[dpdk-dev] [PATCH] examples/vhost: fix use-after-free on drain vhost

[Wenwu Ma <wenwux.ma@intel.com>]

When a vdev is removed in destroy_device function,
the corresponding vhost_txbuff[vdev->vid] will also
be free, but the vhost_txbuff[vdev->vid] may still
be used in the drain_vhost function, which will cause
an error of heap-use-after-free. Therefore, before
accessing vhost_txbuff[vdev->vid], we need to check
whether the vdev has been removed, if so, let's skip
this vdev.

Signed-off-by: Wenwu Ma <wenwux.ma@intel.com>
---
 examples/vhost/main.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/examples/vhost/main.c b/examples/vhost/main.c
index d0bf1f31e3..1f6f7be8e3 100644
--- a/examples/vhost/main.c
+++ b/examples/vhost/main.c
@@ -916,6 +916,9 @@ drain_vhost_table(void)
 	uint64_t cur_tsc;
 
 	TAILQ_FOREACH(vdev, &vhost_dev_list, global_vdev_entry) {
+		if (unlikely(vdev->remove == 1))
+			continue;
+
 		vhost_txq = vhost_txbuff[lcore_id * MAX_VHOST_DEVICE
 						+ vdev->vid];
 
-- 
2.25.1