From nobody Tue Dec 16 16:37:07 2025 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 C8B00C28B2B for ; Fri, 19 Aug 2022 16:52:39 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1354317AbiHSQwi (ORCPT ); Fri, 19 Aug 2022 12:52:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58230 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1354468AbiHSQvA (ORCPT ); Fri, 19 Aug 2022 12:51:00 -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 A4B90D4192; Fri, 19 Aug 2022 09:14:07 -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 1F5FEB8281C; Fri, 19 Aug 2022 16:12:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 67757C433C1; Fri, 19 Aug 2022 16:12:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1660925565; bh=9+haSAmpSNCpSQ93WhxmWz6akqKUaW0JkC/VW2kYV0c=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Hy94WwflTXNBv/pFOBqAH06BThv+5/2td91uIH2ZpQPSHnDvdx9JZRFBvq1IC7nlc 5IWVY37BlsqWdcEm7ZLGa+12aaVsMBbkD3TG5JSquPB8x4ZKX6e9CCQPHH8BJm2IY4 7MfZs1m8cjEDcUDVagMjhw/C/ZXE7WmQHNsbs/PM= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Ahmed Zaki , Johannes Berg , Viacheslav Sablin Subject: [PATCH 5.10 531/545] mac80211: fix a memory leak where sta_info is not freed Date: Fri, 19 Aug 2022 17:45:01 +0200 Message-Id: <20220819153853.344912739@linuxfoundation.org> X-Mailer: git-send-email 2.37.2 In-Reply-To: <20220819153829.135562864@linuxfoundation.org> References: <20220819153829.135562864@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" From: Ahmed Zaki commit 8f9dcc29566626f683843ccac6113a12208315ca upstream. The following is from a system that went OOM due to a memory leak: wlan0: Allocated STA 74:83:c2:64:0b:87 wlan0: Allocated STA 74:83:c2:64:0b:87 wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_add_sta) wlan0: Adding new IBSS station 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 3 wlan0: Inserted STA 74:83:c2:64:0b:87 wlan0: IBSS finish 74:83:c2:64:0b:87 (---from ieee80211_ibss_work) wlan0: Adding new IBSS station 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 3 =2E =2E wlan0: expiring inactive not authorized STA 74:83:c2:64:0b:87 wlan0: moving STA 74:83:c2:64:0b:87 to state 2 wlan0: moving STA 74:83:c2:64:0b:87 to state 1 wlan0: Removed STA 74:83:c2:64:0b:87 wlan0: Destroyed STA 74:83:c2:64:0b:87 The ieee80211_ibss_finish_sta() is called twice on the same STA from 2 different locations. On the second attempt, the allocated STA is not destroyed creating a kernel memory leak. This is happening because sta_info_insert_finish() does not call sta_info_free() the second time when the STA already exists (returns -EEXIST). Note that the caller sta_info_insert_rcu() assumes STA is destroyed upon errors. Same fix is applied to -ENOMEM. Signed-off-by: Ahmed Zaki Link: https://lore.kernel.org/r/20211002145329.3125293-1-anzaki@gmail.com [change the error path label to use the existing code] Signed-off-by: Johannes Berg Signed-off-by: Viacheslav Sablin Signed-off-by: Greg Kroah-Hartman --- net/mac80211/sta_info.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/net/mac80211/sta_info.c +++ b/net/mac80211/sta_info.c @@ -645,13 +645,13 @@ static int sta_info_insert_finish(struct /* check if STA exists already */ if (sta_info_get_bss(sdata, sta->sta.addr)) { err =3D -EEXIST; - goto out_err; + goto out_cleanup; } =20 sinfo =3D kzalloc(sizeof(struct station_info), GFP_KERNEL); if (!sinfo) { err =3D -ENOMEM; - goto out_err; + goto out_cleanup; } =20 local->num_sta++; @@ -707,8 +707,8 @@ static int sta_info_insert_finish(struct out_drop_sta: local->num_sta--; synchronize_net(); + out_cleanup: cleanup_single_sta(sta); - out_err: mutex_unlock(&local->sta_mtx); kfree(sinfo); rcu_read_lock();