From patchwork Sun Mar 27 07:27:02 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Xiaomeng Tong X-Patchwork-Id: 554792 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 CEA0BC433FE for ; Sun, 27 Mar 2022 07:27:19 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232931AbiC0H2z (ORCPT ); Sun, 27 Mar 2022 03:28:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:39958 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231258AbiC0H2w (ORCPT ); Sun, 27 Mar 2022 03:28:52 -0400 Received: from mail-pj1-x102a.google.com (mail-pj1-x102a.google.com [IPv6:2607:f8b0:4864:20::102a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D8F2C1AA; Sun, 27 Mar 2022 00:27:14 -0700 (PDT) Received: by mail-pj1-x102a.google.com with SMTP id mp6-20020a17090b190600b001c6841b8a52so15914664pjb.5; Sun, 27 Mar 2022 00:27:14 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=from:to:cc:subject:date:message-id; bh=n9/pEZe4CVIlbTMI+5XnBEGK7G61xg7386/V4aygmpk=; b=AC0WM2AVMdygcMQI3kxiOA8DrMyQGAHIMbqEmMfQjs0SVXcbPOgbxB9yGoGQj4QxNB IsD/aOLdn0QIScg+l9Zw9WlaWOg/FuyS79K8XFIkXchRQIZbSmhfyvDTHIxsgtgM5+Bz uE6WQL3KB5DUxLXAkYBMB06BiGQZosxrn8Zr7+NM+6qBCqpJAE6h/f3Vap5+J8Kw8kqt ScAKizIZVDPLi5Ma4p9F9IwRqQuOq1Au7kGcOfxw8UAkih+AMMryNTmraT7vWjzGu0xR ekst2gz8wUZbuqAAKeY4OZ0ja3+vXZwPzKyicR0nJZt/0rYb/UL2hXsa0rycuI7zCcro 6ygQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=n9/pEZe4CVIlbTMI+5XnBEGK7G61xg7386/V4aygmpk=; b=1UbyxYhWVCKwuPp7YT1EDs6uctRbElBnfBGKkzDCpelLpY62RhyrVUaxd9S3Sxp9B3 UHB4rt1BggqRaaNGxdzTWok6MQDm5RHtEYW/k6d9RU9tQ/vaofZrmjzyLhTJx2KadhnO CkfoZQD5V+/h4O+QVZuUuIUoK9k9Jxg5TFfkH7xVc92Cf3+L6IkdrGPYQTMw+897/quc Sx0ZKGRKfBZBo9yywCr3xVaRYT8xxyfRxDjpPyTAvsDTDXQ8FrvFj+ZZfknggFjPNUU+ 72evfvjMaDgfJeEMhdMU8tWm0wVJIjKKko0cbOFCbBfgKw5tU9D+WvLEj3jZdn2Eq3/4 yRxg== X-Gm-Message-State: AOAM532Ik5yovLVYpaqSHoTPrGrCTJFbLxMErJTCoZlTA1SpdFxyH8ub uNFryaNGtqqdlG64fMZCZLB9XLc3Ttw= X-Google-Smtp-Source: ABdhPJyh7pdLOYjp9eQBvLX4DKW/kDutV8c/qbXO0yCtGASPAWv3+GsXvqTbznbRNkKlK8SS49Ztjw== X-Received: by 2002:a17:902:b705:b0:154:a806:5325 with SMTP id d5-20020a170902b70500b00154a8065325mr20279246pls.30.1648366034359; Sun, 27 Mar 2022 00:27:14 -0700 (PDT) Received: from localhost ([115.220.243.108]) by smtp.gmail.com with ESMTPSA id x7-20020a056a00188700b004fae6f0d3e5sm12463742pfh.175.2022.03.27.00.27.12 (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Sun, 27 Mar 2022 00:27:13 -0700 (PDT) From: Xiaomeng Tong To: chunkeey@googlemail.com Cc: kvalo@kernel.org, davem@davemloft.net, kuba@kernel.org, pabeni@redhat.com, linville@tuxdriver.com, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, Xiaomeng Tong , stable@vger.kernel.org Subject: [PATCH] carl9170: main: fix an incorrect use of list iterator Date: Sun, 27 Mar 2022 15:27:02 +0800 Message-Id: <20220327072702.10572-1-xiam0nd.tong@gmail.com> X-Mailer: git-send-email 2.17.1 Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org The bug is here: rcu_assign_pointer(ar->tx_ampdu_iter, (struct carl9170_sta_tid *) &ar->tx_ampdu_list); The 'ar->tx_ampdu_iter' is used as a list iterator variable which point to a structure object containing the list HEAD (&ar->tx_ampdu_list), not as the HEAD itself. The only use case of 'ar->tx_ampdu_iter' is as a base pos for list_for_each_entry_continue_rcu in carl9170_tx_ampdu(). If the iterator variable holds the *wrong* HEAD value here (has not been modified elsewhere before), this will lead to an invalid memory access. Using list_entry_rcu to get the right list iterator variable and reassign it, to fix this bug. Note: use 'ar->tx_ampdu_list.next' instead of '&ar->tx_ampdu_list' to avoid compiler error. Cc: stable@vger.kernel.org Fixes: fe8ee9ad80b28 ("carl9170: mac80211 glue and command interface") Signed-off-by: Xiaomeng Tong --- drivers/net/wireless/ath/carl9170/main.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/net/wireless/ath/carl9170/main.c b/drivers/net/wireless/ath/carl9170/main.c index 49f7ee1c912b..a287937bf666 100644 --- a/drivers/net/wireless/ath/carl9170/main.c +++ b/drivers/net/wireless/ath/carl9170/main.c @@ -1756,6 +1756,7 @@ static const struct ieee80211_ops carl9170_ops = { void *carl9170_alloc(size_t priv_size) { + struct carl9170_sta_tid *tid_info; struct ieee80211_hw *hw; struct ar9170 *ar; struct sk_buff *skb; @@ -1815,8 +1816,9 @@ void *carl9170_alloc(size_t priv_size) INIT_DELAYED_WORK(&ar->stat_work, carl9170_stat_work); INIT_DELAYED_WORK(&ar->tx_janitor, carl9170_tx_janitor); INIT_LIST_HEAD(&ar->tx_ampdu_list); - rcu_assign_pointer(ar->tx_ampdu_iter, - (struct carl9170_sta_tid *) &ar->tx_ampdu_list); + tid_info = list_entry_rcu(ar->tx_ampdu_list.next, + struct carl9170_sta_tid, list); + rcu_assign_pointer(ar->tx_ampdu_iter, tid_info); bitmap_zero(&ar->vif_bitmap, ar->fw.vif_num); INIT_LIST_HEAD(&ar->vif_list);