VMCI: use memdup_user().

Use memdup_user to duplicate a memory region from user-space to
kernel-space, instead of open coding using kmalloc & copy_from_user.

Signed-off-by: Muhammad Falak R Wani <falakreyaz@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/misc/vmw_vmci/vmci_host.c b/drivers/misc/vmw_vmci/vmci_host.c
index 9ec262a..ec09010 100644 (file)
--- a/drivers/misc/vmw_vmci/vmci_host.c
+++ b/drivers/misc/vmw_vmci/vmci_host.c
@@ -381,18 +381,12 @@ static int vmci_host_do_send_datagram(struct vmci_host_dev *vmci_host_dev,
                return -EINVAL;
        }
 
-       dg = kmalloc(send_info.len, GFP_KERNEL);
-       if (!dg) {
+       dg = memdup_user((void __user *)(uintptr_t)send_info.addr,
+                        send_info.len);
+       if (IS_ERR(dg)) {
                vmci_ioctl_err(
                        "cannot allocate memory to dispatch datagram\n");
-               return -ENOMEM;
-       }
-
-       if (copy_from_user(dg, (void __user *)(uintptr_t)send_info.addr,
-                          send_info.len)) {
-               vmci_ioctl_err("error getting datagram\n");
-               kfree(dg);
-               return -EFAULT;
+               return PTR_ERR(dg);
        }
 
        if (VMCI_DG_SIZE(dg) != send_info.len) {