From patchwork Mon Oct 24 11:29:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Greg KH X-Patchwork-Id: 10228 Return-Path: Delivered-To: ouuuleilei@gmail.com Received: by 2002:a5d:6687:0:0:0:0:0 with SMTP id l7csp642940wru; Mon, 24 Oct 2022 13:40:01 -0700 (PDT) X-Google-Smtp-Source: AMsMyM6YXZMn8kEoO4O7/5EhwSxZzTuihF2T+FtMjXwqeVdB84N493FZP92txdJ0CdqrQhhiHRVD X-Received: by 2002:a17:902:cac3:b0:186:6ce4:f94a with SMTP id y3-20020a170902cac300b001866ce4f94amr22396319pld.145.1666644001332; Mon, 24 Oct 2022 13:40:01 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1666644001; cv=none; d=google.com; s=arc-20160816; b=IVxOldz/TEqEF1hHFqFf7gpPlLdVq9J1S9IrFr2Uczi+7e8KtJS1NhyXd49qoxJDqt G4SNDO1i7BJQCxsBRMYHW0qtAOfZRli4WgIONCbVKaq29ZA9pq4UaJbUO3EtufMoQjML ql8UHmFR6viBMGLTxeO8E3sCGn84xx5UrCq7zkzSKPexQvgE6Fjc9LBISGpVwCPYPDG6 +ayKiMLSxEHTS7qXnIQitPdtHZkcG3L7VqDhvHVEteQ6O3fB8xWXNnnZ1d0ODv+s9/2I ZZFa8ts37RQ3sQm8ssLwW7JPJYjiprnjPTm9fE5PJtrLJN9043TS12xT/nqzn4eUQ3Kk qZhg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :user-agent:references:in-reply-to:message-id:date:subject:cc:to :from:dkim-signature; bh=YyBJTR+ihSnlgsZKObYqzucWb98ATOZT2eXgF5w7dUY=; b=MvsrKb2dLv3kOc1teTG6C7lfIOeLx1er0QYr57kNF8uZ5cZ+uOZE0RW3761tZgp/3J iR7M+OMQCLvBlqtCYyY5DvYBAQNk/wSSq7KCm/feW60lb+c6BUl/P0FwQhiydsTeLuny OfMK3UrmQLjicv94Wld4eAz4D100ev0IaJVRRgjEmQGgYw6EYzrbFDsm9nnlbLHyyIOY i/hCnvGOYhDIzYDb4nzPkohius03pDqHsnoovBMu5q4mQerdiEj1q0h5gHYVRs4fo11P I02bzxIz+EQxcZC81PlXmy4v72U4PCjWfhodsfpWs0uEd6Yo9wxZ940z9CWF4VDdfs89 T6LQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=lq9UPjIi; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id a22-20020a17090a6d9600b002130d0f6df8si920690pjk.30.2022.10.24.13.39.48; Mon, 24 Oct 2022 13:40:01 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@linuxfoundation.org header.s=korg header.b=lq9UPjIi; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=linuxfoundation.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234648AbiJXUiu (ORCPT + 99 others); Mon, 24 Oct 2022 16:38:50 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:40000 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234609AbiJXUiL (ORCPT ); Mon, 24 Oct 2022 16:38:11 -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 627DF3FA20; Mon, 24 Oct 2022 11:49:32 -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 459C7B81256; Mon, 24 Oct 2022 12:08:11 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D5B4C433C1; Mon, 24 Oct 2022 12:08:09 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666613290; bh=J07xhHpiz53nfpmBnVPX+Nux9GuiPCo4H7qkooMzdPM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=lq9UPjIiFzE/GppoS4G8T04RWcw7z2uGTbNjRl6OYm7HvqSF3xP70mE+6/AkZMmpV T7zsEvsUdAyvmSj355NPoWvN1u6Z8+8gdWOMYO1p47Cj0l+G3NOkXaH7J9V2iBid2O 8fHCno3B9NL3ozRjWoGyaquvV+4jOT6eV71Qa/ZA= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Duoming Zhou , Leon Romanovsky , "David S. Miller" , Sasha Levin Subject: [PATCH 5.4 080/255] mISDN: fix use-after-free bugs in l1oip timer handlers Date: Mon, 24 Oct 2022 13:29:50 +0200 Message-Id: <20221024113005.169495890@linuxfoundation.org> X-Mailer: git-send-email 2.38.1 In-Reply-To: <20221024113002.471093005@linuxfoundation.org> References: <20221024113002.471093005@linuxfoundation.org> User-Agent: quilt/0.67 MIME-Version: 1.0 X-Spam-Status: No, score=-7.6 required=5.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI, SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1747602900587379142?= X-GMAIL-MSGID: =?utf-8?q?1747602900587379142?= From: Duoming Zhou [ Upstream commit 2568a7e0832ee30b0a351016d03062ab4e0e0a3f ] The l1oip_cleanup() traverses the l1oip_ilist and calls release_card() to cleanup module and stack. However, release_card() calls del_timer() to delete the timers such as keep_tl and timeout_tl. If the timer handler is running, the del_timer() will not stop it and result in UAF bugs. One of the processes is shown below: (cleanup routine) | (timer handler) release_card() | l1oip_timeout() ... | del_timer() | ... ... | kfree(hc) //FREE | | hc->timeout_on = 0 //USE Fix by calling del_timer_sync() in release_card(), which makes sure the timer handlers have finished before the resources, such as l1oip and so on, have been deallocated. What's more, the hc->workq and hc->socket_thread can kick those timers right back in. We add a bool flag to show if card is released. Then, check this flag in hc->workq and hc->socket_thread. Fixes: 3712b42d4b1b ("Add layer1 over IP support") Signed-off-by: Duoming Zhou Reviewed-by: Leon Romanovsky Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- drivers/isdn/mISDN/l1oip.h | 1 + drivers/isdn/mISDN/l1oip_core.c | 13 +++++++------ 2 files changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/isdn/mISDN/l1oip.h b/drivers/isdn/mISDN/l1oip.h index 7ea10db20e3a..48133d022812 100644 --- a/drivers/isdn/mISDN/l1oip.h +++ b/drivers/isdn/mISDN/l1oip.h @@ -59,6 +59,7 @@ struct l1oip { int bundle; /* bundle channels in one frm */ int codec; /* codec to use for transmis. */ int limit; /* limit number of bchannels */ + bool shutdown; /* if card is released */ /* timer */ struct timer_list keep_tl; diff --git a/drivers/isdn/mISDN/l1oip_core.c b/drivers/isdn/mISDN/l1oip_core.c index b57dcb834594..aec4f2a69c3b 100644 --- a/drivers/isdn/mISDN/l1oip_core.c +++ b/drivers/isdn/mISDN/l1oip_core.c @@ -275,7 +275,7 @@ l1oip_socket_send(struct l1oip *hc, u8 localcodec, u8 channel, u32 chanmask, p = frame; /* restart timer */ - if (time_before(hc->keep_tl.expires, jiffies + 5 * HZ)) + if (time_before(hc->keep_tl.expires, jiffies + 5 * HZ) && !hc->shutdown) mod_timer(&hc->keep_tl, jiffies + L1OIP_KEEPALIVE * HZ); else hc->keep_tl.expires = jiffies + L1OIP_KEEPALIVE * HZ; @@ -601,7 +601,9 @@ l1oip_socket_parse(struct l1oip *hc, struct sockaddr_in *sin, u8 *buf, int len) goto multiframe; /* restart timer */ - if (time_before(hc->timeout_tl.expires, jiffies + 5 * HZ) || !hc->timeout_on) { + if ((time_before(hc->timeout_tl.expires, jiffies + 5 * HZ) || + !hc->timeout_on) && + !hc->shutdown) { hc->timeout_on = 1; mod_timer(&hc->timeout_tl, jiffies + L1OIP_TIMEOUT * HZ); } else /* only adjust timer */ @@ -1232,11 +1234,10 @@ release_card(struct l1oip *hc) { int ch; - if (timer_pending(&hc->keep_tl)) - del_timer(&hc->keep_tl); + hc->shutdown = true; - if (timer_pending(&hc->timeout_tl)) - del_timer(&hc->timeout_tl); + del_timer_sync(&hc->keep_tl); + del_timer_sync(&hc->timeout_tl); cancel_work_sync(&hc->workq);