From patchwork Wed May 12 14:49:18 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg Kroah-Hartman X-Patchwork-Id: 438454 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-19.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER, INCLUDES_PATCH, MAILING_LIST_MULTI, SPF_HELO_NONE, SPF_PASS, USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 07159C2B9FC for ; Wed, 12 May 2021 15:50:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id DEA7561DC4 for ; Wed, 12 May 2021 15:50:03 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237287AbhELPtl (ORCPT ); Wed, 12 May 2021 11:49:41 -0400 Received: from mail.kernel.org ([198.145.29.99]:41718 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234063AbhELPnM (ORCPT ); Wed, 12 May 2021 11:43:12 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 11411613DA; Wed, 12 May 2021 15:22:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1620832937; bh=QTTUFpROkm8dS7T8quIL5mVZnCVjcNUhbHG058qivy4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ULZ/BFyOC4sSQIbs77GLQcADouln7UN6JfsANUtkeE+BYzVmyT/kprzamTBiizTEe px7fZovelx9x8dnoB1qkAk/4ZtnkA0eDOIkx67IHeTq4VUEPU+CjB/iW4+MYZ4udOz unuPtFm1IznQ3Nhyz/dhbi89DXsV/Em9d3hCmorU= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Tanner Love , Willem de Bruijn , Eric Dumazet , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.10 448/530] net/packet: make packet_fanout.arr size configurable up to 64K Date: Wed, 12 May 2021 16:49:18 +0200 Message-Id: <20210512144834.492970328@linuxfoundation.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210512144819.664462530@linuxfoundation.org> References: <20210512144819.664462530@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Tanner Love [ Upstream commit 9c661b0b85444e426d3f23250305eeb16f6ffe88 ] One use case of PACKET_FANOUT is lockless reception with one socket per CPU. 256 is a practical limit on increasingly many machines. Increase PACKET_FANOUT_MAX to 64K. Expand setsockopt PACKET_FANOUT to take an extra argument max_num_members. Also explicitly define a fanout_args struct, instead of implicitly casting to an integer. This documents the API and simplifies the control flow. If max_num_members is not specified or is set to 0, then 256 is used, same as before. Signed-off-by: Tanner Love Signed-off-by: Willem de Bruijn Reviewed-by: Eric Dumazet Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- include/uapi/linux/if_packet.h | 12 +++++++++++ net/packet/af_packet.c | 37 +++++++++++++++++++++++----------- net/packet/internal.h | 5 +++-- 3 files changed, 40 insertions(+), 14 deletions(-) diff --git a/include/uapi/linux/if_packet.h b/include/uapi/linux/if_packet.h index 3d884d68eb30..c07caf7b40db 100644 --- a/include/uapi/linux/if_packet.h +++ b/include/uapi/linux/if_packet.h @@ -2,6 +2,7 @@ #ifndef __LINUX_IF_PACKET_H #define __LINUX_IF_PACKET_H +#include #include struct sockaddr_pkt { @@ -296,6 +297,17 @@ struct packet_mreq { unsigned char mr_address[8]; }; +struct fanout_args { +#if defined(__LITTLE_ENDIAN_BITFIELD) + __u16 id; + __u16 type_flags; +#else + __u16 type_flags; + __u16 id; +#endif + __u32 max_num_members; +}; + #define PACKET_MR_MULTICAST 0 #define PACKET_MR_PROMISC 1 #define PACKET_MR_ALLMULTI 2 diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index a0121e7c98b1..92501e5f9d49 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1636,13 +1636,15 @@ static bool fanout_find_new_id(struct sock *sk, u16 *new_id) return false; } -static int fanout_add(struct sock *sk, u16 id, u16 type_flags) +static int fanout_add(struct sock *sk, struct fanout_args *args) { struct packet_rollover *rollover = NULL; struct packet_sock *po = pkt_sk(sk); + u16 type_flags = args->type_flags; struct packet_fanout *f, *match; u8 type = type_flags & 0xff; u8 flags = type_flags >> 8; + u16 id = args->id; int err; switch (type) { @@ -1700,11 +1702,21 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) } } err = -EINVAL; - if (match && match->flags != flags) - goto out; - if (!match) { + if (match) { + if (match->flags != flags) + goto out; + if (args->max_num_members && + args->max_num_members != match->max_num_members) + goto out; + } else { + if (args->max_num_members > PACKET_FANOUT_MAX) + goto out; + if (!args->max_num_members) + /* legacy PACKET_FANOUT_MAX */ + args->max_num_members = 256; err = -ENOMEM; - match = kzalloc(sizeof(*match), GFP_KERNEL); + match = kvzalloc(struct_size(match, arr, args->max_num_members), + GFP_KERNEL); if (!match) goto out; write_pnet(&match->net, sock_net(sk)); @@ -1720,6 +1732,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.func = packet_rcv_fanout; match->prot_hook.af_packet_priv = match; match->prot_hook.id_match = match_fanout_group; + match->max_num_members = args->max_num_members; list_add(&match->list, &fanout_list); } err = -EINVAL; @@ -1730,7 +1743,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.type == po->prot_hook.type && match->prot_hook.dev == po->prot_hook.dev) { err = -ENOSPC; - if (refcount_read(&match->sk_ref) < PACKET_FANOUT_MAX) { + if (refcount_read(&match->sk_ref) < match->max_num_members) { __dev_remove_pack(&po->prot_hook); po->fanout = match; po->rollover = rollover; @@ -1744,7 +1757,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) if (err && !refcount_read(&match->sk_ref)) { list_del(&match->list); - kfree(match); + kvfree(match); } out: @@ -3075,7 +3088,7 @@ static int packet_release(struct socket *sock) kfree(po->rollover); if (f) { fanout_release_data(f); - kfree(f); + kvfree(f); } /* * Now the socket is dead. No more input will appear. @@ -3866,14 +3879,14 @@ packet_setsockopt(struct socket *sock, int level, int optname, sockptr_t optval, } case PACKET_FANOUT: { - int val; + struct fanout_args args = { 0 }; - if (optlen != sizeof(val)) + if (optlen != sizeof(int) && optlen != sizeof(args)) return -EINVAL; - if (copy_from_sockptr(&val, optval, sizeof(val))) + if (copy_from_sockptr(&args, optval, optlen)) return -EFAULT; - return fanout_add(sk, val & 0xffff, val >> 16); + return fanout_add(sk, &args); } case PACKET_FANOUT_DATA: { diff --git a/net/packet/internal.h b/net/packet/internal.h index fd41ecb7f605..baafc3f3fa25 100644 --- a/net/packet/internal.h +++ b/net/packet/internal.h @@ -77,11 +77,12 @@ struct packet_ring_buffer { }; extern struct mutex fanout_mutex; -#define PACKET_FANOUT_MAX 256 +#define PACKET_FANOUT_MAX (1 << 16) struct packet_fanout { possible_net_t net; unsigned int num_members; + u32 max_num_members; u16 id; u8 type; u8 flags; @@ -90,10 +91,10 @@ struct packet_fanout { struct bpf_prog __rcu *bpf_prog; }; struct list_head list; - struct sock *arr[PACKET_FANOUT_MAX]; spinlock_t lock; refcount_t sk_ref; struct packet_type prot_hook ____cacheline_aligned_in_smp; + struct sock *arr[]; }; struct packet_rollover {