This patch fails vhost_add_used_n() early when __vhost_add_used()
fails to make sure used idx is not updated with stale used ring
information.
Reported-by: Eugenio Pérez <eperezma@xxxxxxxxxx>
Signed-off-by: Jason Wang <jasowang@xxxxxxxxxx>
---
drivers/vhost/vhost.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 3a5ebb973dba..d1d3912f4804 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -2775,6 +2775,9 @@ int vhost_add_used_n(struct vhost_virtqueue *vq, struct vring_used_elem *heads,
}
r = __vhost_add_used_n(vq, heads, count);
+ if (r < 0)
+ return r;
+
/* Make sure buffer is written before we update index. */
smp_wmb();
if (vhost_put_used_idx(vq)) {
--
2.39.5
