VMCI: integer overflow in vmci_datagram_dispatch()

This is untrusted user data from vmci_host_do_send_datagram() so the
VMCI_DG_SIZE() macro can have an integer overflow.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 2 insertions, 1 deletions

diff --git a/drivers/misc/vmw_vmci/vmci_datagram.c b/drivers/misc/vmw_vmci/vmci_datagram.c
index f3cdd904fe4d..822665245588 100644
--- a/drivers/misc/vmw_vmci/vmci_datagram.c
+++ b/drivers/misc/vmw_vmci/vmci_datagram.c
@@ -328,7 +328,8 @@ int vmci_datagram_dispatch(u32 context_id,
 
         BUILD_BUG_ON(sizeof(struct vmci_datagram) != 24);
 
-        if (VMCI_DG_SIZE(dg) > VMCI_MAX_DG_SIZE) {
+        if (dg->payload_size > VMCI_MAX_DG_SIZE ||
+            VMCI_DG_SIZE(dg) > VMCI_MAX_DG_SIZE) {
                 pr_devel("Payload (size=%llu bytes) too big to send\n",
                          (unsigned long long)dg->payload_size);
                 return VMCI_ERROR_INVALID_ARGS;