On Tue, Mar 15, 2022 at 09:48:52AM +0100, Hans Schultz wrote: > On mån, mar 14, 2022 at 17:30, Ido Schimmel <idosch@xxxxxxxxxx> wrote: > > On Thu, Mar 10, 2022 at 03:23:18PM +0100, Hans Schultz wrote: > >> @@ -94,8 +95,16 @@ int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb > >> br_fdb_find_rcu(br, eth_hdr(skb)->h_source, vid); > >> > >> if (!fdb_src || READ_ONCE(fdb_src->dst) != p || > >> - test_bit(BR_FDB_LOCAL, &fdb_src->flags)) > >> + test_bit(BR_FDB_LOCAL, &fdb_src->flags)) { > >> + if (!fdb_src) { > >> + set_bit(BR_FDB_ENTRY_LOCKED, &flags); > > > > This flag is read-only for user space, right? That is, the kernel needs > > to reject it during netlink policy validation. > > > > Yes, the flag is only readable from user space, unless there is a wish > to change that. OK, so please spell it out in the commit message so that it is clear the flag can only be set by the kernel.