Received-SPF: pass (google.com: best guess record for domain of linux-crypto-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Iuliana Prodan <iuliana.prodan@nxp.com>
To:     Herbert Xu <herbert@gondor.apana.org.au>,
        Horia Geanta <horia.geanta@nxp.com>,
        Aymen Sghaier <aymen.sghaier@nxp.com>
Cc:     "David S. Miller" <davem@davemloft.net>,
        linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-imx <linux-imx@nxp.com>
Subject: [PATCH v3 03/14] crypto: caam - update IV only when crypto operation succeeds
Date:   Thu, 25 Jul 2019 16:58:15 +0300
Message-Id: <1564063106-9552-4-git-send-email-iuliana.prodan@nxp.com>
In-Reply-To: <1564063106-9552-1-git-send-email-iuliana.prodan@nxp.com>
References: <1564063106-9552-1-git-send-email-iuliana.prodan@nxp.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-crypto-owner@vger.kernel.org
Precedence: bulk

From: Horia Geantă <horia.geanta@nxp.com>

skcipher encryption might fail and in some cases, like (invalid) input
length smaller then block size, updating the IV would lead to panic
due to copying from a negative offset (req->cryptlen - ivsize).

Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Iuliana Prodan <iuliana.prodan@nxp.com>
---
 drivers/crypto/caam/caamalg.c     | 5 ++---
 drivers/crypto/caam/caamalg_qi.c  | 4 +++-
 drivers/crypto/caam/caamalg_qi2.c | 8 ++++++--
 3 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/drivers/crypto/caam/caamalg.c b/drivers/crypto/caam/caamalg.c
index 06b4f2d..28d55a0 100644
--- a/drivers/crypto/caam/caamalg.c
+++ b/drivers/crypto/caam/caamalg.c
@@ -990,10 +990,9 @@ static void skcipher_encrypt_done(struct device *jrdev, u32 *desc, u32 err,
 	 * ciphertext block (CBC mode) or last counter (CTR mode).
 	 * This is used e.g. by the CTS mode.
 	 */
-	if (ivsize) {
+	if (ivsize && !ecode) {
 		memcpy(req->iv, (u8 *)edesc->sec4_sg + edesc->sec4_sg_bytes,
 		       ivsize);
-
 		print_hex_dump_debug("dstiv  @"__stringify(__LINE__)": ",
 				     DUMP_PREFIX_ADDRESS, 16, 4, req->iv,
 				     edesc->src_nents > 1 ? 100 : ivsize, 1);
@@ -1030,7 +1029,7 @@ static void skcipher_decrypt_done(struct device *jrdev, u32 *desc, u32 err,
 	 * ciphertext block (CBC mode) or last counter (CTR mode).
 	 * This is used e.g. by the CTS mode.
 	 */
-	if (ivsize) {
+	if (ivsize && !ecode) {
 		memcpy(req->iv, (u8 *)edesc->sec4_sg + edesc->sec4_sg_bytes,
 		       ivsize);
 
diff --git a/drivers/crypto/caam/caamalg_qi.c b/drivers/crypto/caam/caamalg_qi.c
index ab263b1..66531d6 100644
--- a/drivers/crypto/caam/caamalg_qi.c
+++ b/drivers/crypto/caam/caamalg_qi.c
@@ -1201,7 +1201,9 @@ static void skcipher_done(struct caam_drv_req *drv_req, u32 status)
 	 * ciphertext block (CBC mode) or last counter (CTR mode).
 	 * This is used e.g. by the CTS mode.
 	 */
-	memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes, ivsize);
+	if (!ecode)
+		memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes,
+		       ivsize);
 
 	qi_cache_free(edesc);
 	skcipher_request_complete(req, ecode);
diff --git a/drivers/crypto/caam/caamalg_qi2.c b/drivers/crypto/caam/caamalg_qi2.c
index 2681581..bc370af 100644
--- a/drivers/crypto/caam/caamalg_qi2.c
+++ b/drivers/crypto/caam/caamalg_qi2.c
@@ -1358,7 +1358,9 @@ static void skcipher_encrypt_done(void *cbk_ctx, u32 status)
 	 * ciphertext block (CBC mode) or last counter (CTR mode).
 	 * This is used e.g. by the CTS mode.
 	 */
-	memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes, ivsize);
+	if (!ecode)
+		memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes,
+		       ivsize);
 
 	qi_cache_free(edesc);
 	skcipher_request_complete(req, ecode);
@@ -1394,7 +1396,9 @@ static void skcipher_decrypt_done(void *cbk_ctx, u32 status)
 	 * ciphertext block (CBC mode) or last counter (CTR mode).
 	 * This is used e.g. by the CTS mode.
 	 */
-	memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes, ivsize);
+	if (!ecode)
+		memcpy(req->iv, (u8 *)&edesc->sgt[0] + edesc->qm_sg_bytes,
+		       ivsize);
 
 	qi_cache_free(edesc);
 	skcipher_request_complete(req, ecode);
-- 
2.1.0