Re: [PATCH] misc: fastrpc: Fix double free of 'buf' in error path

[Dan Carpenter]

> ----------------------->cut<---------------------------
> diff --git a/drivers/misc/fastrpc.c b/drivers/misc/fastrpc.c
> index f60bbf99485c..3fdd326e1ae8 100644
> --- a/drivers/misc/fastrpc.c
> +++ b/drivers/misc/fastrpc.c
> @@ -1891,7 +1891,8 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl,
> char __user *argp)
>                                       &args[0]);
>         if (err) {
>                 dev_err(dev, "mmap error (len 0x%08llx)\n", buf->size);
> -               goto err_invoke;
> +               fastrpc_buf_free(buf);
> +               return err;
>         }
> 
>         /* update the buffer to be able to deallocate the memory on the DSP
> */
> @@ -1930,11 +1931,7 @@ static int fastrpc_req_mmap(struct fastrpc_user *fl,
> char __user *argp)
>         return 0;
> 
>  err_assign:
> -       fastrpc_req_munmap_impl(fl, buf);
> -err_invoke:
> -       fastrpc_buf_free(buf);
> -
> -       return err;
> +       return fastrpc_req_munmap_impl(fl, buf);

This will return success if copy_to_user() fails.

regards,
dan carpenter