[PATCH] crypto/ipsec_mb: fix clearing snow3g digest

["weid wei.dai@picocom.com" <wei.dai@picocom.com>]

From: weid <wei.dai@picocom.com>

Before this patch, the software crypto_snow3g
clear the encrypted auth snow3g digest when
the dst mbuf is same as the src mbuf in crypto
op.

This bug can be checked by following way,
start app/dpdk-test --vdev=crypto_snow3g,
run pdcp_autotest
the case failed when i=42 in
run_test_for_one_known_vec() in test_pdcp.c.
The case is PDCP control plane auth snow3g gen
+ cipher snow3g enc.
The case failed because the last 4 bytes are
cleared in last for() loop in line 167 in
process_snow3g_cipher_op() in pmd_snow3g.c .

Fixes: 5208d68d30cb ("crypto/ipsec_mb: support snow3g digest appended
ops")

Signed-off-by: weid <wei.dai@picocom.com>
---
 drivers/crypto/ipsec_mb/pmd_snow3g.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/crypto/ipsec_mb/pmd_snow3g.c b/drivers/crypto/ipsec_mb/pmd_snow3g.c
index b3c3b05a8a..35fe23c157 100644
--- a/drivers/crypto/ipsec_mb/pmd_snow3g.c
+++ b/drivers/crypto/ipsec_mb/pmd_snow3g.c
@@ -157,7 +157,8 @@ process_snow3g_cipher_op(struct ipsec_mb_qp *qp, struct rte_crypto_op **ops,
 	for (i = 0; i < num_ops; i++) {
 		if ((session->op == IPSEC_MB_OP_HASH_VERIFY_THEN_DECRYPT ||
 			session->op == IPSEC_MB_OP_HASH_GEN_THEN_ENCRYPT) &&
-				ops[i]->sym->m_dst != NULL) {
+				ops[i]->sym->m_dst != NULL &&
+				ops[i]->sym->m_dst != ops[i]->sym->m_src) {
 			digest_appended[i] =
 				snow3g_digest_appended_in_src(ops[i]);
 			/* Clear unencrypted digest from
-- 
2.51.0.windows.1