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 F0897C67871 for ; Mon, 24 Oct 2022 20:25:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230057AbiJXUZT (ORCPT ); Mon, 24 Oct 2022 16:25:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38002 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233437AbiJXUXR (ORCPT ); Mon, 24 Oct 2022 16:23:17 -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 C7F61349A3; Mon, 24 Oct 2022 11:38:42 -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 0D291B815DA; Mon, 24 Oct 2022 12:12:13 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 6317DC433D6; Mon, 24 Oct 2022 12:12:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1666613531; bh=Eq053hQgh5hot3gFniUkU0XCEGYQXU6z0x6OdiZi4KQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=ciSoZHLSmjYelPs7J4blb48JzNkjfZS5yekCOzQqBtYr1yGWIMNB16s3znGxuPldz 3LdP/qmZZwRM8EEeL+06ssTdpfnl2nUjiRE43DHcBXL968RawoOggiDAc15U7ENwco ESCyKaLtZvvT5UE3tbLK5x+h9EGVvcCE3rFgXJS8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Jason Yan , Duoming Zhou , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 5.4 155/255] scsi: libsas: Fix use-after-free bug in smp_execute_task_sg() Date: Mon, 24 Oct 2022 13:31:05 +0200 Message-Id: <20221024113007.799761629@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 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Duoming Zhou [ Upstream commit 46ba53c30666717cb06c2b3c5d896301cd00d0c0 ] When executing SMP task failed, the smp_execute_task_sg() calls del_timer() to delete "slow_task->timer". However, if the timer handler sas_task_internal_timedout() is running, the del_timer() in smp_execute_task_sg() will not stop it and a UAF will happen. The process is shown below: (thread 1) | (thread 2) smp_execute_task_sg() | sas_task_internal_timedout() ... | del_timer() | ... | ... sas_free_task(task) | kfree(task->slow_task) //FREE| | task->slow_task->... //USE Fix by calling del_timer_sync() in smp_execute_task_sg(), which makes sure the timer handler have finished before the "task->slow_task" is deallocated. Link: https://lore.kernel.org/r/20220920144213.10536-1-duoming@zju.edu.cn Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver") Reviewed-by: Jason Yan Signed-off-by: Duoming Zhou Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/libsas/sas_expander.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/scsi/libsas/sas_expander.c b/drivers/scsi/libsas/sas_expander.c index 9fdb9c9fbda4..173f91ae38f0 100644 --- a/drivers/scsi/libsas/sas_expander.c +++ b/drivers/scsi/libsas/sas_expander.c @@ -85,7 +85,7 @@ static int smp_execute_task_sg(struct domain_device *dev, res = i->dft->lldd_execute_task(task, GFP_KERNEL); if (res) { - del_timer(&task->slow_task->timer); + del_timer_sync(&task->slow_task->timer); pr_notice("executing SMP task failed:%d\n", res); break; } -- 2.35.1