From patchwork Tue Apr 4 19:23:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jiri Kosina X-Patchwork-Id: 670716 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 61F2AC761A6 for ; Tue, 4 Apr 2023 19:24:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235157AbjDDTX7 (ORCPT ); Tue, 4 Apr 2023 15:23:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50574 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230080AbjDDTX5 (ORCPT ); Tue, 4 Apr 2023 15:23:57 -0400 Received: from dfw.source.kernel.org (dfw.source.kernel.org [IPv6:2604:1380:4641:c500::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C934810E5; Tue, 4 Apr 2023 12:23:56 -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 dfw.source.kernel.org (Postfix) with ESMTPS id 6E1B163902; Tue, 4 Apr 2023 19:23:56 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 484FBC433EF; Tue, 4 Apr 2023 19:23:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1680636235; bh=OuMl4MZe4WJtRSbESB4JIV0giVD3UlgbBluQ/2Sz5/M=; h=Date:From:To:cc:Subject:From; b=bPNdwAnQg9PHrMv6WoZ+5Qcjxn4OTon6Khg3X2n6gCdj/yNXN8cfK72oh3xkyFtiK MNoViqdTkzOQzRX8nYwMxtBsRCbRMjYyKE4vTnmC/X4dV2rtvUwvPQEp+RnS1aYN29 Qao5Y2UwD1hibOjqMXhcUwm/ZonVf29ZT8M9PQGeLEtx8V7V4BRQ1tFBu7bVULVXD3 VWlmf34u/sZHm435VMSjT9H72y0l9Sh5p+u4i8yPWlaTYNPN7cPH0nIhDK0N9iIIeJ IxVq2tz2FNZW7VUW9NcLiOZi+1mravSCFcfa0XdqhfI08QBKLUBB4UfzDhRJbleEUx eMS8ELdb+9fTw== Date: Tue, 4 Apr 2023 21:23:42 +0200 (CEST) From: Jiri Kosina To: "James E.J. Bottomley" , "Martin K. Petersen" cc: linux-scsi@vger.kernel.org, linux-kernel@vger.kernel.org, Ding Hui , Michal Kolar Subject: [PATCH] scsi: ses: Handle enclosure with just a primary component gracefully Message-ID: User-Agent: Alpine 2.21 (LSU 202 2017-01-01) MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org From: Jiri Kosina This reverts 3fe97ff3d9493 ("scsi: ses: Don't attach if enclosure has no components") and introduces proper handling of case where there are no detected secondary components, but primary component (enumerated in num_enclosures) does exist. That fix was originally proposed by Ding Hui . Completely ignoring devices that have one primary enclosure and no secondary one results in ses_intf_add() bailing completely scsi 2:0:0:254: enclosure has no enumerated components scsi 2:0:0:254: Failed to bind enclosure -12ven in valid configurations such even on valid configurations with 1 primary and 0 secondary enclosures as below: # sg_ses /dev/sg0 3PARdata SES 3321 Supported diagnostic pages: Supported Diagnostic Pages [sdp] [0x0] Configuration (SES) [cf] [0x1] Short Enclosure Status (SES) [ses] [0x8] # sg_ses -p cf /dev/sg0 3PARdata SES 3321 Configuration diagnostic page: number of secondary subenclosures: 0 generation code: 0x0 enclosure descriptor list Subenclosure identifier: 0 [primary] relative ES process id: 0, number of ES processes: 1 number of type descriptor headers: 1 enclosure logical identifier (hex): 20000002ac02068d enclosure vendor: 3PARdata product: VV rev: 3321 type descriptor header and text list Element type: Unspecified, subenclosure id: 0 number of possible elements: 1 The changelog for the original fix follows ===== We can get a crash when disconnecting the iSCSI session, the call trace like this: [ffff00002a00fb70] kfree at ffff00000830e224 [ffff00002a00fba0] ses_intf_remove at ffff000001f200e4 [ffff00002a00fbd0] device_del at ffff0000086b6a98 [ffff00002a00fc50] device_unregister at ffff0000086b6d58 [ffff00002a00fc70] __scsi_remove_device at ffff00000870608c [ffff00002a00fca0] scsi_remove_device at ffff000008706134 [ffff00002a00fcc0] __scsi_remove_target at ffff0000087062e4 [ffff00002a00fd10] scsi_remove_target at ffff0000087064c0 [ffff00002a00fd70] __iscsi_unbind_session at ffff000001c872c4 [ffff00002a00fdb0] process_one_work at ffff00000810f35c [ffff00002a00fe00] worker_thread at ffff00000810f648 [ffff00002a00fe70] kthread at ffff000008116e98 In ses_intf_add, components count could be 0, and kcalloc 0 size scomp, but not saved in edev->component[i].scratch In this situation, edev->component[0].scratch is an invalid pointer, when kfree it in ses_intf_remove_enclosure, a crash like above would happen The call trace also could be other random cases when kfree cannot catch the invalid pointer We should not use edev->component[] array when the components count is 0 We also need check index when use edev->component[] array in ses_enclosure_data_process ===== Reported-by: Michal Kolar Originally-by: Ding Hui Cc: stable@vger.kernel.org Fixes: 3fe97ff3d9493 ("scsi: ses: Don't attach if enclosure has no components") Signed-off-by: Jiri Kosina --- drivers/scsi/ses.c | 20 ++++++++------------ 1 file changed, 8 insertions(+), 12 deletions(-) diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c index b11a9162e73a..b54f2c6c08c3 100644 --- a/drivers/scsi/ses.c +++ b/drivers/scsi/ses.c @@ -509,9 +509,6 @@ static int ses_enclosure_find_by_addr(struct enclosure_device *edev, int i; struct ses_component *scomp; - if (!edev->component[0].scratch) - return 0; - for (i = 0; i < edev->components; i++) { scomp = edev->component[i].scratch; if (scomp->addr != efd->addr) @@ -602,8 +599,10 @@ static void ses_enclosure_data_process(struct enclosure_device *edev, components++, type_ptr[0], name); - else + else if (components < edev->components) ecomp = &edev->component[components++]; + else + ecomp = ERR_PTR(-EINVAL); if (!IS_ERR(ecomp)) { if (addl_desc_ptr) { @@ -734,11 +733,6 @@ static int ses_intf_add(struct device *cdev, components += type_ptr[1]; } - if (components == 0) { - sdev_printk(KERN_WARNING, sdev, "enclosure has no enumerated components\n"); - goto err_free; - } - ses_dev->page1 = buf; ses_dev->page1_len = len; buf = NULL; @@ -780,9 +774,11 @@ static int ses_intf_add(struct device *cdev, buf = NULL; } page2_not_supported: - scomp = kcalloc(components, sizeof(struct ses_component), GFP_KERNEL); - if (!scomp) - goto err_free; + if (components > 0) { + scomp = kcalloc(components, sizeof(struct ses_component), GFP_KERNEL); + if (!scomp) + goto err_free; + } edev = enclosure_register(cdev->parent, dev_name(&sdev->sdev_gendev), components, &ses_enclosure_callbacks);