[release-1.26] "FATA [0000] permission denied" when /var is mounted noexec

[brandond]

• Backport "FATA [0000] permission denied" when /var is mounted noexec #7372

[fmoral2]

Validated on Version:

- k3s version v1.26.5+k3s-ad41fb8c -commit id = 8312c171b203c67256e8a0feae2d5036ee64e1b6

Environment Details

Infrastructure
Cloud EC2 instance

Node(s) CPU architecture, OS, and Version:
PRETTY_NAME="SUSE Linux Enterprise Server 15 SP4"

Cluster Configuration:
1 node

Config.yaml:

cat /etc/rancher/k3s/config,yaml
write-kubeconfig-mode: 644
token: test

Steps to validate the fix

1. Add a tmpfs mount to /var in fstab with noexec
2. reboot server
3. Try to install k3s server
4. Check the logs for the new error msg

Validation Results:

###########    Issue     ###########


v1.24.13+k3s-280e058f (280e058f)


~$ k3s --version

k3s version v1.26.5+k3s1

$ sudo vi /etc/fstab
tmpfs                   /var                tmpfs   defaults,nodev,nosuid,noexec        0 0

$ sudo reboot


$ curl https://get.k3s.io | INSTALL_K3S_COMMIT=8312c171b203c67256e8a0feae2d5036ee64e1b6  sh -s - server --cluster-init --token secret --prefer-bundled-bin --write-kubeconfig-mode=644

time="2023-05-15T20:28:23Z" level=fatal msg="exec /var/lib/rancher/k3s/data/3a5a046ca7504505788f8ab75ca8189219b088c6700b1e19a7aa5e755eb5bde9/bin/k3s-server failed: permission denied"