Q:

Can't run any container with an entrypoint script

I work with docker on a daily basis, but this morning, when I tried to launch some containers, it failed for every of my containers with an entrypoint script: 
$ docker run postgres:11
bash: /usr/local/bin/docker-entrypoint.sh: Permission denied

$ docker run mysql:5
/bin/bash: /usr/local/bin/docker-entrypoint.sh: Permission denied

$ docker run php:7.3-apache
/bin/sh: 0: Can't open /usr/local/bin/docker-php-entrypoint

I managed to docker run hello-world without errors. 
What happens? I don't think I have changed anything important on my computer since the last time it worked... I am on Ubuntu 20.04. 
Thanks for your help.
UPDATE
I still don't know what was going on. I managed to make it work again by removing docker-ce and re-installing it: 
sudo apt-get remove docker-ce
sudo apt install docker-ce
docker run postgres:11
  ==> ok, worked!

But, each time I shut down my laptop and then turn it on, I have the same problem again, docker doesn't run any container with an entrypoint. 
Any ideas?

A:

Well, following the idea of @PieterBeyens, I checked apparmor, and indeed,it was denying me read access to /usr/local/bin/docker-entrypoint.sh. It also appeared that I had a mixed snap/apt installation of docker and docker-compose. It was a mess. 
So, for future readers, what I did and finally worked (you may need to adapt, but you have the general idea): 
# Remove the docker and docker-compose snaps
sudo snap remove docker-compose 
sudo snap remove docker
# Remove the packages via apt
sudo apt-get purge -y  docker-ce docker-ce-cli containerd.io
# Remove the apparmor profiles (snap ones for docker)
sudo aa-remove-unknown
# Reinstall via apt
sudo apt-get install docker-ce=5:19.03.8~3-0~ubuntu-bionic docker-ce-cli=5:19.03.8~3-0~ubuntu-bionic containerd.io

And I also resinstalled docker-compose via curl.  

