Return-path: Received: from mail-io0-f193.google.com ([209.85.223.193]:36540 "EHLO mail-io0-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751099AbcFUW0x (ORCPT ); Tue, 21 Jun 2016 18:26:53 -0400 Received: by mail-io0-f193.google.com with SMTP id s63so4411406ioi.3 for ; Tue, 21 Jun 2016 15:26:04 -0700 (PDT) Date: Tue, 21 Jun 2016 18:26:02 -0400 From: Bob Copeland To: Johannes Berg Cc: Jouni Malinen , linux-wireless@vger.kernel.org Subject: Re: [PATCH] mac80211: Fix mesh estab_plinks counting in STA removal case Message-ID: <20160621222602.GA7271@localhost> (sfid-20160622_002734_350605_41303BB8) References: <20160619205102.GA28350@w1.fi> <1466536150.18972.1.camel@sipsolutions.net> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 In-Reply-To: <1466536150.18972.1.camel@sipsolutions.net> Sender: linux-wireless-owner@vger.kernel.org List-ID: On Tue, Jun 21, 2016 at 09:09:10PM +0200, Johannes Berg wrote: > > > ? ?*/ > > - changed = mesh_accept_plinks_update(sdata); > > + if (sdata->u.mesh.user_mpm && > > + ????sta->mesh->plink_state == NL80211_PLINK_ESTAB) > > + changed |= mesh_plink_dec_estab_count(sdata); > > + changed |= mesh_accept_plinks_update(sdata); > > ? if (!sdata->u.mesh.user_mpm) { > > ? changed |= mesh_plink_deactivate(sta); > > ? del_timer_sync(&sta->mesh->plink_timer); > > > > Does it have to be done before the mesh_accept_plinks_update()? > > If not, you should put it with the existing u.mesh.user_mpm check. If > yes, then the code is further buggy since only mesh_plink_deactivate() > will call it when the kernel MPM is used. Looks further buggy, so perhaps this untested patch would work, i.e. move the accepting-plinks change closer to the decrement, and push the user_mpm check down into mesh_plink_deactivate to just avoid sending the peering frames. [There's also a bit there for power saving that we likely want to keep for secure networks.] Then again maybe accepting_plinks flag should just be computed when used instead of tracking the state separately. --- net/mac80211/mesh.c | 18 ++---------------- net/mac80211/mesh_plink.c | 16 ++++++++++++---- 2 files changed, 14 insertions(+), 20 deletions(-) diff --git a/net/mac80211/mesh.c b/net/mac80211/mesh.c index 21b1fdf..3c150f8 100644 --- a/net/mac80211/mesh.c +++ b/net/mac80211/mesh.c @@ -148,22 +148,8 @@ u32 mesh_accept_plinks_update(struct ieee80211_sub_if_data *sdata) void mesh_sta_cleanup(struct sta_info *sta) { struct ieee80211_sub_if_data *sdata = sta->sdata; - u32 changed; - - /* - * maybe userspace handles peer allocation and peering, but in either - * case the beacon is still generated by the kernel and we might need - * an update. - */ - changed = mesh_accept_plinks_update(sdata); - if (!sdata->u.mesh.user_mpm) { - changed |= mesh_plink_deactivate(sta); - del_timer_sync(&sta->mesh->plink_timer); - } - - /* make sure no readers can access nexthop sta from here on */ - mesh_path_flush_by_nexthop(sta); - synchronize_net(); + u32 changed = mesh_plink_deactivate(sta); + del_timer_sync(&sta->mesh->plink_timer); if (changed) ieee80211_mbss_info_change_notify(sdata, changed); diff --git a/net/mac80211/mesh_plink.c b/net/mac80211/mesh_plink.c index 79f2a0a..69ac7a8 100644 --- a/net/mac80211/mesh_plink.c +++ b/net/mac80211/mesh_plink.c @@ -349,6 +349,8 @@ static u32 __mesh_plink_deactivate(struct sta_info *sta) changed = mesh_plink_dec_estab_count(sdata); sta->mesh->plink_state = NL80211_PLINK_BLOCKED; + changed |= mesh_accept_plinks_update(sdata); + ieee80211_mps_sta_status_update(sta); changed |= ieee80211_mps_set_sta_local_pm(sta, NL80211_MESH_POWER_UNKNOWN); @@ -370,13 +372,19 @@ u32 mesh_plink_deactivate(struct sta_info *sta) spin_lock_bh(&sta->mesh->plink_lock); changed = __mesh_plink_deactivate(sta); - sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED; - mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE, - sta->sta.addr, sta->mesh->llid, sta->mesh->plid, - sta->mesh->reason); + + if (sdata->u.mesh.user_mpm) { + sta->mesh->reason = WLAN_REASON_MESH_PEER_CANCELED; + mesh_plink_frame_tx(sdata, sta, WLAN_SP_MESH_PEERING_CLOSE, + sta->sta.addr, sta->mesh->llid, sta->mesh->plid, + sta->mesh->reason); + } spin_unlock_bh(&sta->mesh->plink_lock); mesh_path_flush_by_nexthop(sta); + /* make sure no readers can access nexthop sta from here on */ + synchronize_net(); + return changed; } -- 2.9.0