[dpdk-stable] [dpdk-dev] [PATCH v2] eal: fix dereference after null check

[wangyunjian]

From: Yunjian Wang <wangyunjian at huawei.com>

This patch fixes (dereference after null check) coverity issue.
For this reason, we should add null check at the beginning of the
function and return error directly if the 'intr_handle' is null.

Coverity issue: 357695, 357751
Fixes: 05c4105738d8 ("trace: add interrupt tracepoints")
Cc: stable at dpdk.org

Signed-off-by: Yunjian Wang <wangyunjian at huawei.com>
---
v2:
  fix code styles suggested by Ferruh Yigit
---
 lib/librte_eal/freebsd/eal_interrupts.c | 16 ++++++++++------
 lib/librte_eal/linux/eal_interrupts.c   | 16 ++++++++++------
 2 files changed, 20 insertions(+), 12 deletions(-)

diff --git a/lib/librte_eal/freebsd/eal_interrupts.c b/lib/librte_eal/freebsd/eal_interrupts.c
index 6d53d33c8..211fd4f8d 100644
--- a/lib/librte_eal/freebsd/eal_interrupts.c
+++ b/lib/librte_eal/freebsd/eal_interrupts.c
@@ -350,13 +350,15 @@ rte_intr_enable(const struct rte_intr_handle *intr_handle)
 {
 	int rc = 0;
 
-	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
+	if (intr_handle == NULL)
+		return -1;
+
+	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
 		rc = 0;
 		goto out;
 	}
 
-	if (!intr_handle || intr_handle->fd < 0 ||
-				intr_handle->uio_cfg_fd < 0) {
+	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
 		rc = -1;
 		goto out;
 	}
@@ -389,13 +391,15 @@ rte_intr_disable(const struct rte_intr_handle *intr_handle)
 {
 	int rc = 0;
 
-	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
+	if (intr_handle == NULL)
+		return -1;
+
+	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
 		rc = 0;
 		goto out;
 	}
 
-	if (!intr_handle || intr_handle->fd < 0 ||
-				intr_handle->uio_cfg_fd < 0) {
+	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
 		rc = -1;
 		goto out;
 	}
diff --git a/lib/librte_eal/linux/eal_interrupts.c b/lib/librte_eal/linux/eal_interrupts.c
index 13db5c4e8..f1bd0356c 100644
--- a/lib/librte_eal/linux/eal_interrupts.c
+++ b/lib/librte_eal/linux/eal_interrupts.c
@@ -667,13 +667,15 @@ rte_intr_enable(const struct rte_intr_handle *intr_handle)
 {
 	int rc = 0;
 
-	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
+	if (intr_handle == NULL)
+		return -1;
+
+	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
 		rc = 0;
 		goto out;
 	}
 
-	if (!intr_handle || intr_handle->fd < 0 ||
-			intr_handle->uio_cfg_fd < 0) {
+	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
 		rc = -1;
 		goto out;
 	}
@@ -794,13 +796,15 @@ rte_intr_disable(const struct rte_intr_handle *intr_handle)
 {
 	int rc = 0;
 
-	if (intr_handle && intr_handle->type == RTE_INTR_HANDLE_VDEV) {
+	if (intr_handle == NULL)
+		return -1;
+
+	if (intr_handle->type == RTE_INTR_HANDLE_VDEV) {
 		rc = 0;
 		goto out;
 	}
 
-	if (!intr_handle || intr_handle->fd < 0 ||
-					intr_handle->uio_cfg_fd < 0) {
+	if (intr_handle->fd < 0 || intr_handle->uio_cfg_fd < 0) {
 		rc = -1;
 		goto out;
 	}
-- 
2.23.0