Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933803AbeALA4Q (ORCPT + 1 other); Thu, 11 Jan 2018 19:56:16 -0500 Received: from mga04.intel.com ([192.55.52.120]:8599 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933761AbeALA4M (ORCPT ); Thu, 11 Jan 2018 19:56:12 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.46,346,1511856000"; d="scan'208";a="19445656" Subject: [PATCH v2 17/19] qla2xxx: prevent bounds-check bypass via speculative execution From: Dan Williams To: linux-kernel@vger.kernel.org Cc: linux-arch@vger.kernel.org, "James E.J. Bottomley" , "Martin K. Petersen" , linux-scsi@vger.kernel.org, kernel-hardening@lists.openwall.com, qla2xxx-upstream@qlogic.com, tglx@linutronix.de, torvalds@linux-foundation.org, akpm@linux-foundation.org, Elena Reshetova , alan@linux.intel.com Date: Thu, 11 Jan 2018 16:47:57 -0800 Message-ID: <151571807774.27429.7382333750792304971.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <151571798296.27429.7166552848688034184.stgit@dwillia2-desk3.amr.corp.intel.com> References: <151571798296.27429.7166552848688034184.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.17.1-9-g687f MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Return-Path: Static analysis reports that 'handle' may be a user controlled value that is used as a data dependency to read 'sp' from the 'req->outstanding_cmds' array. In order to avoid potential leaks of kernel memory values, block speculative execution of the instruction stream that could issue reads based on an invalid value of 'sp'. In this case 'sp' is directly dereferenced later in the function. If completion tags can be specified by userspace or otherwise controlled, we should sanitize 'handle' with array_ptr. Based on an original patch by Elena Reshetova. Cc: qla2xxx-upstream@qlogic.com Cc: "James E.J. Bottomley" Cc: "Martin K. Petersen" Cc: linux-scsi@vger.kernel.org Signed-off-by: Elena Reshetova Signed-off-by: Dan Williams --- drivers/scsi/qla2xxx/qla_mr.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/scsi/qla2xxx/qla_mr.c b/drivers/scsi/qla2xxx/qla_mr.c index d5da3981cefe..6de3f0fddcfc 100644 --- a/drivers/scsi/qla2xxx/qla_mr.c +++ b/drivers/scsi/qla2xxx/qla_mr.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -2275,7 +2276,7 @@ qlafx00_ioctl_iosb_entry(scsi_qla_host_t *vha, struct req_que *req, static void qlafx00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt) { - srb_t *sp; + srb_t *sp, **elem; fc_port_t *fcport; struct scsi_cmnd *cp; struct sts_entry_fx00 *sts; @@ -2304,8 +2305,10 @@ qlafx00_status_entry(scsi_qla_host_t *vha, struct rsp_que *rsp, void *pkt) req = ha->req_q_map[que]; /* Validate handle. */ - if (handle < req->num_outstanding_cmds) - sp = req->outstanding_cmds[handle]; + elem = array_ptr(req->outstanding_cmds, handle, + req->num_outstanding_cmds); + if (elem) + sp = *elem; else sp = NULL; @@ -2626,7 +2629,7 @@ static void qlafx00_multistatus_entry(struct scsi_qla_host *vha, struct rsp_que *rsp, void *pkt) { - srb_t *sp; + srb_t *sp, **elem; struct multi_sts_entry_fx00 *stsmfx; struct qla_hw_data *ha = vha->hw; uint32_t handle, hindex, handle_count, i; @@ -2655,8 +2658,10 @@ qlafx00_multistatus_entry(struct scsi_qla_host *vha, req = ha->req_q_map[que]; /* Validate handle. */ - if (handle < req->num_outstanding_cmds) - sp = req->outstanding_cmds[handle]; + elem = array_ptr(req->outstanding_cmds, handle, + req->num_outstanding_cmds); + if (elem) + sp = *elem; else sp = NULL;