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| author | Li Qiang <liq3ea@163.com> | 2020-09-19 01:27:06 -0700 |
|---|---|---|
| committer | Michael S. Tsirkin <mst@redhat.com> | 2020-09-29 02:15:24 -0400 |
| commit | 2d69eba5fe52045b2c8b0d04fd3806414352afc1 (patch) | |
| tree | 6790a25a6d1fca04016cd6455d5710a59b3e5b8a /hw | |
| parent | a6704a34cf02add13964149e0de6453ae62bd9db (diff) | |
| download | qemu-2d69eba5fe52045b2c8b0d04fd3806414352afc1.zip qemu-2d69eba5fe52045b2c8b0d04fd3806414352afc1.tar.gz qemu-2d69eba5fe52045b2c8b0d04fd3806414352afc1.tar.bz2 | |
virtio: update MemoryRegionCaches when guest set bad features
Current the 'virtio_set_features' only update the 'MemorRegionCaches'
when the 'virtio_set_features_nocheck' return '0' which means it is
not bad features. However the guest can still trigger the access of the
used vring after set bad features. In this situation it will cause assert
failure in 'ADDRESS_SPACE_ST_CACHED'.
Buglink: https://bugs.launchpad.net/qemu/+bug/1890333
Fixes: db812c4073c7 ("virtio: update MemoryRegionCaches when guest negotiates features")
Reported-by: Alexander Bulekov <alxndr@bu.edu>
Signed-off-by: Li Qiang <liq3ea@163.com>
Message-Id: <20200919082706.6703-1-liq3ea@163.com>
Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Diffstat (limited to 'hw')
| -rw-r--r-- | hw/virtio/virtio.c | 17 |
1 files changed, 8 insertions, 9 deletions
diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c index a2edb4f..6f8f865 100644 --- a/hw/virtio/virtio.c +++ b/hw/virtio/virtio.c @@ -2963,17 +2963,16 @@ int virtio_set_features(VirtIODevice *vdev, uint64_t val) return -EINVAL; } ret = virtio_set_features_nocheck(vdev, val); - if (!ret) { - if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) { - /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches. */ - int i; - for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { - if (vdev->vq[i].vring.num != 0) { - virtio_init_region_cache(vdev, i); - } + if (virtio_vdev_has_feature(vdev, VIRTIO_RING_F_EVENT_IDX)) { + /* VIRTIO_RING_F_EVENT_IDX changes the size of the caches. */ + int i; + for (i = 0; i < VIRTIO_QUEUE_MAX; i++) { + if (vdev->vq[i].vring.num != 0) { + virtio_init_region_cache(vdev, i); } } - + } + if (!ret) { if (!virtio_device_started(vdev, vdev->status) && !virtio_vdev_has_feature(vdev, VIRTIO_F_VERSION_1)) { vdev->start_on_kick = true; |