On Tue, 25 Oct 2022 18:07:13 +0200 Stefano Brivio <sbrivio(a)redhat.com> wrote:We need to zero out the checksum field before calculating the checksum, of course. I have no idea how this passed the "icmp" test set, looking into it.That's because the version of ping(8) I use on my test machine, from 'iputils', ignores a failed checksum in the reply: https://github.com/iputils/iputils/blob/59908434d7505ef574c2e0811ad1d5edb67… ...the parameter 'csfailed' in gather_statistics() is just passed as 0 here. The checksum was actually wrong in the CI test run. Forcing a specific version (e.g. from GNU inetutils) looks rather messy and non-portable, so I'm afraid there isn't much we can do for this, other than being careful. -- Stefano