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Blame 0006-virtio-out-of-bounds-buffer-write-on-invalid-state-l.patch

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From 23f0db5c309893195025bc75402f3f9e1b4de743 Mon Sep 17 00:00:00 2001
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From: "Michael S. Tsirkin" <mst@redhat.com>
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Date: Thu, 3 Apr 2014 19:51:14 +0300
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Subject: [PATCH] virtio: out-of-bounds buffer write on invalid state load
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CVE-2013-4151 QEMU 1.0 out-of-bounds buffer write in
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virtio_load@hw/virtio/virtio.c
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So we have this code since way back when:
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    num = qemu_get_be32(f);
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    for (i = 0; i < num; i++) {
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        vdev->vq[i].vring.num = qemu_get_be32(f);
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array of vqs has size VIRTIO_PCI_QUEUE_MAX, so
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on invalid input this will write beyond end of buffer.
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Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
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Reviewed-by: Michael Roth <mdroth@linux.vnet.ibm.com>
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Signed-off-by: Juan Quintela <quintela@redhat.com>
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(cherry picked from commit cc45995294b92d95319b4782750a3580cabdbc0c)
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---
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 hw/virtio/virtio.c | 8 +++++++-
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 1 file changed, 7 insertions(+), 1 deletion(-)
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diff --git a/hw/virtio/virtio.c b/hw/virtio/virtio.c
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index aeabf3a..05f05e7 100644
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--- a/hw/virtio/virtio.c
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+++ b/hw/virtio/virtio.c
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@@ -891,7 +891,8 @@ int virtio_set_features(VirtIODevice *vdev, uint32_t val)
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 int virtio_load(VirtIODevice *vdev, QEMUFile *f)
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 {
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-    int num, i, ret;
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+    int i, ret;
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+    uint32_t num;
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     uint32_t features;
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     uint32_t supported_features;
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     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));
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@@ -919,6 +920,11 @@ int virtio_load(VirtIODevice *vdev, QEMUFile *f)
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     num = qemu_get_be32(f);
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+    if (num > VIRTIO_PCI_QUEUE_MAX) {
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+        error_report("Invalid number of PCI queues: 0x%x", num);
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+        return -1;
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+    }
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+
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     for (i = 0; i < num; i++) {
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         vdev->vq[i].vring.num = qemu_get_be32(f);
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         if (k->has_variable_vring_alignment) {