On Thu, Jul 18, 2019 at 08:10:34PM +0200, Pablo Neira Ayuso wrote: > On Thu, Jul 18, 2019 at 05:37:29AM +0200, Phil Sutter wrote: > > nft_meta_get_eval()'s tendency to bail out setting NFT_BREAK verdict in > > situations where required data is missing breaks inverted checks > > like e.g.: > > > > | meta iifname != eth0 accept > > > > This rule will never match if there is no input interface (or it is not > > known) which is not intuitive and, what's worse, breaks consistency of > > iptables-nft with iptables-legacy. > > > > Fix this by falling back to placing a value in dreg which never matches > > (avoiding accidental matches): > > > > {I,O}IF: > > Use invalid ifindex value zero. > > > > {I,O}IFNAME, {I,O}IFKIND: > > Use an empty string which is neither a valid interface name nor > > kind. > > > > {I,O}IFTYPE: > > Use ARPHRD_VOID (0xFFFF). > > > > Signed-off-by: Phil Sutter <phil@xxxxxx> > > --- > > net/netfilter/nft_meta.c | 45 +++++++++++++++++----------------------- > > Missing update for: > > net/bridge/netfilter/nft_meta_bridge.c While you update this, would you also disentangle the default: case? default: goto out; ... out: return nft_meta_get_eval(expr, regs, pkt); not good to use goto like that. I'd suggest: default: nft_meta_get_eval(expr, regs, pkt); return; Thanks.