File vbox-denial-of-service-fix.diff of Package virtualbox-ose

Index: VirtualBox-2.0.6/include/VBox/VBoxGuestLib.h
===================================================================
--- VirtualBox-2.0.6.orig/include/VBox/VBoxGuestLib.h
+++ VirtualBox-2.0.6/include/VBox/VBoxGuestLib.h
@@ -129,6 +129,18 @@ DECLVBGL(int) VbglGRPerform (VMMDevReque
  * @return VBox status code.
  */
 DECLVBGL(void) VbglGRFree (VMMDevRequestHeader *pReq);
+
+/**
+ * Verify the generic request header.
+ *
+ * @param pReq     pointer the request header structure.
+ * @param cbReq    size of the request memory block. It should be equal to the request size
+ *                 for fixed size requests. It can be greater than the request size for
+ *                 variable size requests.
+ *
+ * @return VBox status code.
+ */
+DECLVBGL(int) VbglGRVerify (const VMMDevRequestHeader *pReq, size_t cbReq);
 /** @} */
 
 #ifdef VBOX_WITH_HGCM
Index: VirtualBox-2.0.6/src/VBox/Additions/common/VBoxGuest/VBoxGuest.cpp
===================================================================
--- VirtualBox-2.0.6.orig/src/VBox/Additions/common/VBoxGuest/VBoxGuest.cpp
+++ VirtualBox-2.0.6/src/VBox/Additions/common/VBoxGuest/VBoxGuest.cpp
@@ -767,6 +767,13 @@ static int VBoxGuestCommonIOCtl_VMMReque
              cbData, cbReq, pReqHdr->requestType));
         return VERR_INVALID_PARAMETER;
     }
+    int rc = VbglGRVerify(pReqHdr, cbData);
+    if (RT_FAILURE(rc))
+    {
+        Log(("VBoxGuestCommonIOCtl: VMMREQUEST: invalid header: size %#x, expected >= %#x (hdr); type=%#x; rc %d!!\n",
+             cbData, cbReq, enmType, rc));
+        return rc;
+    }
 
     /*
      * Make a copy of the request in the physical memory heap so
@@ -776,7 +783,7 @@ static int VBoxGuestCommonIOCtl_VMMReque
      * it does makes things a bit simpler wrt to phys address.)
      */
     VMMDevRequestHeader *pReqCopy;
-    int rc = VbglGRAlloc(&pReqCopy, cbReq, pReqHdr->requestType);
+    rc = VbglGRAlloc(&pReqCopy, cbReq, pReqHdr->requestType);
     if (RT_FAILURE(rc))
     {
         Log(("VBoxGuestCommonIOCtl: VMMREQUEST: failed to allocate %u (%#x) bytes to cache the request. rc=%d!!\n",
Index: VirtualBox-2.0.6/src/VBox/Additions/common/VBoxGuestLib/GenericRequest.cpp
===================================================================
--- VirtualBox-2.0.6.orig/src/VBox/Additions/common/VBoxGuestLib/GenericRequest.cpp
+++ VirtualBox-2.0.6/src/VBox/Additions/common/VBoxGuestLib/GenericRequest.cpp
@@ -26,6 +26,72 @@
 #include <iprt/string.h>
 #include <iprt/assert.h>
 
+DECLVBGL(int) VbglGRVerify (const VMMDevRequestHeader *pReq, size_t cbReq)
+{
+    if (!pReq || cbReq < sizeof (VMMDevRequestHeader))
+    {
+        dprintf(("VbglGRVerify: Invalid parameter: pReq = %p, cbReq = %d\n", pReq, cbReq));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    if (pReq->size > cbReq)
+    {
+        dprintf(("VbglGRVerify: request size %d > buffer size %d\n", pReq->size, cbReq));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    /* The request size must correspond to the request type. */
+    size_t cbReqExpected = vmmdevGetRequestSize(pReq->requestType);
+
+    if (cbReq < cbReqExpected)
+    {
+        dprintf(("VbglGRVerify: buffer size %d < expected size %d\n", cbReq, cbReqExpected));
+        return VERR_INVALID_PARAMETER;
+    }
+
+    if (cbReqExpected == cbReq)
+    {
+        /* This is most likely a fixed size request, and in this case the request size
+         * must be also equal to the expected size.
+         */
+        if (pReq->size != cbReqExpected)
+        {
+            dprintf(("VbglGRVerify: request size %d != expected size %d\n", pReq->size, cbReqExpected));
+            return VERR_INVALID_PARAMETER;
+        }
+
+        return VINF_SUCCESS;
+    }
+
+    /* This can be a variable size request. Check the request type and limit the size
+     * to VMMDEV_MAX_VMMDEVREQ_SIZE, which is max size supported by the host. 
+     */
+    if (   pReq->requestType == VMMDevReq_LogString
+        || pReq->requestType == VMMDevReq_VideoSetVisibleRegion
+        || pReq->requestType == VMMDevReq_SetPointerShape
+#ifdef VBOX_WITH_64_BITS_GUESTS
+        || pReq->requestType == VMMDevReq_HGCMCall32
+        || pReq->requestType == VMMDevReq_HGCMCall64
+#else
+        || pReq->requestType == VMMDevReq_HGCMCall
+#endif /* VBOX_WITH_64_BITS_GUESTS */
+        || pReq->requestType == VMMDevReq_ChangeMemBalloon)
+    {
+        if (cbReq > VMMDEV_MAX_VMMDEVREQ_SIZE)
+        {
+            dprintf(("VbglGRVerify: VMMDevReq_LogString: buffer size %d too big\n", cbReq));
+            return VERR_BUFFER_OVERFLOW; /* @todo is this error code ok? */
+        }
+    }
+    else
+    {
+        dprintf(("VbglGRVerify: request size %d > buffer size %d\n", pReq->size, cbReq));
+        return VERR_IO_BAD_LENGTH; /* @todo is this error code ok? */
+    }
+
+    return VINF_SUCCESS;
+}
+
 DECLVBGL(int) VbglGRAlloc (VMMDevRequestHeader **ppReq, uint32_t cbSize, VMMDevRequestType reqType)
 {
     VMMDevRequestHeader *pReq;
Index: VirtualBox-2.0.6/src/VBox/Additions/linux/module/vboxmod.c
===================================================================
--- VirtualBox-2.0.6.orig/src/VBox/Additions/linux/module/vboxmod.c
+++ VirtualBox-2.0.6/src/VBox/Additions/linux/module/vboxmod.c
@@ -462,6 +462,21 @@ static int vboxadd_ioctl(struct inode *i
             }
             if (0 == rc)
             {
+                rc = VbglGRVerify(&reqHeader, cbRequestSize);
+                if (RT_FAILURE(rc))
+                {
+                    Log(("VBOXGUEST_IOCTL_VMMREQUEST: invalid request header: size %d min: %d type: %d rc: %d\n",
+                         cbRequestSize,
+                         cbVanillaRequestSize,
+                         reqHeader.requestType,
+                         rc));
+                    rc = -EINVAL;
+                }
+                else
+                    rc = 0;
+            }
+            if (0 == rc)
+            {
                 /* request storage for the full request */
                 rc = VbglGRAlloc(&reqFull, cbRequestSize, reqHeader.requestType);
                 if (VBOX_FAILURE(rc))