryp *cryp, int err)
 		/* Phase 4 : output tag */
 		err = stm32_cryp_read_auth_tag(cryp);
 
-	if (!err && (!(is_gcm(cryp) || is_ccm(cryp))))
+	if (!err && (!(is_gcm(cryp) || is_ccm(cryp) || is_ecb(cryp))))
 		stm32_cryp_get_iv(cryp);
 
 	if (cryp->sgs_copied) {
-- 
2.31.1