patch 'vhost: fix check on virtqueue access in async registration' has been queued to stable release 22.11.4

[Xueming Li]

Hi,

FYI, your patch has been queued to stable release 22.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 12/13/23. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Queued patches are on a temporary branch at:
https://git.dpdk.org/dpdk-stable/log/?h=22.11-staging

This queued commit can be viewed at:
https://git.dpdk.org/dpdk-stable/commit/?h=22.11-staging&id=7f80528fbdeb8a282ce562270d1ce6de8524595b

Thanks.

Xueming Li <xuemingl at nvidia.com>

---
>From 7f80528fbdeb8a282ce562270d1ce6de8524595b Mon Sep 17 00:00:00 2001
From: Maxime Coquelin <maxime.coquelin at redhat.com>
Date: Fri, 20 Oct 2023 10:48:01 +0200
Subject: [PATCH] vhost: fix check on virtqueue access in async registration
Cc: Xueming Li <xuemingl at nvidia.com>

[ upstream commit 867d31bed41c87510e860956ee6a67c047d98f87 ]

Acquiring the access lock is not enough to ensure
virtqueue's metadata such as vring pointers are valid.

The access status must also be checked.

Fixes: 78639d54563a ("vhost: introduce async enqueue registration API")

Signed-off-by: Maxime Coquelin <maxime.coquelin at redhat.com>
Acked-by: David Marchand <david.marchand at redhat.com>
---
 lib/vhost/vhost.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/lib/vhost/vhost.c b/lib/vhost/vhost.c
index 0188bdb6c5..695aa167dc 100644
--- a/lib/vhost/vhost.c
+++ b/lib/vhost/vhost.c
@@ -1784,7 +1784,15 @@ rte_vhost_async_channel_register(int vid, uint16_t queue_id)
 		return -1;
 
 	rte_spinlock_lock(&vq->access_lock);
+
+	if (unlikely(!vq->access_ok)) {
+		ret = -1;
+		goto out_unlock;
+	}
+
 	ret = async_channel_register(dev, vq);
+
+out_unlock:
 	rte_spinlock_unlock(&vq->access_lock);
 
 	return ret;
@@ -1840,6 +1848,11 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
 		return ret;
 	}
 
+	if (unlikely(!vq->access_ok)) {
+		ret = -1;
+		goto out_unlock;
+	}
+
 	if (!vq->async) {
 		ret = 0;
 	} else if (vq->async->pkts_inflight_n) {
@@ -1851,6 +1864,7 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
 		ret = 0;
 	}
 
+out_unlock:
 	rte_spinlock_unlock(&vq->access_lock);
 
 	return ret;
-- 
2.25.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2023-12-11 17:56:23.537453100 +0800
+++ 0009-vhost-fix-check-on-virtqueue-access-in-async-registr.patch	2023-12-11 17:56:22.887652300 +0800
@@ -1 +1 @@
-From 867d31bed41c87510e860956ee6a67c047d98f87 Mon Sep 17 00:00:00 2001
+From 7f80528fbdeb8a282ce562270d1ce6de8524595b Mon Sep 17 00:00:00 2001
@@ -4,0 +5,3 @@
+Cc: Xueming Li <xuemingl at nvidia.com>
+
+[ upstream commit 867d31bed41c87510e860956ee6a67c047d98f87 ]
@@ -12 +14,0 @@
-Cc: stable at dpdk.org
@@ -21 +23 @@
-index f7e5602913..53318a54a3 100644
+index 0188bdb6c5..695aa167dc 100644
@@ -24 +26 @@
-@@ -1859,7 +1859,15 @@ rte_vhost_async_channel_register(int vid, uint16_t queue_id)
+@@ -1784,7 +1784,15 @@ rte_vhost_async_channel_register(int vid, uint16_t queue_id)
@@ -27 +29 @@
- 	rte_rwlock_write_lock(&vq->access_lock);
+ 	rte_spinlock_lock(&vq->access_lock);
@@ -37 +39 @@
- 	rte_rwlock_write_unlock(&vq->access_lock);
+ 	rte_spinlock_unlock(&vq->access_lock);
@@ -40 +42 @@
-@@ -1911,6 +1919,11 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
+@@ -1840,6 +1848,11 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
@@ -52 +54 @@
-@@ -1922,6 +1935,7 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
+@@ -1851,6 +1864,7 @@ rte_vhost_async_channel_unregister(int vid, uint16_t queue_id)
@@ -57 +59 @@
- 	rte_rwlock_write_unlock(&vq->access_lock);
+ 	rte_spinlock_unlock(&vq->access_lock);