Dear SCTP developers, I have to get back to this bug. It is slowly turning into a nightmare. Not only affected it forwards/backwards compatibility of application binaries during upgrades of a distribution, but it also affects the ability to run containerized workloads with SCTP. It's sort-of obvious but I didn't realize it until now. We are observing this problem now when we operate CentOS 8 based containers on a Debian 9 based (docker) host. Apparently the CentOS userland has a different definition of the event structure (larger) than the Debian kernel has (smaller) -> boom. >From my point of view, this bug is making it virtually impossible to run containerized telecom workloads. I guess most users are very conservative and still running rather ancient kernels and/or distributions, but as soon as they start upgrading their kernel to anything that includes that patch to the SCTP events structure, the nightmare starts. To my knowledge, there is no infrastructure at all for a situation like this - neither in the Docker universe nor in k8s.. You cannot build separate container images depending on what the host OS/kernel is going to be. And particularly, if you are not self-hosting your container runtimes but running your containers on some kind of cloud infrastructure provider, you have no control over what exact kernel version might be in use there - and it also may change at any time at the discretion of the cloud service provider. On Fri, May 01, 2020 at 11:20:08AM -0300, Marcelo Ricardo Leitner wrote: > That's what we want as well. Some breakage happened, yes, by mistake, > and fixing that properly now, without breaking anything else, may be > just impossible, unfortunatelly. But you can be sure that we are > engaged on not doing it again. I would actually seriously consider to roll that change back - not only in the next kernel release but also in all stable kernel releases. At least the breakage then is constrained to a limited set of kernel versions. Alternatively, I suggest to at least apply a patch to all supported stable kernel series (picked up hopefully distributions) that makes those older kernels accept a larger-length sctp_event_subscribe structure from userspace, *if* any of the additional members are 0 (memcmp the difference between old and new). Regards, Harald -- - Harald Welte <laforge@xxxxxxxxxxxx> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)
