From patchwork Thu Sep 24 06:59:45 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mansur Alisha Shaik X-Patchwork-Id: 11796389 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 3216659D for ; Thu, 24 Sep 2020 07:00:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 1B60F2395C for ; Thu, 24 Sep 2020 07:00:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727061AbgIXG75 (ORCPT ); Thu, 24 Sep 2020 02:59:57 -0400 Received: from alexa-out.qualcomm.com ([129.46.98.28]:27029 "EHLO alexa-out.qualcomm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726902AbgIXG7z (ORCPT ); Thu, 24 Sep 2020 02:59:55 -0400 Received: from ironmsg07-lv.qualcomm.com (HELO ironmsg07-lv.qulacomm.com) ([10.47.202.151]) by alexa-out.qualcomm.com with ESMTP; 23 Sep 2020 23:59:55 -0700 Received: from ironmsg02-blr.qualcomm.com ([10.86.208.131]) by ironmsg07-lv.qulacomm.com with ESMTP/TLS/AES256-SHA; 23 Sep 2020 23:59:53 -0700 Received: from c-mansur-linux.qualcomm.com ([10.204.90.208]) by ironmsg02-blr.qualcomm.com with ESMTP; 24 Sep 2020 12:29:52 +0530 Received: by c-mansur-linux.qualcomm.com (Postfix, from userid 461723) id 584B621D5B; Thu, 24 Sep 2020 12:29:51 +0530 (IST) From: Mansur Alisha Shaik To: linux-media@vger.kernel.org, stanimir.varbanov@linaro.org Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, vgarodia@codeaurora.org, Mansur Alisha Shaik Subject: [PATCH v5 2/3] venus: handle use after free for iommu_map/iommu_unmap Date: Thu, 24 Sep 2020 12:29:45 +0530 Message-Id: <1600930786-18275-3-git-send-email-mansur@codeaurora.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1600930786-18275-1-git-send-email-mansur@codeaurora.org> References: <1600930786-18275-1-git-send-email-mansur@codeaurora.org> Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org In concurrency usecase and reboot scenario we are seeing muliple crashes related to iommu_map/iommu_unamp of core->fw.iommu_domain. In one case we are seeing "Unable to handle kernel NULL pointer dereference at virtual address 0000000000000008" crash, this is because of core->fw.iommu_domain in venus_firmware_deinit() and trying to map in venus_boot() during venus_sys_error_handler() Call trace: __iommu_map+0x4c/0x348 iommu_map+0x5c/0x70 venus_boot+0x184/0x230 [venus_core] venus_sys_error_handler+0xa0/0x14c [venus_core] process_one_work+0x210/0x3d0 worker_thread+0x248/0x3f4 kthread+0x11c/0x12c ret_from_fork+0x10/0x18 In second case we are seeing "Unable to handle kernel paging request at virtual address 006b6b6b6b6b6b9b" crash, this is because of unmapping iommu domain which is already unmapped. Call trace: venus_remove+0xf8/0x108 [venus_core] venus_core_shutdown+0x1c/0x34 [venus_core] platform_drv_shutdown+0x28/0x34 device_shutdown+0x154/0x1fc kernel_restart_prepare+0x40/0x4c kernel_restart+0x1c/0x64 __arm64_sys_reboot+0x190/0x238 el0_svc_common+0xa4/0x154 el0_svc_compat_handler+0x2c/0x38 el0_svc_compat+0x8/0x10 Signed-off-by: Mansur Alisha Shaik --- drivers/media/platform/qcom/venus/firmware.c | 17 +++++++++++++---- 1 file changed, 13 insertions(+), 4 deletions(-) diff --git a/drivers/media/platform/qcom/venus/firmware.c b/drivers/media/platform/qcom/venus/firmware.c index 1db64a8..d03e2dd 100644 --- a/drivers/media/platform/qcom/venus/firmware.c +++ b/drivers/media/platform/qcom/venus/firmware.c @@ -171,9 +171,14 @@ static int venus_shutdown_no_tz(struct venus_core *core) iommu = core->fw.iommu_domain; - unmapped = iommu_unmap(iommu, VENUS_FW_START_ADDR, mapped); - if (unmapped != mapped) - dev_err(dev, "failed to unmap firmware\n"); + if (core->fw.mapped_mem_size && iommu) { + unmapped = iommu_unmap(iommu, VENUS_FW_START_ADDR, mapped); + + if (unmapped != mapped) + dev_err(dev, "failed to unmap firmware\n"); + else + core->fw.mapped_mem_size = 0; + } return 0; } @@ -305,7 +310,11 @@ void venus_firmware_deinit(struct venus_core *core) iommu = core->fw.iommu_domain; iommu_detach_device(iommu, core->fw.dev); - iommu_domain_free(iommu); + + if (core->fw.iommu_domain) { + iommu_domain_free(iommu); + core->fw.iommu_domain = NULL; + } platform_device_unregister(to_platform_device(core->fw.dev)); }