Hi, This was an interesting little bug to invstigate. Here's what was happening. The test checks to see that when kptr_restrict == 1, the sock addresses reported in /proc/net/tcp are all zero for non-root users. It then sets kptr_restrict == 0 and attempts to verify that real pointers are reported to root and non-root users. However, recently the kernel started to hash these pointers instead, returning the hash value in it's place, *and* (the source of this bug) if insufficient entropy had been collected by the kernel up to this point, making the hash "weak", the values "(ptrval)" and "(____ptrval____)" would be returned instead. The QRT script assumed that whatever it read would at least be a hex number of some kind captured in a string and attempt to convert it to an int.
The insufficient entropy bit is why you would only see this failure on the first run of the test. This has been addressed in qrt commit https://git.launchpad.net/qa- regression-testing/commit/?id=46f217b3f9aa0e53bb18bd2049f934199870ed1c . Reference on the source of the values and insufficient entropy: https://www.kernel.org/doc/Documentation/core-api/printk-formats.rst (section on Plain Pointers) ** Changed in: qa-regression-testing Status: New => Fix Released ** Changed in: linux-kvm (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux-kvm in Ubuntu. https://bugs.launchpad.net/bugs/1831873 Title: test_095_kernel_symbols_missing_proc_net_tcp from ubuntu_qrt_kernel_security failed on B/C KVM Status in QA Regression Testing: Fix Released Status in ubuntu-kernel-tests: New Status in linux-kvm package in Ubuntu: Invalid Bug description: This issue can only be reproduced on the first run. The second run it will pass. ERROR: test_095_kernel_symbols_missing_proc_net_tcp (__main__.KernelSecurityTest) kernel addresses in /proc/net/tcp are zeroed out ---------------------------------------------------------------------- Traceback (most recent call last): File "./test-kernel-security.py", line 1392, in test_095_kernel_symbols_missing_proc_net_tcp self._check_pK_files(self. _095_kernel_symbols_missing_proc_net_tcp) File "./test-kernel-security.py", line 1235, in _check_pK_files test_function(expected_unrestricted) File "./test-kernel-security.py", line 1350, in _095_kernel_symbols_missing_proc_net_tcp expected) File "./test-kernel-security.py", line 1153, in _read_twice self.assertFalse(0 == int(address, 16), "%s: root saw %s - contents:\n%s" % (filename, address, root)) ValueError: invalid literal for int() with base 16: '(ptrval)' ProblemType: Bug DistroRelease: Ubuntu 18.10 Package: linux-image-4.18.0-1013-kvm 4.18.0-1013.13 ProcVersionSignature: User Name 4.18.0-1013.13-kvm 4.18.20 Uname: Linux 4.18.0-1013-kvm x86_64 ApportVersion: 2.20.10-0ubuntu13.3 Architecture: amd64 Date: Thu Jun 6 09:25:10 2019 SourcePackage: linux-kvm UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/qa-regression-testing/+bug/1831873/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp
