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 X-Spam-Level: X-Spam-Status: No, score=-8.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D8CEFC43613 for ; Thu, 20 Jun 2019 18:12:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id B562120645 for ; Thu, 20 Jun 2019 18:12:25 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561054345; bh=HIuE3JNFb/DYg2FOXYFgoUdtkIziSqzhWLsa9y8tBu4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:List-ID:From; b=aoxttJM+XWPJOnxygPG0HDVWxM1a8uxqQ3dOfa6T3CNpyK4TqZ7sepf280IOHZ72w DEX385LSbgHaT5dNp8YpZ00aAU2D89uSAKZCOLOlC6Akje/XBc+1d/YM56s1Goy+70 AaaATLTrzP1EY74HpqgNJM0xbnVNksmvPMGlEBaw= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729022AbfFTSMY (ORCPT ); Thu, 20 Jun 2019 14:12:24 -0400 Received: from mail.kernel.org ([198.145.29.99]:40116 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728689AbfFTSMT (ORCPT ); Thu, 20 Jun 2019 14:12:19 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id A339F2070B; Thu, 20 Jun 2019 18:12:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1561054339; bh=HIuE3JNFb/DYg2FOXYFgoUdtkIziSqzhWLsa9y8tBu4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=I+minqsiEBTck5ODXPXxUKlUBgLoeXVXZ2Rx5dSq1aL4sgA8Hmb8Uv4krts8KZw26 86dWXRG0Z4chdVsVyvLoal15W1qa5E7/8v9v47VtHiIbyrToeXEuwgvI7xXec7gQ7n yHCsqI1YPws+viY+VzMSq1ImTWJ9KDlOdZyjsBK8= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Hulk Robot , YueHaibing , Bart Van Assche , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.19 56/61] scsi: scsi_dh_alua: Fix possible null-ptr-deref Date: Thu, 20 Jun 2019 19:57:51 +0200 Message-Id: <20190620174347.001604173@linuxfoundation.org> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190620174336.357373754@linuxfoundation.org> References: <20190620174336.357373754@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [ Upstream commit 12e750bc62044de096ab9a95201213fd912b9994 ] If alloc_workqueue fails in alua_init, it should return -ENOMEM, otherwise it will trigger null-ptr-deref while unloading module which calls destroy_workqueue dereference wq->lock like this: BUG: KASAN: null-ptr-deref in __lock_acquire+0x6b4/0x1ee0 Read of size 8 at addr 0000000000000080 by task syz-executor.0/7045 CPU: 0 PID: 7045 Comm: syz-executor.0 Tainted: G C 5.1.0+ #28 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.2-1ubuntu1 Call Trace: dump_stack+0xa9/0x10e __kasan_report+0x171/0x18d ? __lock_acquire+0x6b4/0x1ee0 kasan_report+0xe/0x20 __lock_acquire+0x6b4/0x1ee0 lock_acquire+0xb4/0x1b0 __mutex_lock+0xd8/0xb90 drain_workqueue+0x25/0x290 destroy_workqueue+0x1f/0x3f0 __x64_sys_delete_module+0x244/0x330 do_syscall_64+0x72/0x2a0 entry_SYSCALL_64_after_hwframe+0x49/0xbe Reported-by: Hulk Robot Fixes: 03197b61c5ec ("scsi_dh_alua: Use workqueue for RTPG") Signed-off-by: YueHaibing Reviewed-by: Bart Van Assche Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/scsi/device_handler/scsi_dh_alua.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/device_handler/scsi_dh_alua.c b/drivers/scsi/device_handler/scsi_dh_alua.c index 12dc7100bb4c..d1154baa9436 100644 --- a/drivers/scsi/device_handler/scsi_dh_alua.c +++ b/drivers/scsi/device_handler/scsi_dh_alua.c @@ -1173,10 +1173,8 @@ static int __init alua_init(void) int r; kaluad_wq = alloc_workqueue("kaluad", WQ_MEM_RECLAIM, 0); - if (!kaluad_wq) { - /* Temporary failure, bypass */ - return SCSI_DH_DEV_TEMP_BUSY; - } + if (!kaluad_wq) + return -ENOMEM; r = scsi_register_device_handler(&alua_dh); if (r != 0) { -- 2.20.1