diff options
author | Florian Westphal | 2023-08-08 20:40:17 +0200 |
---|---|---|
committer | Florian Westphal | 2023-08-16 00:05:14 +0200 |
commit | b9f052dc68f69dac89fe1e24693354c033daa091 (patch) | |
tree | d3e3ae153f5057194ef409db697977b8a2e156a8 /net | |
parent | e4dd0d3a2f64b8bd8029ec70f52bdbebd0644408 (diff) |
netfilter: nf_tables: fix false-positive lockdep splat
->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>
Diffstat (limited to 'net')
-rw-r--r-- | net/netfilter/nft_set_pipapo.c | 13 |
1 files changed, 12 insertions, 1 deletions
diff --git a/net/netfilter/nft_set_pipapo.c b/net/netfilter/nft_set_pipapo.c index a5b8301afe4a..5fa12cfc7b84 100644 --- a/net/netfilter/nft_set_pipapo.c +++ b/net/netfilter/nft_set_pipapo.c @@ -1697,6 +1697,17 @@ 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); @@ -1705,7 +1716,7 @@ 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)) |