I think the issue is the CUDA driver version. It looks like the installer tries to install the newest version 455.23.05 and the installation actually fails there.
I've solved it by first downloading the local installer and unselecting the CUDA driver installation, so it just installs the toolkit.
chmod +x cuda_11.1.0_455.23.05_linux.run
In the menu unselect the driver installation:
If not already done, add the nvidia repo as per instructions from the official website before installing the driver:
sudo mv cuda-ubuntu1804.pin /etc/apt/preferences.d/cuda-repository-pin-600
sudo apt-key adv --fetch-keys https://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64/7fa2af80.pub
sudo add-apt-repository "deb https://developer.download.nvidia.com/compute/cuda/repos/ubuntu1804/x86_64/ /"
sudo apt-get update
Install the CUDA driver 450 manually:
sudo apt-get install cuda-drivers-450
Test by running
In case nvcc is not found, don't forget to add it to your PATH: