Re: Regression: Commit "netfilter: nf_tables: disallow rule addition to bound chain via NFTA_RULE_CHAIN_ID" breaks ruleset loading in linux-stable

[Timo Sigurdsson]

Hi,

Florian Westphal schrieb am 12.09.2023 12:27 (GMT +02:00):

> Linux regression tracking (Thorsten Leemhuis) <regressions@xxxxxxxxxxxxx>
> wrote:
>> On 12.09.23 00:57, Pablo Neira Ayuso wrote:
>> > Userspace nftables v1.0.6 generates incorrect bytecode that hits a new
>> > kernel check that rejects adding rules to bound chains. The incorrect
>> > bytecode adds the chain binding, attach it to the rule and it adds the
>> > rules to the chain binding. I have cherry-picked these three patches
>> > for nftables v1.0.6 userspace and your ruleset restores fine.
>> > [...]
>> 
>> Hmmmm. Well, this sounds like a kernel regression to me that normally
>> should be dealt with on the kernel level, as users after updating the
>> kernel should never have to update any userspace stuff to continue what
>> they have been doing before the kernel update.
> 
> This is a combo of a userspace bug and this new sanity check that
> rejects the incorrect ordering (adding rules to the already-bound
> anonymous chain).
> 

Out of curiosity, did the incorrect ordering or bytecode from the older userspace components actually lead to a wrong representation of the rules in the kernel or did the rules still work despite all that?

Thanks,

Timo