From: Michael S. Tsirkin <mst@redhat.com>
Date: Tue, 13 May 2014 09:33:16 +0000 (+0300)
Subject: usb: fix up post load checks
X-Git-Tag: qemu-xen-4.5.1-rc1~9
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=bedbc31c141f712716ddc8933bd0a52abd0b1c8a;p=qemu-upstream-4.5-testing.git

usb: fix up post load checks

Correct post load checks:
1. dev->setup_len == sizeof(dev->data_buf)
    seems fine, no need to fail migration
2. When state is DATA, passing index > len
   will cause memcpy with negative length,
   resulting in heap overflow

First of the issues was reported by dgilbert.

Reported-by: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Juan Quintela <quintela@redhat.com>
---

diff --git a/hw/usb/bus.c b/hw/usb/bus.c
index e48b19fc2..ff1dfe6a6 100644
--- a/hw/usb/bus.c
+++ b/hw/usb/bus.c
@@ -51,8 +51,8 @@ static int usb_device_post_load(void *opaque, int version_id)
     }
     if (dev->setup_index < 0 ||
         dev->setup_len < 0 ||
-        dev->setup_index >= sizeof(dev->data_buf) ||
-        dev->setup_len >= sizeof(dev->data_buf)) {
+        dev->setup_index > dev->setup_len ||
+        dev->setup_len > sizeof(dev->data_buf)) {
         return -EINVAL;
     }
     return 0;