From mboxrd@z Thu Jan 1 00:00:00 1970 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 9FF07C77B7A for ; Thu, 25 May 2023 18:36:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241932AbjEYSgl (ORCPT ); Thu, 25 May 2023 14:36:41 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241929AbjEYSgM (ORCPT ); Thu, 25 May 2023 14:36:12 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B87AB1715; Thu, 25 May 2023 11:34:45 -0700 (PDT) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 99623648D3; Thu, 25 May 2023 18:34:45 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBD64C433AC; Thu, 25 May 2023 18:34:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1685039685; bh=H2VwrVzS+U9B6jNfgMZ8PZWDi0r+a9pquf7BqrvT6iU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=JHiuUBeK822+cO2K7Su+WBYxSYXj0WNhBznNlnmPUew6UD6bxnNQdRHXM1Mx5nqgr hAdgMlV1CQd7XFhTB9207THRyFoH7LTBiN8WT4uGY3LdUDe72zH+3iQiVTjcGkLd6P YrLia3uHiGQJEzLM8WAmVu9YXkvueo9jIl0tre5eGRsD1NTjrpcJqwFx2xX8SJglid leT2/FyB95xNyOuMuSgWnAZsK1s+ULx0xQf/PAer7UvmAuEEEn5JCLMxkWpXiATbb1 VI9UhEHgW6EW/fit4FBAAkWSCIii71WSkfbKnFVygq69zvE+krUCmVDI4DpgIT2IM3 3My1yX9YeYRqA== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Ariel Malamud , Gregory Greenman , Johannes Berg , Sasha Levin , kvalo@kernel.org, benjamin.berg@intel.com, trix@redhat.com, mordechay.goodstein@intel.com, linux-wireless@vger.kernel.org Subject: [PATCH AUTOSEL 6.3 48/67] wifi: iwlwifi: mvm: Add locking to the rate read flow Date: Thu, 25 May 2023 14:31:25 -0400 Message-Id: <20230525183144.1717540-48-sashal@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20230525183144.1717540-1-sashal@kernel.org> References: <20230525183144.1717540-1-sashal@kernel.org> MIME-Version: 1.0 X-stable: review X-Patchwork-Hint: Ignore Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Ariel Malamud [ Upstream commit a8938bc881d2a03f9b77f19fae924fe798a01285 ] The rs_drv_get_rate flow reads the lq_sta to return the optimal rate for tx frames. This read flow is not protected thereby leaving a small window, a few instructions wide, open to contention by an asynchronous rate update. Indeed this race condition was hit and the update occurred in the middle of the read. Fix this by locking the lq_sta struct during read. Signed-off-by: Ariel Malamud Signed-off-by: Gregory Greenman Link: https://lore.kernel.org/r/20230514120631.b52c9ed5c379.I15290b78e0d966c1b68278263776ca9de841d5fe@changeid Signed-off-by: Johannes Berg Signed-off-by: Sasha Levin --- drivers/net/wireless/intel/iwlwifi/mvm/rs.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/rs.c b/drivers/net/wireless/intel/iwlwifi/mvm/rs.c index 0b50b816684a0..2be6801d48aca 100644 --- a/drivers/net/wireless/intel/iwlwifi/mvm/rs.c +++ b/drivers/net/wireless/intel/iwlwifi/mvm/rs.c @@ -2692,6 +2692,8 @@ static void rs_drv_get_rate(void *mvm_r, struct ieee80211_sta *sta, return; lq_sta = mvm_sta; + + spin_lock(&lq_sta->pers.lock); iwl_mvm_hwrate_to_tx_rate_v1(lq_sta->last_rate_n_flags, info->band, &info->control.rates[0]); info->control.rates[0].count = 1; @@ -2706,6 +2708,7 @@ static void rs_drv_get_rate(void *mvm_r, struct ieee80211_sta *sta, iwl_mvm_hwrate_to_tx_rate_v1(last_ucode_rate, info->band, &txrc->reported_rate); } + spin_unlock(&lq_sta->pers.lock); } static void *rs_drv_alloc_sta(void *mvm_rate, struct ieee80211_sta *sta, -- 2.39.2