[dpdk-dev] [PATCH v5 11/12] cryptodev: add reference count to session private data

[Fan Zhang <roy.fan.zhang@intel.com>]

This patch adds a refcnt field to every session private data in the
cryptodev symmetric session. The counter is used to prevent freeing
symmetric session blindly before it is not cleared by every type of
crypto device in use.

Signed-off-by: Fan Zhang <roy.fan.zhang@intel.com>
Acked-by: Fiona Trahe <fiona.trahe@intel.com>
---
 doc/guides/prog_guide/img/cryptodev_sym_sess.svg |  7 +++++++
 doc/guides/rel_notes/release_19_02.rst           |  6 ++++++
 lib/librte_cryptodev/rte_cryptodev.c             | 14 +++++++++-----
 lib/librte_cryptodev/rte_cryptodev.h             |  1 +
 4 files changed, 23 insertions(+), 5 deletions(-)

diff --git a/doc/guides/prog_guide/img/cryptodev_sym_sess.svg b/doc/guides/prog_guide/img/cryptodev_sym_sess.svg
index 20059cc0f..7d7052c38 100644
--- a/doc/guides/prog_guide/img/cryptodev_sym_sess.svg
+++ b/doc/guides/prog_guide/img/cryptodev_sym_sess.svg
@@ -308,6 +308,13 @@
        class="st2"
        y="189.4823"
        x="-185.78569">user_data</text>
+<text
+       transform="scale(0.71276665,1.4029837)"
+       style="font-size:14.02988338px;font-family:Calibri;overflow:visible;color-interpolation-filters:sRGB;fill:#386288;fill-rule:evenodd;stroke-width:1.40298378;stroke-linecap:square;stroke-miterlimit:3"
+       id="text24-5-5-1-4"
+       class="st2"
+       y="129.23468"
+       x="-204.95244">uint16_t refcnt;</text>
 </g><g
      transform="matrix(1.022976,0,0,0.71529071,199.82034,-39.936699)"
      id="shape19-6-5"><title
diff --git a/doc/guides/rel_notes/release_19_02.rst b/doc/guides/rel_notes/release_19_02.rst
index b488a6d35..a79298ce3 100644
--- a/doc/guides/rel_notes/release_19_02.rst
+++ b/doc/guides/rel_notes/release_19_02.rst
@@ -110,6 +110,12 @@ New Features
   Added a new performance test tool to test the compressdev PMD. The tool tests
   compression ratio and compression throughput.
 
+* **Added security checks to cryptodev symmetric session operations.**
+
+  Added a set of security checks to the access cryptodev symmetric session.
+  The checks include the session's user data read/write check and the
+  session private data referencing status check while freeing a session.
+
 
 Removed Items
 -------------
diff --git a/lib/librte_cryptodev/rte_cryptodev.c b/lib/librte_cryptodev/rte_cryptodev.c
index d01bb110e..654c39fe1 100644
--- a/lib/librte_cryptodev/rte_cryptodev.c
+++ b/lib/librte_cryptodev/rte_cryptodev.c
@@ -1216,7 +1216,7 @@ rte_cryptodev_sym_session_init(uint8_t dev_id,
 
 	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->sym_session_configure, -ENOTSUP);
 
-	if (sess->sess_data[index].data == NULL) {
+	if (sess->sess_data[index].refcnt == 0) {
 		ret = dev->dev_ops->sym_session_configure(dev, xforms,
 							sess, mp);
 		if (ret < 0) {
@@ -1227,6 +1227,7 @@ rte_cryptodev_sym_session_init(uint8_t dev_id,
 		}
 	}
 
+	sess->sess_data[index].refcnt++;
 	return 0;
 }
 
@@ -1372,12 +1373,17 @@ rte_cryptodev_sym_session_clear(uint8_t dev_id,
 		struct rte_cryptodev_sym_session *sess)
 {
 	struct rte_cryptodev *dev;
+	uint8_t driver_id;
 
 	dev = rte_cryptodev_pmd_get_dev(dev_id);
 
 	if (dev == NULL || sess == NULL)
 		return -EINVAL;
 
+	driver_id = dev->driver_id;
+	if (--sess->sess_data[driver_id].refcnt != 0)
+		return -EBUSY;
+
 	RTE_FUNC_PTR_OR_ERR_RET(*dev->dev_ops->sym_session_clear, -ENOTSUP);
 
 	dev->dev_ops->sym_session_clear(dev, sess);
@@ -1407,16 +1413,14 @@ int
 rte_cryptodev_sym_session_free(struct rte_cryptodev_sym_session *sess)
 {
 	uint8_t i;
-	void *sess_priv;
 	struct rte_mempool *sess_mp;
 
 	if (sess == NULL)
 		return -EINVAL;
 
 	/* Check that all device private data has been freed */
-	for (i = 0; i < nb_drivers; i++) {
-		sess_priv = get_sym_session_private_data(sess, i);
-		if (sess_priv != NULL)
+	for (i = 0; i < sess->nb_drivers; i++) {
+		if (sess->sess_data[i].refcnt != 0)
 			return -EBUSY;
 	}
 
diff --git a/lib/librte_cryptodev/rte_cryptodev.h b/lib/librte_cryptodev/rte_cryptodev.h
index 232cd1aa8..7652102de 100644
--- a/lib/librte_cryptodev/rte_cryptodev.h
+++ b/lib/librte_cryptodev/rte_cryptodev.h
@@ -963,6 +963,7 @@ struct rte_cryptodev_sym_session {
 	/**< session user data will be placed after sess_data */
 	__extension__ struct {
 		void *data;
+		uint16_t refcnt;
 	} sess_data[0];
 	/**< Driver specific session material, variable size */
 };
-- 
2.13.6