Fix tests using user namespaces on kernels that don't have it

Disable various tests if the kernel doesn't support unprivileged user
namespaces (e.g. Arch Linux disables them) or disable them via a sysctl
(Debian, Ubuntu).

Fixes #1521
Fixes #1625

1 files changed, 18 insertions, 0 deletions

diff --git a/tests/common.sh.in b/tests/common.sh.in
index 83643d8b06bb..186f9d6b9553 100644
--- a/tests/common.sh.in
+++ b/tests/common.sh.in
@@ -87,6 +87,24 @@ killDaemon() {
     trap "" EXIT
 }
 
+canUseSandbox() {
+    if [[ $(uname) != Linux ]]; then return 1; fi
+
+    if [ ! -L /proc/self/ns/user ]; then
+        echo "Kernel doesn't support user namespaces, skipping this test..."
+        return 1
+    fi
+
+    if [ -e /proc/sys/kernel/unprivileged_userns_clone ]; then
+        if [ "$(cat /proc/sys/kernel/unprivileged_userns_clone)" != 1 ]; then
+            echo "Unprivileged user namespaces disabled by sysctl, skipping this test..."
+            return 1
+        fi
+    fi
+
+    return 0
+}
+
 fail() {
     echo "$1"
     exit 1