From patchwork Wed Jul 14 09:18:48 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ryder Lee X-Patchwork-Id: 12376341 X-Patchwork-Delegate: nbd@nbd.name 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY,URIBL_BLOCKED, 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 C6F44C07E9C for ; Wed, 14 Jul 2021 09:18:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B1A7561369 for ; Wed, 14 Jul 2021 09:18:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238769AbhGNJVu (ORCPT ); Wed, 14 Jul 2021 05:21:50 -0400 Received: from mailgw02.mediatek.com ([210.61.82.184]:40602 "EHLO mailgw02.mediatek.com" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S238291AbhGNJVs (ORCPT ); Wed, 14 Jul 2021 05:21:48 -0400 X-UUID: 9dd61a7b90fd4f889a1089211f52885b-20210714 X-UUID: 9dd61a7b90fd4f889a1089211f52885b-20210714 Received: from mtkcas06.mediatek.inc [(172.21.101.30)] by mailgw02.mediatek.com (envelope-from ) (Generic MTA with TLSv1.2 ECDHE-RSA-AES256-SHA384 256/256) with ESMTP id 1640123618; Wed, 14 Jul 2021 17:18:53 +0800 Received: from mtkcas07.mediatek.inc (172.21.101.84) by mtkmbs05n1.mediatek.inc (172.21.101.15) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Wed, 14 Jul 2021 17:18:52 +0800 Received: from mtksdccf07.mediatek.inc (172.21.84.99) by mtkcas07.mediatek.inc (172.21.101.73) with Microsoft SMTP Server id 15.0.1497.2 via Frontend Transport; Wed, 14 Jul 2021 17:18:52 +0800 From: Ryder Lee To: Felix Fietkau CC: Lorenzo Bianconi , Shayne Chen , Evelyn Tsai , , , Ryder Lee Subject: [PATCH v2 1/4] mt76 mt7915: take RCU read lock when calling ieee80211_bss_get_elem() Date: Wed, 14 Jul 2021 17:18:48 +0800 Message-ID: <50730853fe09fb75418484770a0c95c23b44deb5.1626253920.git.ryder.lee@mediatek.com> X-Mailer: git-send-email 2.18.0 MIME-Version: 1.0 X-MTK: N Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org As ieee80211_bss_get_elem() derefences an RCU to return ie, both the call to this function and any operation on this variable need protection by the RCU read lock. Signed-off-by: Ryder Lee --- v2 - fix typo in commit message --- drivers/net/wireless/mediatek/mt76/mt7915/mcu.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c index 863aa18b3024..4d2e5b5e6389 100644 --- a/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c +++ b/drivers/net/wireless/mediatek/mt76/mt7915/mcu.c @@ -923,12 +923,15 @@ static void mt7915_check_he_obss_narrow_bw_ru_iter(struct wiphy *wiphy, struct mt7915_he_obss_narrow_bw_ru_data *data = _data; const struct element *elem; + rcu_read_lock(); elem = ieee80211_bss_get_elem(bss, WLAN_EID_EXT_CAPABILITY); if (!elem || elem->datalen < 10 || !(elem->data[10] & WLAN_EXT_CAPA10_OBSS_NARROW_BW_RU_TOLERANCE_SUPPORT)) data->tolerated = false; + + rcu_read_unlock(); } static bool mt7915_check_he_obss_narrow_bw_ru(struct ieee80211_hw *hw,