Re: [PATCH] [net-next] netfilter: bridge: make NF_TABLES_BRIDGE tristate

[Arnd Bergmann]

On Fri, Jul 19, 2019 at 8:37 AM Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> wrote:
>
> On Thu, Jul 18, 2019 at 09:01:10PM +0200, Pablo Neira Ayuso wrote:
> > On Wed, Jul 10, 2019 at 10:08:20AM +0200, Arnd Bergmann wrote:
> > > The new nft_meta_bridge code fails to link as built-in when NF_TABLES
> > > is a loadable module.
> > >
> > > net/bridge/netfilter/nft_meta_bridge.o: In function `nft_meta_bridge_get_eval':
> > > nft_meta_bridge.c:(.text+0x1e8): undefined reference to `nft_meta_get_eval'
> > > net/bridge/netfilter/nft_meta_bridge.o: In function `nft_meta_bridge_get_init':
> > > nft_meta_bridge.c:(.text+0x468): undefined reference to `nft_meta_get_init'
> > > nft_meta_bridge.c:(.text+0x49c): undefined reference to `nft_parse_register'
> > > nft_meta_bridge.c:(.text+0x4cc): undefined reference to `nft_validate_register_store'
> > > net/bridge/netfilter/nft_meta_bridge.o: In function `nft_meta_bridge_module_exit':
> > > nft_meta_bridge.c:(.exit.text+0x14): undefined reference to `nft_unregister_expr'
> > > net/bridge/netfilter/nft_meta_bridge.o: In function `nft_meta_bridge_module_init':
> > > nft_meta_bridge.c:(.init.text+0x14): undefined reference to `nft_register_expr'
> > > net/bridge/netfilter/nft_meta_bridge.o:(.rodata+0x60): undefined reference to `nft_meta_get_dump'
> > > net/bridge/netfilter/nft_meta_bridge.o:(.rodata+0x88): undefined reference to `nft_meta_set_eval'
> > >
> > > This can happen because the NF_TABLES_BRIDGE dependency itself is just a
> > > 'bool'.  Make the symbol a 'tristate' instead so Kconfig can propagate the
> > > dependencies correctly.
> >
> > Hm. Something breaks here. Investigating. Looks like bridge support is
> > gone after this, nft fails to register the filter chain type:
> >
> > # nft add table bridge x
> > # nft add chain bridge x y { type filter hook input priority 0\; }
> > Error: Could not process rule: No such file or directory
>
> Found it. It seems this patch is needed, on top of your patch.

Right, makes sense.

> I can just squash this chunk into your original patch and push it out
> if you're OK witht this.

Yes, please do.

      Arnd