[PATCH net-next V2 1/3] vhost: fail early when __vhost_add_used() fails
From: Jason Wang <jasowang@redhat.com>
Date: 2025-07-14 08:48:13
Also in:
kvm, lkml, virtualization
Subsystem:
the rest, virtio host (vhost) · Maintainers:
Linus Torvalds, "Michael S. Tsirkin", Jason Wang
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@redhat.com> Signed-off-by: Jason Wang <jasowang@redhat.com> --- 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)) {
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2.39.5