Re: [LTP] [PATCH v2] security/dirtyc0w_shmem: Add new test for CVE-2022-2590

David Hildenbrand
2022-11-25T10:40:58Z

On 25.11.22 11:39, Petr Vorel wrote:
> Hi Martin, David,
>
>> On 23. 11. 22 11:35, David Hildenbrand wrote:
>>> + uffdio_api.api = UFFD_API;
>>> + uffdio_api.features = UFFD_FEATURE_MINOR_SHMEM;
>>> + TEST(ioctl(uffd, UFFDIO_API, &uffdio_api));
>>> + if (TST_RET < 0) {
>
>> One more thing, checking just the ioctl() return value here is not enough.
>> You need to check that uffdio_api.features still includes the
>> UFFD_FEATURE_MINOR_SHMEM flag after the call. PPC64 does not seem to support
>> it on kernel 5.14 and the ioctl() still succeeds there.
> Very good catch, thanks!
>
> David, please send official patch (speedups merging). Thanks a lot!

Interesting, thanks for testing! Will fix that as well and send a
combined patch.

--
Thanks,

David / dhildenb