crypto/ipsec_mb: fix tainted data for session

[ upstream commit 21bdbf2 ]

Downcasting a void * to struct aesni_gcm_session * caused the session
data to be treated as tainted.
Removing the void * temporary variable and adding a cast avoids this
issue.

Coverity issue: 374377
Fixes: 746825e ("crypto/ipsec_mb: move aesni_gcm PMD")

Signed-off-by: Ciara Power <ciara.power@intel.com>
Acked-by: Fan Zhang <roy.fan.zhang@intel.com>

drivers/crypto/ipsec_mb/pmd_aesni_gcm.c

@@ -713,19 +713,17 @@ aesni_gcm_process_bulk(struct rte_cryptodev *dev,
 			__rte_unused union rte_crypto_sym_ofs ofs,
 			struct rte_crypto_sym_vec *vec)
 {
-	void *sess_priv;
 	struct aesni_gcm_session *s;
 	struct gcm_context_data gdata_ctx;
 	IMB_MGR *mb_mgr;
 
-	sess_priv = get_sym_session_private_data(sess, dev->driver_id);
-	if (unlikely(sess_priv == NULL)) {
+	s = (struct aesni_gcm_session *) get_sym_session_private_data(sess,
+		dev->driver_id);
+	if (unlikely(s == NULL)) {
 		aesni_gcm_fill_error_code(vec, EINVAL);
 		return 0;
 	}
 
-	s = sess_priv;
-
 	/* get per-thread MB MGR, create one if needed */
 	mb_mgr = get_per_thread_mb_mgr();
 	if (unlikely(mb_mgr == NULL))