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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS 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 5C0BDC43218 for ; Sat, 27 Apr 2019 15:32:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37B3F206A3 for ; Sat, 27 Apr 2019 15:32:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728741AbfD0PcH (ORCPT ); Sat, 27 Apr 2019 11:32:07 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:60750 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726791AbfD0PPM (ORCPT ); Sat, 27 Apr 2019 11:15:12 -0400 Received: from [192.168.4.242] (helo=deadeye) by shadbolt.decadent.org.uk with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.89) (envelope-from ) id 1hKP2j-0000z8-WD; Sat, 27 Apr 2019 16:15:10 +0100 Received: from ben by deadeye with local (Exim 4.92) (envelope-from ) id 1hKP2h-0004PK-K2; Sat, 27 Apr 2019 16:15:07 +0100 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, Denis Kirjanov , "Jeff Moyer" , "Artur Paszkiewicz" , "James E.J. Bottomley" , "Christoph Hellwig" , "Martin K. Petersen" , "Intel SCU Linux support" , "Logan Gunthorpe" , "Jens Axboe" Date: Sat, 27 Apr 2019 16:13:09 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) X-Patchwork-Hint: ignore Subject: [PATCH 3.16 022/202] scsi: isci: initialize shost fully before calling scsi_add_host() In-Reply-To: X-SA-Exim-Connect-IP: 192.168.4.242 X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.66-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Logan Gunthorpe commit cc29a1b0a3f2597ce887d339222fa85b9307706d upstream. scsi_mq_setup_tags(), which is called by scsi_add_host(), calculates the command size to allocate based on the prot_capabilities. In the isci driver, scsi_host_set_prot() is called after scsi_add_host() so the command size gets calculated to be smaller than it needs to be. Eventually, scsi_mq_init_request() locates the 'prot_sdb' after the command assuming it was sized correctly and a buffer overrun may occur. However, seeing blk_mq_alloc_rqs() rounds up to the nearest cache line size, the mistake can go unnoticed. The bug was noticed after the struct request size was reduced by commit 9d037ad707ed ("block: remove req->timeout_list") Which likely reduced the allocated space for the request by an entire cache line, enough that the overflow could be hit and it caused a panic, on boot, at: RIP: 0010:t10_pi_complete+0x77/0x1c0 Call Trace: sd_done+0xf5/0x340 scsi_finish_command+0xc3/0x120 blk_done_softirq+0x83/0xb0 __do_softirq+0xa1/0x2e6 irq_exit+0xbc/0xd0 call_function_single_interrupt+0xf/0x20 sd_done() would call scsi_prot_sg_count() which reads the number of entities in 'prot_sdb', but seeing 'prot_sdb' is located after the end of the allocated space it reads a garbage number and erroneously calls t10_pi_complete(). To prevent this, the calls to scsi_host_set_prot() are moved into isci_host_alloc() before the call to scsi_add_host(). Out of caution, also move the similar call to scsi_host_set_guard(). Fixes: 3d2d75254915 ("[SCSI] isci: T10 DIF support") Link: http://lkml.kernel.org/r/da851333-eadd-163a-8c78-e1f4ec5ec857@deltatee.com Signed-off-by: Logan Gunthorpe Cc: Intel SCU Linux support Cc: Artur Paszkiewicz Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: Christoph Hellwig Cc: Jens Axboe Cc: Jeff Moyer Reviewed-by: Jeff Moyer Reviewed-by: Jens Axboe Signed-off-by: Martin K. Petersen Signed-off-by: Ben Hutchings --- drivers/scsi/isci/init.c | 14 +++++++------- 1 file changed, 7 insertions(+), 7 deletions(-) --- a/drivers/scsi/isci/init.c +++ b/drivers/scsi/isci/init.c @@ -598,6 +598,13 @@ static struct isci_host *isci_host_alloc shost->max_lun = ~0; shost->max_cmd_len = MAX_COMMAND_SIZE; + /* turn on DIF support */ + scsi_host_set_prot(shost, + SHOST_DIF_TYPE1_PROTECTION | + SHOST_DIF_TYPE2_PROTECTION | + SHOST_DIF_TYPE3_PROTECTION); + scsi_host_set_guard(shost, SHOST_DIX_GUARD_CRC); + err = scsi_add_host(shost, &pdev->dev); if (err) goto err_shost; @@ -685,13 +692,6 @@ static int isci_pci_probe(struct pci_dev goto err_host_alloc; } pci_info->hosts[i] = h; - - /* turn on DIF support */ - scsi_host_set_prot(to_shost(h), - SHOST_DIF_TYPE1_PROTECTION | - SHOST_DIF_TYPE2_PROTECTION | - SHOST_DIF_TYPE3_PROTECTION); - scsi_host_set_guard(to_shost(h), SHOST_DIX_GUARD_CRC); } err = isci_setup_interrupts(pdev);