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 747BEC25B0E for ; Mon, 15 Aug 2022 18:13:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233033AbiHOSNj (ORCPT ); Mon, 15 Aug 2022 14:13:39 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57902 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232540AbiHOSNb (ORCPT ); Mon, 15 Aug 2022 14:13:31 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5B6D56333; Mon, 15 Aug 2022 11:13:29 -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 ECF5261272; Mon, 15 Aug 2022 18:13:28 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 055E3C433D6; Mon, 15 Aug 2022 18:13:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660587208; bh=o/WIXOViD9vWqopC59+UoXlSaz8ouCZte8mYCBqVsMM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=IPHD5O26ISpNJOU3vnkdHINKr2p9DerI7Hx8KiQHy+VoKUXt8qde6qc7QQSx22J3V 1qCms9oqWxLk5EggZBcIB7Np7VkaBrnCpLzKpU76+Sb78K3qLABXtCzDnYrxxqgblX Q0C7c6c8lhWsQYGAShHZawqAmCcbiMv0PP4FZCLg= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jeongik Cha , Johannes Berg Subject: [PATCH 5.15 012/779] wifi: mac80211_hwsim: fix race condition in pending packet Date: Mon, 15 Aug 2022 19:54:16 +0200 Message-Id: <20220815180337.715947353@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220815180337.130757997@linuxfoundation.org> References: <20220815180337.130757997@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Jeongik Cha commit 4ee186fa7e40ae06ebbfbad77e249e3746e14114 upstream. A pending packet uses a cookie as an unique key, but it can be duplicated because it didn't use atomic operators. And also, a pending packet can be null in hwsim_tx_info_frame_received_nl due to race condition with mac80211_hwsim_stop. For this, * Use an atomic type and operator for a cookie * Add a lock around the loop for pending packets Signed-off-by: Jeongik Cha Link: https://lore.kernel.org/r/20220704084354.3556326-1-jeongik@google.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/mac80211_hwsim.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) --- a/drivers/net/wireless/mac80211_hwsim.c +++ b/drivers/net/wireless/mac80211_hwsim.c @@ -663,7 +663,7 @@ struct mac80211_hwsim_data { bool ps_poll_pending; struct dentry *debugfs; - uintptr_t pending_cookie; + atomic64_t pending_cookie; struct sk_buff_head pending; /* packets pending */ /* * Only radios in the same group can communicate together (the @@ -1270,7 +1270,7 @@ static void mac80211_hwsim_tx_frame_nl(s int i; struct hwsim_tx_rate tx_attempts[IEEE80211_TX_MAX_RATES]; struct hwsim_tx_rate_flag tx_attempts_flags[IEEE80211_TX_MAX_RATES]; - uintptr_t cookie; + u64 cookie; if (data->ps != PS_DISABLED) hdr->frame_control |= cpu_to_le16(IEEE80211_FCTL_PM); @@ -1339,8 +1339,7 @@ static void mac80211_hwsim_tx_frame_nl(s goto nla_put_failure; /* We create a cookie to identify this skb */ - data->pending_cookie++; - cookie = data->pending_cookie; + cookie = (u64)atomic64_inc_return(&data->pending_cookie); info->rate_driver_data[0] = (void *)cookie; if (nla_put_u64_64bit(skb, HWSIM_ATTR_COOKIE, cookie, HWSIM_ATTR_PAD)) goto nla_put_failure; @@ -3582,6 +3581,7 @@ static int hwsim_tx_info_frame_received_ const u8 *src; unsigned int hwsim_flags; int i; + unsigned long flags; bool found = false; if (!info->attrs[HWSIM_ATTR_ADDR_TRANSMITTER] || @@ -3609,18 +3609,20 @@ static int hwsim_tx_info_frame_received_ } /* look for the skb matching the cookie passed back from user */ + spin_lock_irqsave(&data2->pending.lock, flags); skb_queue_walk_safe(&data2->pending, skb, tmp) { u64 skb_cookie; txi = IEEE80211_SKB_CB(skb); - skb_cookie = (u64)(uintptr_t)txi->rate_driver_data[0]; + skb_cookie = (u64)txi->rate_driver_data[0]; if (skb_cookie == ret_skb_cookie) { - skb_unlink(skb, &data2->pending); + __skb_unlink(skb, &data2->pending); found = true; break; } } + spin_unlock_irqrestore(&data2->pending.lock, flags); /* not found */ if (!found)