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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,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 63619C433E9 for ; Fri, 15 Jan 2021 12:31:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 327F6238A0 for ; Fri, 15 Jan 2021 12:31:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732254AbhAOMau (ORCPT ); Fri, 15 Jan 2021 07:30:50 -0500 Received: from mail.kernel.org ([198.145.29.99]:36470 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732214AbhAOMat (ORCPT ); Fri, 15 Jan 2021 07:30:49 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2976223370; Fri, 15 Jan 2021 12:29:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1610713788; bh=ZuQboh6gdy7fBB0NZFtfHFJ+8D8Z+kY0IYsRUmcNjSA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=qrX3dWiS0juzX/82VkadiqwBdOnwzH3YMJ962ncv8mYIp3++pYrq39GfkquZUxWUu s2JecdshOYssUzdAJwSx9GjNM6tCTdtoweESCmX72KWmWLO/+QWe5Q6E04psYSFn/S VaxK9B50DOkI6nckq7lVdD5j7aFD0oVY+9B4IRbs= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Lee Duncan , David Disseldorp , Mike Christie , "Martin K. Petersen" , Sasha Levin Subject: [PATCH 4.4 06/18] scsi: target: Fix XCOPY NAA identifier lookup Date: Fri, 15 Jan 2021 13:27:34 +0100 Message-Id: <20210115121955.423464201@linuxfoundation.org> X-Mailer: git-send-email 2.30.0 In-Reply-To: <20210115121955.112329537@linuxfoundation.org> References: <20210115121955.112329537@linuxfoundation.org> User-Agent: quilt/0.66 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: David Disseldorp [ Upstream commit 2896c93811e39d63a4d9b63ccf12a8fbc226e5e4 ] When attempting to match EXTENDED COPY CSCD descriptors with corresponding se_devices, target_xcopy_locate_se_dev_e4() currently iterates over LIO's global devices list which includes all configured backstores. This change ensures that only initiator-accessible backstores are considered during CSCD descriptor lookup, according to the session's se_node_acl LUN list. To avoid LUN removal race conditions, device pinning is changed from being configfs based to instead using the se_node_acl lun_ref. Reference: CVE-2020-28374 Fixes: cbf031f425fd ("target: Add support for EXTENDED_COPY copy offload emulation") Reviewed-by: Lee Duncan Signed-off-by: David Disseldorp Signed-off-by: Mike Christie Signed-off-by: Martin K. Petersen Signed-off-by: Sasha Levin --- drivers/target/target_core_xcopy.c | 119 +++++++++++++++++------------ drivers/target/target_core_xcopy.h | 1 + 2 files changed, 71 insertions(+), 49 deletions(-) diff --git a/drivers/target/target_core_xcopy.c b/drivers/target/target_core_xcopy.c index b0e8f432c7205..9587375122295 100644 --- a/drivers/target/target_core_xcopy.c +++ b/drivers/target/target_core_xcopy.c @@ -52,60 +52,83 @@ static int target_xcopy_gen_naa_ieee(struct se_device *dev, unsigned char *buf) return 0; } -struct xcopy_dev_search_info { - const unsigned char *dev_wwn; - struct se_device *found_dev; -}; - +/** + * target_xcopy_locate_se_dev_e4_iter - compare XCOPY NAA device identifiers + * + * @se_dev: device being considered for match + * @dev_wwn: XCOPY requested NAA dev_wwn + * @return: 1 on match, 0 on no-match + */ static int target_xcopy_locate_se_dev_e4_iter(struct se_device *se_dev, - void *data) + const unsigned char *dev_wwn) { - struct xcopy_dev_search_info *info = data; unsigned char tmp_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN]; int rc; - if (!se_dev->dev_attrib.emulate_3pc) + if (!se_dev->dev_attrib.emulate_3pc) { + pr_debug("XCOPY: emulate_3pc disabled on se_dev %p\n", se_dev); return 0; + } memset(&tmp_dev_wwn[0], 0, XCOPY_NAA_IEEE_REGEX_LEN); target_xcopy_gen_naa_ieee(se_dev, &tmp_dev_wwn[0]); - rc = memcmp(&tmp_dev_wwn[0], info->dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN); - if (rc != 0) - return 0; - - info->found_dev = se_dev; - pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev); - - rc = target_depend_item(&se_dev->dev_group.cg_item); + rc = memcmp(&tmp_dev_wwn[0], dev_wwn, XCOPY_NAA_IEEE_REGEX_LEN); if (rc != 0) { - pr_err("configfs_depend_item attempt failed: %d for se_dev: %p\n", - rc, se_dev); - return rc; + pr_debug("XCOPY: skip non-matching: %*ph\n", + XCOPY_NAA_IEEE_REGEX_LEN, tmp_dev_wwn); + return 0; } + pr_debug("XCOPY 0xe4: located se_dev: %p\n", se_dev); - pr_debug("Called configfs_depend_item for se_dev: %p se_dev->se_dev_group: %p\n", - se_dev, &se_dev->dev_group); return 1; } -static int target_xcopy_locate_se_dev_e4(const unsigned char *dev_wwn, - struct se_device **found_dev) +static int target_xcopy_locate_se_dev_e4(struct se_session *sess, + const unsigned char *dev_wwn, + struct se_device **_found_dev, + struct percpu_ref **_found_lun_ref) { - struct xcopy_dev_search_info info; - int ret; - - memset(&info, 0, sizeof(info)); - info.dev_wwn = dev_wwn; - - ret = target_for_each_device(target_xcopy_locate_se_dev_e4_iter, &info); - if (ret == 1) { - *found_dev = info.found_dev; - return 0; - } else { - pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n"); - return -EINVAL; + struct se_dev_entry *deve; + struct se_node_acl *nacl; + struct se_lun *this_lun = NULL; + struct se_device *found_dev = NULL; + + /* cmd with NULL sess indicates no associated $FABRIC_MOD */ + if (!sess) + goto err_out; + + pr_debug("XCOPY 0xe4: searching for: %*ph\n", + XCOPY_NAA_IEEE_REGEX_LEN, dev_wwn); + + nacl = sess->se_node_acl; + rcu_read_lock(); + hlist_for_each_entry_rcu(deve, &nacl->lun_entry_hlist, link) { + struct se_device *this_dev; + int rc; + + this_lun = rcu_dereference(deve->se_lun); + this_dev = rcu_dereference_raw(this_lun->lun_se_dev); + + rc = target_xcopy_locate_se_dev_e4_iter(this_dev, dev_wwn); + if (rc) { + if (percpu_ref_tryget_live(&this_lun->lun_ref)) + found_dev = this_dev; + break; + } } + rcu_read_unlock(); + if (found_dev == NULL) + goto err_out; + + pr_debug("lun_ref held for se_dev: %p se_dev->se_dev_group: %p\n", + found_dev, &found_dev->dev_group); + *_found_dev = found_dev; + *_found_lun_ref = &this_lun->lun_ref; + return 0; +err_out: + pr_debug_ratelimited("Unable to locate 0xe4 descriptor for EXTENDED_COPY\n"); + return -EINVAL; } static int target_xcopy_parse_tiddesc_e4(struct se_cmd *se_cmd, struct xcopy_op *xop, @@ -248,12 +271,16 @@ static int target_xcopy_parse_target_descriptors(struct se_cmd *se_cmd, switch (xop->op_origin) { case XCOL_SOURCE_RECV_OP: - rc = target_xcopy_locate_se_dev_e4(xop->dst_tid_wwn, - &xop->dst_dev); + rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess, + xop->dst_tid_wwn, + &xop->dst_dev, + &xop->remote_lun_ref); break; case XCOL_DEST_RECV_OP: - rc = target_xcopy_locate_se_dev_e4(xop->src_tid_wwn, - &xop->src_dev); + rc = target_xcopy_locate_se_dev_e4(se_cmd->se_sess, + xop->src_tid_wwn, + &xop->src_dev, + &xop->remote_lun_ref); break; default: pr_err("XCOPY CSCD descriptor IDs not found in CSCD list - " @@ -397,18 +424,12 @@ static int xcopy_pt_get_cmd_state(struct se_cmd *se_cmd) static void xcopy_pt_undepend_remotedev(struct xcopy_op *xop) { - struct se_device *remote_dev; - if (xop->op_origin == XCOL_SOURCE_RECV_OP) - remote_dev = xop->dst_dev; + pr_debug("putting dst lun_ref for %p\n", xop->dst_dev); else - remote_dev = xop->src_dev; - - pr_debug("Calling configfs_undepend_item for" - " remote_dev: %p remote_dev->dev_group: %p\n", - remote_dev, &remote_dev->dev_group.cg_item); + pr_debug("putting src lun_ref for %p\n", xop->src_dev); - target_undepend_item(&remote_dev->dev_group.cg_item); + percpu_ref_put(xop->remote_lun_ref); } static void xcopy_pt_release_cmd(struct se_cmd *se_cmd) diff --git a/drivers/target/target_core_xcopy.h b/drivers/target/target_core_xcopy.h index 700a981c7b415..7db8d0c9223f8 100644 --- a/drivers/target/target_core_xcopy.h +++ b/drivers/target/target_core_xcopy.h @@ -19,6 +19,7 @@ struct xcopy_op { struct se_device *dst_dev; unsigned char dst_tid_wwn[XCOPY_NAA_IEEE_REGEX_LEN]; unsigned char local_dev_wwn[XCOPY_NAA_IEEE_REGEX_LEN]; + struct percpu_ref *remote_lun_ref; sector_t src_lba; sector_t dst_lba; -- 2.27.0