KernelSecurityTest.test_360_stacksignal_memleak fails

[Bethany Jamison]

For s2024.02.04 Bionic:linux-gcp-5.4 on instance n2d-standard-64 (suite ubuntu_qrt_kernel_security) test case KernelSecurityTest.test_360_stacksignal_memleak fails with "Kernel memory does not leak to userspace in signalstack (CVE-2009-2847)"

  test_360_stacksignal_memleak (__main__.KernelSecurityTest)
  Kernel memory does not leak to userspace in signalstack (CVE-2009-2847) ... FAIL

  ======================================================================
  FAIL: test_360_stacksignal_memleak (__main__.KernelSecurityTest)
  Kernel memory does not leak to userspace in signalstack (CVE-2009-2847)
  ----------------------------------------------------------------------
  Traceback (most recent call last):
    File "./test-kernel-security.py", line 2148, in test_360_stacksignal_memleak
      self.assertShellExitEquals(expected, self._unpriv_cmd(["./signal-stack"]))
    File "/home/ubuntu/autotest/client/tmp/ubuntu_qrt_kernel_security/src/qa-regression-testing/scripts/testlib.py", line 1321, in assertShellExitEquals
      self.assertEqual(expected, rc, msg + result + report)
  AssertionError: Got exit code -11, expected 0
  Command: 'sudo', '-u', 'ubuntu', './signal-stack'
  Output:
  [+] Checking platform...
  [+] sizeof(stack_t) = 24
  [+] Correct size, 64-bit platform.
  [+] Checking for stack_t hole...
  [+] ss_flags end (12) != ss_size start (16)
  [+] Hole in stack_t present!
  [+] Ready to call sigaltstack.

  ----------------------------------------------------------------------
  Ran 1 test in 0.096s

  FAILED (failures=1)
16:25:18 INFO | END ERROR ubuntu_qrt_kernel_security.KernelSecurityTest.test_360_stacksignal_memleak

This particular test case has not failed on any previous cycles for Bionic:linux-gcp-5.4, but the failure is the same between run #1 and #2 of the test. A 3rd run is in progress, and if the results are any different I will link them here.

I have attached the full console output to this bug as well.

[Bethany Jamison (bjamison)]

The 3rd run passed -- so maybe this test is more flaky than outright broken.