From patchwork Thu Jun 20 13:21:57 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sebastian Andrzej Siewior X-Patchwork-Id: 13705508 X-Patchwork-Delegate: kuba@kernel.org Received: from galois.linutronix.de (Galois.linutronix.de [193.142.43.55]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id AC93A1AE091; Thu, 20 Jun 2024 13:27:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=193.142.43.55 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718890057; cv=none; b=ImPNTBePnMbW9HJS/n7WZGtl+ciZnmD8yIO9w95bPx8Q/lIDpf3OhiRgdh+weRiUNesFXrqWwZXrZ+Azm0F2bos8T7AW4dxQw575FXj/g/o1zbtFi+wbQhAtIHcSMVmYJI3ouup7iz0ia5UorWzgS7+2CONKkHVxwruKodDF/BE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718890057; c=relaxed/simple; bh=hVYiIFL5HwJaYF05A9M5SqbFcZHu2+UJJv8+B5zsSCs=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=s6dKZt+1+c9NOxdmsJh5EEyc/q0iiEJhO5uA/puM5HQm0yLKD7ehra9WvxsKdLuN5GdE5xVzWZZgHw2waq6nUeBwZ88IR4Hyhl7gaYCcKqO3mRkyx/C+iiV4YK4MU4xlhAKBtA8s8H/ZEjikA2nEW7vr99olME0NeEaZ6/588hk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de; spf=pass smtp.mailfrom=linutronix.de; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=bxANh1gS; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b=uVtEEhpC; arc=none smtp.client-ip=193.142.43.55 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linutronix.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linutronix.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="bxANh1gS"; dkim=permerror (0-bit key) header.d=linutronix.de header.i=@linutronix.de header.b="uVtEEhpC" From: Sebastian Andrzej Siewior DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020; t=1718890053; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7Fimo9A+L9/O8JEt6UHonD1Uw2oHXu2TNi4Wzvh1cs4=; b=bxANh1gSjfTkjb1of2CTKsIDUvOSDJAUbHfCfy/FvFyth92S9dfVSoH+WCSmTuXjWvzwxt DACjKXQQ1VYIUIQsnFbUyv6Bv02RdibulAhl5hLFmhtPoWpuNMHDbM3PY6SEOLQCzu3BdP wcmeopCIlOo7aABqL85HqI1wXNxgFCEXQO4ydrz6oQea4aN8v0kTayekSBejrLDh32NKR2 0kMU3y7jT7N5LYd4y+g//zA4MQLR1IN7pVprYh7uo6uiVY3wYQjOIcE+A8Ct4sXoGIfKIw max+JfgnHByESacJAxA4OPs+jTBItb+RxU4q/fjG18Wftp4Y/m5tnaKLiEGgMw== DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=linutronix.de; s=2020e; t=1718890053; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=7Fimo9A+L9/O8JEt6UHonD1Uw2oHXu2TNi4Wzvh1cs4=; b=uVtEEhpCVzejJ054Aym774dUIX5mpnUiN6B9bHxjzorpiAOft8TrsEotoN0TfIIq5ejLnp XLqSEigg6nf9VIBw== To: linux-kernel@vger.kernel.org, netdev@vger.kernel.org Cc: "David S. Miller" , Daniel Bristot de Oliveira , Boqun Feng , Daniel Borkmann , Eric Dumazet , Frederic Weisbecker , Ingo Molnar , Jakub Kicinski , Paolo Abeni , Peter Zijlstra , Thomas Gleixner , Waiman Long , Will Deacon , Sebastian Andrzej Siewior , Florian Westphal , Jozsef Kadlecsik , Nikolay Aleksandrov , Pablo Neira Ayuso , Roopa Prabhu , bridge@lists.linux.dev, coreteam@netfilter.org, netfilter-devel@vger.kernel.org Subject: [PATCH v9 net-next 07/15] netfilter: br_netfilter: Use nested-BH locking for brnf_frag_data_storage. Date: Thu, 20 Jun 2024 15:21:57 +0200 Message-ID: <20240620132727.660738-8-bigeasy@linutronix.de> In-Reply-To: <20240620132727.660738-1-bigeasy@linutronix.de> References: <20240620132727.660738-1-bigeasy@linutronix.de> Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Patchwork-Delegate: kuba@kernel.org brnf_frag_data_storage is a per-CPU variable and relies on disabled BH for its locking. Without per-CPU locking in local_bh_disable() on PREEMPT_RT this data structure requires explicit locking. Add a local_lock_t to the data structure and use local_lock_nested_bh() for locking. This change adds only lockdep coverage and does not alter the functional behaviour for !PREEMPT_RT. Cc: Florian Westphal Cc: Jozsef Kadlecsik Cc: Nikolay Aleksandrov Cc: Pablo Neira Ayuso Cc: Roopa Prabhu Cc: bridge@lists.linux.dev Cc: coreteam@netfilter.org Cc: netfilter-devel@vger.kernel.org Signed-off-by: Sebastian Andrzej Siewior --- net/bridge/br_netfilter_hooks.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/net/bridge/br_netfilter_hooks.c b/net/bridge/br_netfilter_hooks.c index bf30c50b56895..3c9f6538990ea 100644 --- a/net/bridge/br_netfilter_hooks.c +++ b/net/bridge/br_netfilter_hooks.c @@ -137,6 +137,7 @@ static inline bool is_pppoe_ipv6(const struct sk_buff *skb, #define NF_BRIDGE_MAX_MAC_HEADER_LENGTH (PPPOE_SES_HLEN + ETH_HLEN) struct brnf_frag_data { + local_lock_t bh_lock; char mac[NF_BRIDGE_MAX_MAC_HEADER_LENGTH]; u8 encap_size; u8 size; @@ -144,7 +145,9 @@ struct brnf_frag_data { __be16 vlan_proto; }; -static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage); +static DEFINE_PER_CPU(struct brnf_frag_data, brnf_frag_data_storage) = { + .bh_lock = INIT_LOCAL_LOCK(bh_lock), +}; static void nf_bridge_info_free(struct sk_buff *skb) { @@ -850,6 +853,7 @@ static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff { struct nf_bridge_info *nf_bridge = nf_bridge_info_get(skb); unsigned int mtu, mtu_reserved; + int ret; mtu_reserved = nf_bridge_mtu_reduction(skb); mtu = skb->dev->mtu; @@ -882,6 +886,7 @@ static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff IPCB(skb)->frag_max_size = nf_bridge->frag_max_size; + local_lock_nested_bh(&brnf_frag_data_storage.bh_lock); data = this_cpu_ptr(&brnf_frag_data_storage); if (skb_vlan_tag_present(skb)) { @@ -897,7 +902,9 @@ static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff skb_copy_from_linear_data_offset(skb, -data->size, data->mac, data->size); - return br_nf_ip_fragment(net, sk, skb, br_nf_push_frag_xmit); + ret = br_nf_ip_fragment(net, sk, skb, br_nf_push_frag_xmit); + local_unlock_nested_bh(&brnf_frag_data_storage.bh_lock); + return ret; } if (IS_ENABLED(CONFIG_NF_DEFRAG_IPV6) && skb->protocol == htons(ETH_P_IPV6)) { @@ -909,6 +916,7 @@ static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff IP6CB(skb)->frag_max_size = nf_bridge->frag_max_size; + local_lock_nested_bh(&brnf_frag_data_storage.bh_lock); data = this_cpu_ptr(&brnf_frag_data_storage); data->encap_size = nf_bridge_encap_header_len(skb); data->size = ETH_HLEN + data->encap_size; @@ -916,8 +924,12 @@ static int br_nf_dev_queue_xmit(struct net *net, struct sock *sk, struct sk_buff skb_copy_from_linear_data_offset(skb, -data->size, data->mac, data->size); - if (v6ops) - return v6ops->fragment(net, sk, skb, br_nf_push_frag_xmit); + if (v6ops) { + ret = v6ops->fragment(net, sk, skb, br_nf_push_frag_xmit); + local_unlock_nested_bh(&brnf_frag_data_storage.bh_lock); + return ret; + } + local_unlock_nested_bh(&brnf_frag_data_storage.bh_lock); kfree_skb(skb); return -EMSGSIZE;