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 F0BCDCCA48A for ; Tue, 7 Jun 2022 22:32:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1380727AbiFGWcP (ORCPT ); Tue, 7 Jun 2022 18:32:15 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35264 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1384010AbiFGWbC (ORCPT ); Tue, 7 Jun 2022 18:31:02 -0400 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EAA80276201; Tue, 7 Jun 2022 12:24:03 -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 ams.source.kernel.org (Postfix) with ESMTPS id 5F3AEB823D6; Tue, 7 Jun 2022 19:24:02 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id C6509C36B01; Tue, 7 Jun 2022 19:24:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1654629841; bh=4v+cu7e+Xt75WklgaATgEEarc6UDXVoriEbxTMfiz7c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Y9LHnac5sSkmSc7GDLQLoC8Jo+2H3JbOw2oy7a2X0dnQp+qdGEKV/2RHlu9SVPiQL UYYvozpp96NP2b7gZkJjsAGyrcFYp92Q81wLxXz9YMqV7fhIxVV00V3egbZ04I9CIC Qy3wNHvo+RI1HKiv2tHaJ9xZeYEopCcr8zyxSZf4= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, pa@panix.com, Alexander Wetzel , Kalle Valo Subject: [PATCH 5.18 835/879] rtl818x: Prevent using not initialized queues Date: Tue, 7 Jun 2022 19:05:53 +0200 Message-Id: <20220607165027.092843914@linuxfoundation.org> X-Mailer: git-send-email 2.36.1 In-Reply-To: <20220607165002.659942637@linuxfoundation.org> References: <20220607165002.659942637@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Alexander Wetzel commit 746285cf81dc19502ab238249d75f5990bd2d231 upstream. Using not existing queues can panic the kernel with rtl8180/rtl8185 cards. Ignore the skb priority for those cards, they only have one tx queue. Pierre Asselin (pa@panix.com) reported the kernel crash in the Gentoo forum: https://forums.gentoo.org/viewtopic-t-1147832-postdays-0-postorder-asc-start-25.html He also confirmed that this patch fixes the issue. In summary this happened: After updating wpa_supplicant from 2.9 to 2.10 the kernel crashed with a "divide error: 0000" when connecting to an AP. Control port tx now tries to use IEEE80211_AC_VO for the priority, which wpa_supplicants starts to use in 2.10. Since only the rtl8187se part of the driver supports QoS, the priority of the skb is set to IEEE80211_AC_BE (2) by mac80211 for rtl8180/rtl8185 cards. rtl8180 is then unconditionally reading out the priority and finally crashes on drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c line 544 without this patch: idx = (ring->idx + skb_queue_len(&ring->queue)) % ring->entries "ring->entries" is zero for rtl8180/rtl8185 cards, tx_ring[2] never got initialized. Cc: stable@vger.kernel.org Reported-by: pa@panix.com Tested-by: pa@panix.com Signed-off-by: Alexander Wetzel Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/20220422145228.7567-1-alexander@wetzel-home.de Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) --- a/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c +++ b/drivers/net/wireless/realtek/rtl818x/rtl8180/dev.c @@ -460,8 +460,10 @@ static void rtl8180_tx(struct ieee80211_ struct rtl8180_priv *priv = dev->priv; struct rtl8180_tx_ring *ring; struct rtl8180_tx_desc *entry; + unsigned int prio = 0; unsigned long flags; - unsigned int idx, prio, hw_prio; + unsigned int idx, hw_prio; + dma_addr_t mapping; u32 tx_flags; u8 rc_flags; @@ -470,7 +472,9 @@ static void rtl8180_tx(struct ieee80211_ /* do arithmetic and then convert to le16 */ u16 frame_duration = 0; - prio = skb_get_queue_mapping(skb); + /* rtl8180/rtl8185 only has one useable tx queue */ + if (dev->queues > IEEE80211_AC_BK) + prio = skb_get_queue_mapping(skb); ring = &priv->tx_ring[prio]; mapping = dma_map_single(&priv->pdev->dev, skb->data, skb->len,