From patchwork Sat Jan 4 00:20:24 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Brian Masney X-Patchwork-Id: 11317541 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 14B491395 for ; Sat, 4 Jan 2020 00:20:38 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D320124649 for ; Sat, 4 Jan 2020 00:20:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=onstation.org header.i=@onstation.org header.b="LLSCCEs9" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726229AbgADAUh (ORCPT ); Fri, 3 Jan 2020 19:20:37 -0500 Received: from onstation.org ([52.200.56.107]:34346 "EHLO onstation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726697AbgADAUh (ORCPT ); Fri, 3 Jan 2020 19:20:37 -0500 Received: from localhost.localdomain (c-98-239-145-235.hsd1.wv.comcast.net [98.239.145.235]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits)) (No client certificate requested) (Authenticated sender: masneyb) by onstation.org (Postfix) with ESMTPSA id 87D893E9DC; Sat, 4 Jan 2020 00:20:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=onstation.org; s=default; t=1578097236; bh=B+RG3hiGp38Cv0fX6Bwqnm3w4Q+26kJJUHBSvjFw2nQ=; h=From:To:Cc:Subject:Date:From; b=LLSCCEs9ckaThO1hPS756GqAn0/73+gJKZE8FRmSnHW7BJkmgfNU8qttAT01uR/my jsNl1ugSVeqtVGhPNbH3+mEN5Ht7gktgp/FKTY68CbZ2ZrM3lo7TJ+zruWUF751vX8 GWKCkVzs2E1pgBbwF7CbTfZkeWrmg7lpOQeP1VsQ= From: Brian Masney To: robdclark@gmail.com, bjorn.andersson@linaro.org, joro@8bytes.org Cc: agross@kernel.org, iommu@lists.linux-foundation.org, linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org, stephan@gerhold.net, j.neuschaefer@gmx.net Subject: [PATCH v2] iommu/qcom: fix NULL pointer dereference during probe deferral Date: Fri, 3 Jan 2020 19:20:24 -0500 Message-Id: <20200104002024.37335-1-masneyb@onstation.org> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Sender: linux-arm-msm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org When attempting to load the qcom-iommu driver, and an -EPROBE_DEFER error occurs, the following attempted NULL pointer deference occurs: Unable to handle kernel NULL pointer dereference at virtual address 00000014 pgd = (ptrval) [00000014] *pgd=00000000 Internal error: Oops: 5 [#1] PREEMPT SMP ARM Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 5.5.0-rc2-next-20191220-00010-gfb6b8e8bced6-dirty #3 Hardware name: Generic DT based system PC is at qcom_iommu_domain_free (include/linux/pm_runtime.h:226 drivers/iommu/qcom_iommu.c:358) LR is at release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) pc : lr : psr: 60000013 sp : ee89dc48 ip : 00000000 fp : c13a6684 r10: c13a661c r9 : 00000000 r8 : c13a1240 r7 : fffffdfb r6 : 00000000 r5 : edc32f00 r4 : edc32f1c r3 : 00000000 r2 : 00000001 r1 : 00000004 r0 : edc32f1c Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment none Control: 10c5787d Table: 0020406a DAC: 00000051 Process swapper/0 (pid: 1, stack limit = 0x(ptrval)) Stack: (0xee89dc48 to 0xee89e000) dc40: edc3d010 edc37020 00000000 c0316af8 edc3d010 edc37000 dc60: 00000000 c0319684 c14341ac edc3d010 00000000 c083bd88 edc3d010 c13a1240 dc80: c083c2e8 c13a6684 c13a661c c13a6508 c13a661c c083c134 c13a1240 ee89dcec dca0: edc3d010 00000000 ee89dcec c083c2e8 c13a6684 c13a661c c13a6508 c13a661c dcc0: c13a6684 c083a31c c13a6684 ee82a86c edc327b8 c1304e48 edc3d010 00000001 dce0: edc3d054 c083bc08 ee82a880 edc3d010 00000001 c1304e48 edc3d010 edc3d010 dd00: c13a69e8 c083b010 edc3d010 00000000 eea1fc10 c0837aac 00000200 00000000 dd20: 00000000 00000000 00000000 c1304e48 00000000 edc3d000 eea1fc10 00000000 dd40: 00000000 eeff42f4 00000000 00000001 00000000 c09e96e0 eeff42a4 00000000 dd60: 00000000 00000000 eea1fc10 c09e98bc 00000001 eea1fc10 00000000 eea1fc10 dd80: edc32c00 c1391580 eea1fc10 00000001 eea1fc10 c0850f90 c2706dec c14368c0 dda0: 60000013 c1304e48 00000106 eeff42a4 eeff3fa0 00000000 00000000 eea1fc10 ddc0: 00000001 c1248900 00000106 c09e9bd0 00000001 c0c2ee64 eea1fc00 eea1fc10 dde0: eea1fc10 00000000 c13a5b70 00000000 c1248900 c081496c c1023d84 00000000 de00: eeff3fa0 c2706e48 c2706e48 c1304e48 00000001 00000000 eea1fc10 c13a5b70 de20: 00000000 c13a5b70 00000000 c1248900 00000106 c083dfb8 c14341ac eea1fc10 de40: 00000000 c083be58 eea1fc10 c13a5b70 c13a5b70 c13a69e8 c12003ec c123a854 de60: c1248900 c083c134 c1248900 c09e6f3c c0d8d514 eea1fc10 00000000 c13a5b70 de80: c13a69e8 c12003ec c123a854 c1248900 00000106 c083c3e0 00000000 c13a5b70 dea0: eea1fc10 c083c440 00000000 c13a5b70 c083c3e8 c083a23c 00000106 ee82a858 dec0: eea052b4 c1304e48 c13a5b70 edc32b80 00000000 c083b270 c1043084 c121d1d8 dee0: ffffe000 c13a5b70 c121d1d8 ffffe000 00000000 c083cfcc c13ece60 c121d1d8 df00: ffffe000 c0302f90 00000106 c034407c 00000000 c10e3a00 c1044dd0 c12003ec df20: 00000000 00000006 00000006 c0fbecac c0fada88 c0fada3c 00000000 efffcbf8 df40: efffcc0d c1304e48 00000000 00000006 c13f9500 c1304e48 c123a830 00000007 df60: c13f9500 c13f9500 c123a834 c1200f64 00000006 00000006 00000000 c12003ec df80: c0c28194 00000000 c0c28194 00000000 00000000 00000000 00000000 00000000 dfa0: 00000000 c0c2819c 00000000 c03010e8 00000000 00000000 00000000 00000000 dfc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000 dfe0: 00000000 00000000 00000000 00000000 00000013 00000000 00000000 00000000 (qcom_iommu_domain_free) from release_iommu_mapping (arch/arm/mm/dma-mapping.c:2141) (release_iommu_mapping) from arch_teardown_dma_ops (include/linux/dma-mapping.h:271 arch/arm/mm/dma-mapping.c:2335) (arch_teardown_dma_ops) from really_probe (drivers/base/dd.c:607) (really_probe) from driver_probe_device (drivers/base/dd.c:721) (driver_probe_device) from bus_for_each_drv (drivers/base/bus.c:431) (bus_for_each_drv) from __device_attach (drivers/base/dd.c:896) (__device_attach) from bus_probe_device (drivers/base/bus.c:491) (bus_probe_device) from device_add (drivers/base/core.c:2488) (device_add) from of_platform_device_create_pdata (drivers/of/platform.c:189) (of_platform_device_create_pdata) from of_platform_bus_create (drivers/of/platform.c:393 drivers/of/platform.c:346) (of_platform_bus_create) from of_platform_populate (drivers/of/platform.c:486) (of_platform_populate) from msm_pdev_probe (drivers/gpu/drm/msm/msm_drv.c:1197 drivers/gpu/drm/msm/msm_drv.c:1281) (msm_pdev_probe) from platform_drv_probe (drivers/base/platform.c:726) (platform_drv_probe) from really_probe (drivers/base/dd.c:553) (really_probe) from driver_probe_device (drivers/base/dd.c:721) (driver_probe_device) from device_driver_attach (drivers/base/dd.c:995) (device_driver_attach) from __driver_attach (drivers/base/dd.c:1074) (__driver_attach) from bus_for_each_dev (drivers/base/bus.c:304) (bus_for_each_dev) from bus_add_driver (drivers/base/bus.c:623) (bus_add_driver) from driver_register (drivers/base/driver.c:172) (driver_register) from do_one_initcall (include/linux/compiler.h:232 include/linux/jump_label.h:254 include/linux/jump_label.h:264 include/trace/events/initcall.h:48 init/main.c:941) (do_one_initcall) from kernel_init_freeable (init/main.c:1013 init/main.c:1022 init/main.c:1039 init/main.c:1231) (kernel_init_freeable) from kernel_init (init/main.c:1127) (kernel_init) from ret_from_fork (arch/arm/kernel/entry-common.S:156) qcom_iommu_domain_free() has a WARN_ON() that checks to see if the value of iommu is NULL and returns early, so iommu->dev will always be NULL. qcom_iommu_detach_dev() is called prior to freeing the IOMMU domain and is what sets the iommu member to NULL. Let's fix this by adding the 'struct dev' pointer to the qcom_iommu_domain struct. Signed-off-by: Brian Masney Fixes: 0ae349a0f33fb ("iommu/qcom: Add qcom_iommu") Tested-by: Stephan Gerhold Tested-by: Brian Masney --- Changes since v1: - Set CROSS_COMPILE when running scripts/decode_stacktrace.sh. drivers/iommu/qcom_iommu.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/iommu/qcom_iommu.c b/drivers/iommu/qcom_iommu.c index 52f38292df5b..ac4354773c06 100644 --- a/drivers/iommu/qcom_iommu.c +++ b/drivers/iommu/qcom_iommu.c @@ -65,6 +65,7 @@ struct qcom_iommu_domain { struct mutex init_mutex; /* Protects iommu pointer */ struct iommu_domain domain; struct qcom_iommu_dev *iommu; + struct device *dev; }; static struct qcom_iommu_domain *to_qcom_iommu_domain(struct iommu_domain *dom) @@ -243,6 +244,13 @@ static int qcom_iommu_init_domain(struct iommu_domain *domain, }; qcom_domain->iommu = qcom_iommu; + + /* + * This dev pointer is needed to avoid a NULL pointer dereference in + * qcom_iommu_domain_free(). + */ + qcom_domain->dev = qcom_iommu->dev; + pgtbl_ops = alloc_io_pgtable_ops(ARM_32_LPAE_S1, &pgtbl_cfg, fwspec); if (!pgtbl_ops) { dev_err(qcom_iommu->dev, "failed to allocate pagetable ops\n"); @@ -355,11 +363,11 @@ static void qcom_iommu_domain_free(struct iommu_domain *domain) * cannot rely on the device_link. Make sure the IOMMU is on to * avoid unclocked accesses in the TLB inv path: */ - pm_runtime_get_sync(qcom_domain->iommu->dev); + pm_runtime_get_sync(qcom_domain->dev); free_io_pgtable_ops(qcom_domain->pgtbl_ops); - pm_runtime_put_sync(qcom_domain->iommu->dev); + pm_runtime_put_sync(qcom_domain->dev); kfree(qcom_domain); }