namespaceTest compares UTS namespace instead of time namespace for TimeNamespace case

[abhaygoudannavar]

Description

In tests/e2e/test_functions.go, the namespaceTest function has a copy-paste error in the specs.TimeNamespace switch case. It compares the UTS namespace (cntrNsMap["uts"]) instead of the time namespace, and reports the error as "uts:" instead of "time:".

This means time namespace isolation is never actually validated by the e2e test suite. The TimeNamespace case silently re-runs the exact same check as the UTSNamespace case above it, giving a false sense of test coverage.Additionally, the getProcNS() helper in tests/e2e/utils.go does not read the time_for_children symlink from /proc//ns/, so the time namespace data is not even available for comparison.

Root Cause

In tests/e2e/test_functions.go, the TimeNamespace case is a direct copy-paste of the UTSNamespace case without updating the namespace key or error label:

// correct UTS case
case specs.UTSNamespace:
    err = compareNS(cntrNsMap["uts"], selfNsMap["uts"], ns.Path)
    if err != nil {
        return fmt.Errorf("uts: %w", err)
    }
// broken Time case (identical to UTS above)
case specs.TimeNamespace:
    err = compareNS(cntrNsMap["uts"], selfNsMap["uts"], ns.Path)  // ← should be "time_for_children"
    if err != nil {
        return fmt.Errorf("uts: %w", err)  // ← should be "time:"
    }

Furthermore, getProcNS() in tests/e2e/utils.go reads cgroup, ipc, mnt, net, pid, user, and uts — but never reads time_for_children:

// utils.go:155-196 — getProcNS() namespace list
ns["cgroup"] = ...
ns["ipc"]    = ...
ns["mnt"]    = ...
ns["net"]    = ...
ns["pid"]    = ...
ns["user"]   = ...
ns["uts"]    = ...
//  missing: ns["time_for_children"]

Proposed Fix

• Extend getProcNS() in utils.go to read the time namespace:

// Add after the "uts" readlink block (line ~193):
timePath := filepath.Join(procPath, "time_for_children")
ns["time_for_children"], err = os.Readlink(timePath)
if err != nil {
    return nil, err
}

• Fix the TimeNamespace case in test_functions.go:

case specs.TimeNamespace:
    err = compareNS(cntrNsMap["time_for_children"], selfNsMap["time_for_children"], ns.Path)
    if err != nil {
        return fmt.Errorf("time: %w", err)
    }

System info

• Repository: urunc_test
• Files affected:
  1.tests/e2e/test_functions.go, lines 312-316
  2.tests/e2e/utils.go, lines 155-196
• Arch: Any (bug is in test logic, not architecture-specific)
• VMM: Any (bug affects all VMMs that use time namespaces)
• Unikernel: Any (bug is in the test framework, not unikernel-specific)

Steps to reproduce

• Run the namespace e2e test (currently only defined for Firecracker-unikraft in nerdctl):

make test_nerdctl_namespaces

• The test passes — but it is falsely passing. To confirm it's a false positive, add a debug log inside the TimeNamespace case:

case specs.TimeNamespace:
    fmt.Printf("DEBUG: comparing uts=%s vs uts=%s (should be time!)\n",
        cntrNsMap["uts"], selfNsMap["uts"])

• Re-run the test and observe the debug output — it prints UTS namespace inode numbers, not time namespace inode numbers, confirming the wrong namespace is being compared.

• Expected behavior: The TimeNamespace case reads /proc//ns/time_for_children and compares the container's time namespace against the host's time namespace, validating that time namespace isolation is correctly applied.

• Actual behavior: The TimeNamespace case re-reads /proc//ns/uts (same as the UTSNamespace case above) and silently passes, providing zero coverage for time namespace isolation.