[PATCH 03/14] crypto: caam - update IV only when crypto operation succeeds

[Iuliana Prodan]

From: Horia Geantă <horia.gea...@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.gea...@nxp.com>
Signed-off-by: Iuliana Prodan <iuliana.pro...@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