diff options
| author | Florian Westphal <fw@strlen.de> | 2022-02-28 04:18:05 +0100 |
|---|---|---|
| committer | Pablo Neira Ayuso <pablo@netfilter.org> | 2022-02-28 22:34:04 +0100 |
| commit | 17a8f31bba7bac8cce4bd12bab50697da96e7710 (patch) | |
| tree | 0f4827fd50e30d1a2b296ff0a7b9a024843a2b31 | |
| parent | 56763f12b0f02706576a088e85ef856deacc98a0 (diff) | |
netfilter: egress: silence egress hook lockdep splats
Netfilter assumes its called with rcu_read_lock held, but in egress
hook case it may be called with BH readlock.
This triggers lockdep splat.
In order to avoid to change all rcu_dereference() to
rcu_dereference_check(..., rcu_read_lock_bh_held()), wrap nf_hook_slow
with read lock/unlock pair.
Reported-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
| -rw-r--r-- | include/linux/netfilter_netdev.h | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/include/linux/netfilter_netdev.h b/include/linux/netfilter_netdev.h index b4dd96e4dc8d..e6487a691136 100644 --- a/include/linux/netfilter_netdev.h +++ b/include/linux/netfilter_netdev.h @@ -101,7 +101,11 @@ static inline struct sk_buff *nf_hook_egress(struct sk_buff *skb, int *rc, nf_hook_state_init(&state, NF_NETDEV_EGRESS, NFPROTO_NETDEV, dev, NULL, NULL, dev_net(dev), NULL); + + /* nf assumes rcu_read_lock, not just read_lock_bh */ + rcu_read_lock(); ret = nf_hook_slow(skb, &state, e, 0); + rcu_read_unlock(); if (ret == 1) { return skb; |