Skip setuid test if systemd doesn't support disabling RDRAND

setuid.c calls getgrnam which can call nss-systemd which uses random bytes via systemd's `random_bytes()`. This will use RDRAND if systemd is too old to support SYSTEMD_RDRAND=0.

CMakeLists.txt

@@ -1207,7 +1207,6 @@ set(BASIC_TESTS
  setgid
  setgroups
  setsid
- setuid
  shared_exec
  shared_monitor
  shared_offset
@@ -1475,6 +1474,7 @@ set(TESTS_WITH_PROGRAM
  seccomp_open
  seccomp_signals
  segfault
+ setuid
  shared_map
  shared_persistent_file
  signal_numbers

src/test/setuid.run

@@ -0,0 +1,4 @@
+source `dirname $0`/util.sh
+skip_if_old_systemd
+compare_test EXIT-SUCCESS
+

src/test/util.sh

@@ -231,6 +231,16 @@ function skip_if_no_syscall_buf {
  fi
 }
 
+# If the systemd version doesn't allow disabling RDRAND, skip the test,
+# because it might trigger systemd code.
+function skip_if_old_systemd {
+ systemd_version=`systemctl --version | head -n1 | cut -d' ' -f2`
+ if [[ $systemd_version != "" && $systemd_version < 247 ]]; then
+ echo "can't disable RDRAND for systemd, skipping test"
+ exit 0
+ fi
+}
+
 function skip_if_test_32_bit {
  if [[ "_32" == $bitness ]]; then
  echo NOTE: Skipping "'$TESTNAME'" because 32-bit test