Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 875F9C6FD1C for ; Tue, 14 Mar 2023 10:00:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229548AbjCNKAT (ORCPT ); Tue, 14 Mar 2023 06:00:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38690 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229854AbjCNKAM (ORCPT ); Tue, 14 Mar 2023 06:00:12 -0400 Received: from nbd.name (nbd.name [46.4.11.11]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D12D32A6C6 for ; Tue, 14 Mar 2023 03:00:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=nbd.name; s=20160729; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=fQ71MCosSQV5sl0EroSadaOUdZ8yNoZcNVt7RDex3J8=; b=os3X6sylGMFd01VRkj0xDi4XfO 9V+LTKtLdOI1GFyxEB8/etWDyxxHfZHN6Z79Ske6QPlC0Zf0kMfbts2vBCXojnunWfKVxrXxOr/af q7LGpLUfuK1F0bSQtreV852uoduYs2Kj/eljwWqHfRk2M7e0T2W5wDaVeVSrZD6rWgtQ=; Received: from p54ae9730.dip0.t-ipconnect.de ([84.174.151.48] helo=Maecks.lan) by ds12 with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 (Exim 4.94.2) (envelope-from ) id 1pc1Rn-001pV5-9j; Tue, 14 Mar 2023 10:59:59 +0100 From: Felix Fietkau To: linux-wireless@vger.kernel.org Cc: johannes@sipsolutions.net, Ryder Lee Subject: [PATCH 2/7] wifi: mac80211: fix race in mesh sequence number assignment Date: Tue, 14 Mar 2023 10:59:51 +0100 Message-Id: <20230314095956.62085-2-nbd@nbd.name> X-Mailer: git-send-email 2.39.0 In-Reply-To: <20230314095956.62085-1-nbd@nbd.name> References: <20230314095956.62085-1-nbd@nbd.name> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org Since the sequence number is shared across different tx queues, it needs to be atomic in order to avoid accidental duplicate assignment Signed-off-by: Felix Fietkau --- net/mac80211/ieee80211_i.h | 2 +- net/mac80211/mesh.c | 6 ++---- 2 files changed, 3 insertions(+), 5 deletions(-) diff --git a/net/mac80211/ieee80211_i.h b/net/mac80211/ieee80211_i.h index 3d4edc25a69e..a4e1fdab1d3d 100644 --- a/net/mac80211/ieee80211_i.h +++ b/net/mac80211/ieee80211_i.h @@ -696,7 +696,7 @@ struct ieee80211_if_mesh { struct mesh_stats mshstats; struct mesh_config mshcfg; atomic_t estab_plinks; - u32 mesh_seqnum; + atomic_t mesh_seqnum; bool accepting_plinks; int num_gates; struct beacon_data __rcu *beacon; diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index 5a99b8f6e465..0608ed415831 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -752,10 +752,8 @@ unsigned int ieee80211_new_mesh_header(struct ieee80211_sub_if_data *sdata, meshhdr->ttl = sdata->u.mesh.mshcfg.dot11MeshTTL; - /* FIXME: racy -- TX on multiple queues can be concurrent */ - put_unaligned(cpu_to_le32(sdata->u.mesh.mesh_seqnum), &meshhdr->seqnum); - sdata->u.mesh.mesh_seqnum++; - + put_unaligned_le32(atomic_inc_return(&sdata->u.mesh.mesh_seqnum), + &meshhdr->seqnum); if (addr4or5 && !addr6) { meshhdr->flags |= MESH_FLAGS_AE_A4; memcpy(meshhdr->eaddr1, addr4or5, ETH_ALEN); -- 2.39.0