From patchwork Tue Nov 12 03:57:50 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: 11238525 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 C4316139A for ; Tue, 12 Nov 2019 03:58:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id AD0F72084E for ; Tue, 12 Nov 2019 03:58:05 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726939AbfKLD6F (ORCPT ); Mon, 11 Nov 2019 22:58:05 -0500 Received: from mail-pg1-f195.google.com ([209.85.215.195]:39371 "EHLO mail-pg1-f195.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726910AbfKLD6F (ORCPT ); Mon, 11 Nov 2019 22:58:05 -0500 Received: by mail-pg1-f195.google.com with SMTP id 29so10928134pgm.6 for ; Mon, 11 Nov 2019 19:58:02 -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=O5hgdp2lFIg4CqxbA59bUR69tQdjiIQGuAMAXwbl+WA=; b=luaEeFRJsz+4ARFGCrLl+EnV5OYEvnV4QAjXoQLNlt6xcCK2baluQtagQXqJISefCz r0kKuu8YNflrN6XO91JVyZm0UyXFrmKCAQbmd04uQLTXjtb791grCplRRalfuSbd9hkZ dMq0coi4+7NBxyi1R8200A5vXHBt9bT7rZX+vFCvoEgsDfZoeg0I/1s+yW2MkVozZBkg o9VqoGTkbV74X75URIn2J9Thuzta+dUwq/4nDhRCs3lCqbePh3wj7XDXXwoF81nU4Sve KEKUlQTNQe47/7hUEgY+UbgSWt/4kpbpFOZ9yc0PARFQteIj9p9n7iZwE0IC/2yJuoi5 4RpQ== X-Gm-Message-State: APjAAAWHdHTlnHRcOMjD4YgcMh+HJd23Xrefpjz2PgRTwJJoivqOGi/E iGmdy6jOsDG9ycYWtuyBq+m5Y2FW X-Google-Smtp-Source: APXvYqwdLZTBqKSWIfV70OQoedlDOlADa4viuus4oMNFxW/Ste5tqN2JFzA3cIN/X1TH6BaHjxPs8Q== X-Received: by 2002:a62:8243:: with SMTP id w64mr26043805pfd.0.1573531081961; Mon, 11 Nov 2019 19:58:01 -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.29.2019.11.11.19.58.00 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 11 Nov 2019 19:58:01 -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 1/3] target/core: Release SPC-2 reservations when closing a session Date: Mon, 11 Nov 2019 19:57:50 -0800 Message-Id: <20191112035752.8338-2-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 Release reservations when closing a session as required by SPC-2. Running the libiscsi tests triggers the KASAN complaint shown below. This patch fixes that use-after-free. BUG: KASAN: use-after-free in target_check_reservation+0x171/0x980 [target_core_mod] Read of size 8 at addr ffff88802ecd1878 by task iscsi_trx/17200 CPU: 0 PID: 17200 Comm: iscsi_trx Not tainted 5.4.0-rc1-dbg+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2011 Call Trace: dump_stack+0x8a/0xd6 print_address_description.constprop.0+0x40/0x60 __kasan_report.cold+0x1b/0x34 kasan_report+0x16/0x20 __asan_load8+0x58/0x90 target_check_reservation+0x171/0x980 [target_core_mod] __target_execute_cmd+0xb1/0xf0 [target_core_mod] target_execute_cmd+0x22d/0x4d0 [target_core_mod] transport_generic_new_cmd+0x31f/0x5b0 [target_core_mod] transport_handle_cdb_direct+0x6f/0x90 [target_core_mod] iscsit_execute_cmd+0x381/0x3f0 [iscsi_target_mod] iscsit_sequence_cmd+0x13b/0x1f0 [iscsi_target_mod] iscsit_process_scsi_cmd+0x4c/0x130 [iscsi_target_mod] iscsit_get_rx_pdu+0x8e8/0x15f0 [iscsi_target_mod] iscsi_target_rx_thread+0x105/0x1b0 [iscsi_target_mod] kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 Allocated by task 1079: save_stack+0x23/0x90 __kasan_kmalloc.constprop.0+0xcf/0xe0 kasan_slab_alloc+0x12/0x20 kmem_cache_alloc+0xfe/0x3a0 transport_alloc_session+0x29/0x80 [target_core_mod] iscsi_target_login_thread+0xceb/0x1920 [iscsi_target_mod] kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 Freed by task 17193: save_stack+0x23/0x90 __kasan_slab_free+0x13a/0x190 kasan_slab_free+0x12/0x20 kmem_cache_free+0xc8/0x3e0 transport_free_session+0x179/0x2f0 [target_core_mod] transport_deregister_session+0x121/0x170 [target_core_mod] iscsit_close_session+0x12c/0x350 [iscsi_target_mod] iscsit_logout_post_handler+0x136/0x380 [iscsi_target_mod] iscsit_response_queue+0x8fa/0xc00 [iscsi_target_mod] iscsi_target_tx_thread+0x28e/0x390 [iscsi_target_mod] kthread+0x1bc/0x210 ret_from_fork+0x24/0x30 The buggy address belongs to the object at ffff88802ecd1860 which belongs to the cache se_sess_cache of size 352 The buggy address is located 24 bytes inside of 352-byte region [ffff88802ecd1860, ffff88802ecd19c0) The buggy address belongs to the page: page:ffffea0000bb3400 refcount:1 mapcount:0 mapping:ffff8880bef2ed00 index:0x0 compound_mapcount: 0 flags: 0x1000000000010200(slab|head) raw: 1000000000010200 dead000000000100 dead000000000122 ffff8880bef2ed00 raw: 0000000000000000 0000000080270027 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88802ecd1700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ecd1780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802ecd1800: fb fb fb fb fc fc fc fc fc fc fc fc fb fb fb fb ^ ffff88802ecd1880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802ecd1900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb Cc: Mike Christie Cc: Roman Bolshakov Signed-off-by: Bart Van Assche Reviewed-by: Roman Bolshakov --- drivers/target/target_core_transport.c | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c index ba7a01bcad7c..09f833c1de8a 100644 --- a/drivers/target/target_core_transport.c +++ b/drivers/target/target_core_transport.c @@ -584,6 +584,15 @@ void transport_free_session(struct se_session *se_sess) } EXPORT_SYMBOL(transport_free_session); +static int target_release_res(struct se_device *dev, void *data) +{ + struct se_session *sess = data; + + if (dev->reservation_holder == sess) + target_release_reservation(dev); + return 0; +} + void transport_deregister_session(struct se_session *se_sess) { struct se_portal_group *se_tpg = se_sess->se_tpg; @@ -600,6 +609,12 @@ void transport_deregister_session(struct se_session *se_sess) se_sess->fabric_sess_ptr = NULL; spin_unlock_irqrestore(&se_tpg->session_lock, flags); + /* + * Since the session is being removed, release SPC-2 + * reservations held by the session that is disappearing. + */ + target_for_each_device(target_release_res, se_sess); + pr_debug("TARGET_CORE[%s]: Deregistered fabric_sess\n", se_tpg->se_tpg_tfo->fabric_name); /*