From: Florian Westphal fw@strlen.de
[ Upstream commit b9f052dc68f69dac89fe1e24693354c033daa091 ]
->abort invocation may cause splat on debug kernels:
WARNING: suspicious RCU usage net/netfilter/nft_set_pipapo.c:1697 suspicious rcu_dereference_check() usage! [..] rcu_scheduler_active = 2, debug_locks = 1 1 lock held by nft/133554: [..] (nft_net->commit_mutex){+.+.}-{3:3}, at: nf_tables_valid_genid [..] lockdep_rcu_suspicious+0x1ad/0x260 nft_pipapo_abort+0x145/0x180 __nf_tables_abort+0x5359/0x63d0 nf_tables_abort+0x24/0x40 nfnetlink_rcv+0x1a0a/0x22c0 netlink_unicast+0x73c/0x900 netlink_sendmsg+0x7f0/0xc20 ____sys_sendmsg+0x48d/0x760
Transaction mutex is held, so parallel updates are not possible. Switch to _protected and check mutex is held for lockdep enabled builds.
Fixes: 212ed75dc5fb ("netfilter: nf_tables: integrate pipapo into commit protocol") Signed-off-by: Florian Westphal fw@strlen.de Signed-off-by: Sasha Levin sashal@kernel.org --- net/netfilter/nft_set_pipapo.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c index 92b108e3000eb..3b5c3919fff9c 100644 --- a/net/netfilter/nft_set_pipapo.c +++ b/net/netfilter/nft_set_pipapo.c @@ -1698,6 +1698,17 @@ static void nft_pipapo_commit(const struct nft_set *set) priv->clone = new_clone; }
+static bool nft_pipapo_transaction_mutex_held(const struct nft_set *set) +{ +#ifdef CONFIG_PROVE_LOCKING + const struct net *net = read_pnet(&set->net); + + return lockdep_is_held(&nft_pernet(net)->commit_mutex); +#else + return true; +#endif +} + static void nft_pipapo_abort(const struct nft_set *set) { struct nft_pipapo *priv = nft_set_priv(set); @@ -1706,7 +1717,7 @@ static void nft_pipapo_abort(const struct nft_set *set) if (!priv->dirty) return;
- m = rcu_dereference(priv->match); + m = rcu_dereference_protected(priv->match, nft_pipapo_transaction_mutex_held(set));
new_clone = pipapo_clone(m); if (IS_ERR(new_clone))