From patchwork Sat Dec 15 09:03:02 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Coelho X-Patchwork-Id: 10732063 X-Patchwork-Delegate: johannes@sipsolutions.net Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CC30714E5 for ; Sat, 15 Dec 2018 09:03:43 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B7EAF1FFBD for ; Sat, 15 Dec 2018 09:03:43 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id AC4A729179; Sat, 15 Dec 2018 09:03:43 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 647A4290E2 for ; Sat, 15 Dec 2018 09:03:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729687AbeLOJDf (ORCPT ); Sat, 15 Dec 2018 04:03:35 -0500 Received: from paleale.coelho.fi ([176.9.41.70]:42184 "EHLO farmhouse.coelho.fi" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1726030AbeLOJDf (ORCPT ); Sat, 15 Dec 2018 04:03:35 -0500 Received: from 91-156-4-241.elisa-laajakaista.fi ([91.156.4.241] helo=redipa.ger.corp.intel.com) by farmhouse.coelho.fi with esmtpsa (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.91) (envelope-from ) id 1gY5r9-0002oc-NS; Sat, 15 Dec 2018 11:03:32 +0200 From: Luca Coelho To: johannes@sipsolutions.net Cc: linux-wireless@vger.kernel.org, Lior Cohen , Luca Coelho Date: Sat, 15 Dec 2018 11:03:02 +0200 Message-Id: <20181215090325.31604-2-luca@coelho.fi> X-Mailer: git-send-email 2.19.2 In-Reply-To: <20181215090325.31604-1-luca@coelho.fi> References: <20181215090325.31604-1-luca@coelho.fi> MIME-Version: 1.0 Subject: [PATCH 01/24] mac80211: suspicious RCU usage fix Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Lior Cohen Suspicious RCU usage observed while calling the cfg80211_sta_opmode_change_notify() during rx_handlers path. The issue occurred due to illegal blocking while in RCU read-side critical section. The blocking caused by an attempt to alloc skb with the GFP_KERNEL flag, which eventually call the might_sleep(). Signed-off-by: Lior Cohen Signed-off-by: Luca Coelho --- net/mac80211/rx.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/net/mac80211/rx.c b/net/mac80211/rx.c index 3bd3b5769797..a69ecfb212ed 100644 --- a/net/mac80211/rx.c +++ b/net/mac80211/rx.c @@ -3063,7 +3063,7 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx) cfg80211_sta_opmode_change_notify(sdata->dev, rx->sta->addr, &sta_opmode, - GFP_KERNEL); + GFP_ATOMIC); goto handled; } case WLAN_HT_ACTION_NOTIFY_CHANWIDTH: { @@ -3100,7 +3100,7 @@ ieee80211_rx_h_action(struct ieee80211_rx_data *rx) cfg80211_sta_opmode_change_notify(sdata->dev, rx->sta->addr, &sta_opmode, - GFP_KERNEL); + GFP_ATOMIC); goto handled; } default: