4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Pablo Neira Ayuso <pablo@xxxxxxxxxxxxx> commit c9bd26513b3a11b3adb3c2ed8a31a01a87173ff1 upstream. nft -f -<<EOF add table ip t add table ip t { flags dormant; } add chain ip t c { type filter hook input priority 0; } add table ip t EOF Triggers a splat from nf core on next table delete because we lose track of right hook register state: WARNING: CPU: 2 PID: 1597 at net/netfilter/core.c:501 __nf_unregister_net_hook RIP: 0010:__nf_unregister_net_hook+0x41b/0x570 nf_unregister_net_hook+0xb4/0xf0 __nf_tables_unregister_hook+0x160/0x1d0 [..] The above should have table in *active* state, but in fact no hooks were registered. Reject on/off/on games rather than attempting to fix this. Fixes: 179d9ba5559a ("netfilter: nf_tables: fix table flag updates") Reported-by: "Lee, Cherie-Anne" <cherie.lee@xxxxxxxxxxx> Cc: Bing-Jhong Billy Jheng <billy@xxxxxxxxxxx> Cc: info@xxxxxxxxxxx Signed-off-by: Florian Westphal <fw@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/netfilter/nf_tables_api.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/net/netfilter/nf_tables_api.c +++ b/net/netfilter/nf_tables_api.c @@ -893,6 +893,10 @@ static int nf_tables_updtable(struct nft if (flags == ctx->table->flags) return 0; + /* No dormant off/on/off/on games in single transaction */ + if (ctx->table->flags & __NFT_TABLE_F_UPDATE) + return -EINVAL; + trans = nft_trans_alloc(ctx, NFT_MSG_NEWTABLE, sizeof(struct nft_trans_table)); if (trans == NULL)