From patchwork Tue Nov 12 03:57:51 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Bart Van Assche X-Patchwork-Id: 11238523 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 8157E159A for ; Tue, 12 Nov 2019 03:58:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 6A06B2084E for ; Tue, 12 Nov 2019 03:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726927AbfKLD6E (ORCPT ); Mon, 11 Nov 2019 22:58:04 -0500 Received: from mail-pf1-f194.google.com ([209.85.210.194]:45385 "EHLO mail-pf1-f194.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726910AbfKLD6E (ORCPT ); Mon, 11 Nov 2019 22:58:04 -0500 Received: by mail-pf1-f194.google.com with SMTP id z4so12320380pfn.12 for ; Mon, 11 Nov 2019 19:58:03 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=qQsBDiPkxtL928atho+ukThThK4lob1as5aFbJEM/XA=; b=Pa+DVt5YXnUjimnhbBcjc4U8Xx41fy7xrsbaRHihjoNzi1N7HKxhfxtHdvlLl5dfOv aO9eGfR7IKDofyJi8r0It9ys5MaeJILshXftxDQ74ocueN9F9t5ow5SkS5JZQttEcjTw PGVmYEbWUXvmELUDA8MVWw0gMIods0vSZ6FKHbN9sG4OKVmx4oMTndMkI1mv/xs2eHR5 +m3a4ZIJfYfPWssTPpFZcd/MFhVm8VoTZcl9DL9rmZQJPPoW2vJs5jv6L1IUqFvGaEO0 l2Ss4mBqHNW0EsFLoMvz8FWO5vAqWERmySGDWtUR7b0+iNmiA45MIqvep1W198pJ7hnc jqqQ== X-Gm-Message-State: APjAAAXufmdEVwnyhbyAjqRcEBaRauYYunZaX6QZwTQduyXnVEHDG+qu 1f3fipOBrLEBYf5uU+DoCcI= X-Google-Smtp-Source: APXvYqzKPBtgMo4mMTX5F2AHF8WWZ5fM25oSFGQ+tM9ADGxKsqYH/IkBv9OuDeowWzL/iWRJnWZo7Q== X-Received: by 2002:a17:90b:30ca:: with SMTP id hi10mr3481014pjb.143.1573531083264; Mon, 11 Nov 2019 19:58:03 -0800 (PST) Received: from asus.hsd1.ca.comcast.net ([2601:647:4000:a8:97:b734:6b8f:663c]) by smtp.gmail.com with ESMTPSA id e5sm784288pjv.29.2019.11.11.19.58.01 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Nov 2019 19:58:02 -0800 (PST) From: Bart Van Assche To: "Martin K . Petersen" Cc: Mike Christie , Roman Bolshakov , Christoph Hellwig , target-devel@vger.kernel.org, Bart Van Assche Subject: [PATCH 2/3] target/core: Fix a use-after-free in the TMF handling code Date: Mon, 11 Nov 2019 19:57:51 -0800 Message-Id: <20191112035752.8338-3-bvanassche@acm.org> X-Mailer: git-send-email 2.23.0 In-Reply-To: <20191112035752.8338-1-bvanassche@acm.org> References: <20191112035752.8338-1-bvanassche@acm.org> MIME-Version: 1.0 Sender: target-devel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: target-devel@vger.kernel.org The target_remove_from_state_list() call uses the cmd->dev pointer. Make sure that that pointer remains valid as long as TMF processing is in progress. This patch fixes the following KASAN complaint: BUG: KASAN: use-after-free in target_remove_from_state_list+0x22/0x130 [target_core_mod] Read of size 8 at addr ffff8880b110cf80 by task kworker/0:1/12 CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.4.0-rc1-dbg+ #6 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 Workqueue: events target_tmr_work [target_core_mod] Call Trace: dump_stack+0x8a/0xd6 print_address_description.constprop.0+0x40/0x60 __kasan_report.cold+0x1b/0x33 kasan_report+0x16/0x20 __asan_load8+0x58/0x90 target_remove_from_state_list+0x22/0x130 [target_core_mod] transport_cmd_check_stop_to_fabric+0x17/0xe0 [target_core_mod] target_tmr_work+0xe2/0x1a0 [target_core_mod] process_one_work+0x549/0xa40 worker_thread+0x7a/0x5d0 kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 The buggy address belongs to the page: page:ffffea0002c44300 refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0x1fff000000000000() raw: 1fff000000000000 0000000000000000 ffffea0002c44308 0000000000000000 raw: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880b110ce80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880b110cf00: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff >ffff8880b110cf80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ^ ffff8880b110d000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff8880b110d080: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff Cc: Mike Christie Cc: Roman Bolshakov Signed-off-by: Bart Van Assche --- drivers/target/target_core_transport.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index 09f833c1de8a..ba6bd73fe63b 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -3256,6 +3256,8 @@ static void target_tmr_work(struct work_struct *work) struct se_tmr_req *tmr = cmd->se_tmr_req; int ret; + target_depend_item(&dev->dev_group.cg_item); + if (cmd->transport_state & CMD_T_ABORTED) goto aborted; @@ -3297,10 +3299,14 @@ static void target_tmr_work(struct work_struct *work) cmd->se_tfo->queue_tm_rsp(cmd); transport_cmd_check_stop_to_fabric(cmd); + +out: + target_undepend_item(&dev->dev_group.cg_item); return; aborted: target_handle_abort(cmd); + goto out; } int transport_generic_handle_tmr(