On Thu, Jun 22, 2017 at 10:49 AM, Andy Lutomirski <luto@xxxxxxxxxx> wrote: > On Thu, Jun 22, 2017 at 10:09 AM, Shuah Khan <shuah@xxxxxxxxxx> wrote: >> On 06/22/2017 10:53 AM, Kees Cook wrote: >>> On Thu, Jun 22, 2017 at 9:18 AM, Sumit Semwal <sumit.semwal@xxxxxxxxxx> wrote: >>>> Hi Kees, Andy, >>>> >>>> On 15 June 2017 at 23:26, Sumit Semwal <sumit.semwal@xxxxxxxxxx> wrote: >>>>> 3. 'seccomp ptrace hole closure' patches got added in 4.7 [3] - >>>>> feature and test together. >>>>> - This one also seems like a security hole being closed, and the >>>>> 'feature' could be a candidate for stable backports, but Arnd tried >>>>> that, and it was quite non-trivial. So perhaps we'll need some help >>>>> from the subsystem developers here. >>>> >>>> Could you please help us sort this out? Our goal is to help Greg with >>>> testing stable kernels, and currently the seccomp tests fail due to >>>> missing feature (seccomp ptrace hole closure) getting tested via >>>> latest kselftest. >>>> >>>> If you feel the feature isn't a stable candidate, then could you >>>> please help make the test degrade gracefully in its absence? >>> >>> I don't really want to have that change be a backport -- it's quite >>> invasive across multiple architectures. >>> >>> I would say just add a kernel version check to the test. This is >>> probably not the only selftest that will need such things. :) >> >> Adding release checks to selftests is going to problematic for maintenance. >> Tests should fail gracefully if feature isn't supported in older kernels. >> >> Several tests do that now and please find a way to check for dependencies >> and feature availability and fail the test gracefully. If there is a test >> that can't do that for some reason, we can discuss it, but as a general >> rule, I don't want to see kselftest patches that check release. > > If a future kernel inadvertently loses the new feature and degrades to > the behavior of old kernels, that would be a serious bug and should be > caught. Right. I really think stable kernels should be tested with their own selftests. If some test is needed in a stable kernel it should be backported to that stable kernel. -Kees -- Kees Cook Pixel Security -- To unsubscribe from this list: send the line "unsubscribe linux-kselftest" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
