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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A65B6C433FE for ; Mon, 24 Jan 2022 19:15:44 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234328AbiAXTPm (ORCPT ); Mon, 24 Jan 2022 14:15:42 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47518 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347546AbiAXTNQ (ORCPT ); Mon, 24 Jan 2022 14:13:16 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [IPv6:2604:1380:4601:e00::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id AFBF0C08EAD7; Mon, 24 Jan 2022 11:04:39 -0800 (PST) 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 ams.source.kernel.org (Postfix) with ESMTPS id EBD0AB8122C; Mon, 24 Jan 2022 19:04:36 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 10C43C340E5; Mon, 24 Jan 2022 19:04:34 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1643051075; bh=0HIcbNe44vpoX7J0z4B6yzMybdVKFNuIc5+ehR4MREA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Dqe0YPy2/nNvs/0MSNjx/pstIJMp3UtuJM7xeCHBFmksPhavbDIpddy7qkd4YnvBp lnTPk9C/73HKAVHJCewEl6z+skuz6Y344rFCFjHYNagsRB4RC1l5v6JNMVg/PkF8Uv lYugf+yg7B0vsY8ihCaT0qgwbZExs0bFtcQ4p27Q= From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, =?UTF-8?q?Christian=20K=C3=B6nig?= , Zhou Qingyang , Alex Deucher , Sasha Levin Subject: [PATCH 4.14 047/186] drm/radeon/radeon_kms: Fix a NULL pointer dereference in radeon_driver_open_kms() Date: Mon, 24 Jan 2022 19:42:02 +0100 Message-Id: <20220124183938.643797389@linuxfoundation.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20220124183937.101330125@linuxfoundation.org> References: <20220124183937.101330125@linuxfoundation.org> User-Agent: quilt/0.66 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org From: Zhou Qingyang [ Upstream commit ab50cb9df8896b39aae65c537a30de2c79c19735 ] In radeon_driver_open_kms(), radeon_vm_bo_add() is assigned to vm->ib_bo_va and passes and used in radeon_vm_bo_set_addr(). In radeon_vm_bo_set_addr(), there is a dereference of vm->ib_bo_va, which could lead to a NULL pointer dereference on failure of radeon_vm_bo_add(). Fix this bug by adding a check of vm->ib_bo_va. This bug was found by a static analyzer. The analysis employs differential checking to identify inconsistent security operations (e.g., checks or kfrees) between two code paths and confirms that the inconsistent operations are not recovered in the current function or the callers, so they constitute bugs. Note that, as a bug found by static analysis, it can be a false positive or hard to trigger. Multiple researchers have cross-reviewed the bug. Builds with CONFIG_DRM_RADEON=m show no new warnings, and our static analyzer no longer warns about this code. Fixes: cc9e67e3d700 ("drm/radeon: fix VM IB handling") Reviewed-by: Christian König Signed-off-by: Zhou Qingyang Signed-off-by: Alex Deucher Signed-off-by: Sasha Levin --- drivers/gpu/drm/radeon/radeon_kms.c | 36 ++++++++++++++++------------- 1 file changed, 20 insertions(+), 16 deletions(-) diff --git a/drivers/gpu/drm/radeon/radeon_kms.c b/drivers/gpu/drm/radeon/radeon_kms.c index 4973bd241aec3..fb292b9f3d402 100644 --- a/drivers/gpu/drm/radeon/radeon_kms.c +++ b/drivers/gpu/drm/radeon/radeon_kms.c @@ -655,6 +655,8 @@ void radeon_driver_lastclose_kms(struct drm_device *dev) int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv) { struct radeon_device *rdev = dev->dev_private; + struct radeon_fpriv *fpriv; + struct radeon_vm *vm; int r; file_priv->driver_priv = NULL; @@ -667,8 +669,6 @@ int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv) /* new gpu have virtual address space support */ if (rdev->family >= CHIP_CAYMAN) { - struct radeon_fpriv *fpriv; - struct radeon_vm *vm; fpriv = kzalloc(sizeof(*fpriv), GFP_KERNEL); if (unlikely(!fpriv)) { @@ -679,35 +679,39 @@ int radeon_driver_open_kms(struct drm_device *dev, struct drm_file *file_priv) if (rdev->accel_working) { vm = &fpriv->vm; r = radeon_vm_init(rdev, vm); - if (r) { - kfree(fpriv); - goto out_suspend; - } + if (r) + goto out_fpriv; r = radeon_bo_reserve(rdev->ring_tmp_bo.bo, false); - if (r) { - radeon_vm_fini(rdev, vm); - kfree(fpriv); - goto out_suspend; - } + if (r) + goto out_vm_fini; /* map the ib pool buffer read only into * virtual address space */ vm->ib_bo_va = radeon_vm_bo_add(rdev, vm, rdev->ring_tmp_bo.bo); + if (!vm->ib_bo_va) { + r = -ENOMEM; + goto out_vm_fini; + } + r = radeon_vm_bo_set_addr(rdev, vm->ib_bo_va, RADEON_VA_IB_OFFSET, RADEON_VM_PAGE_READABLE | RADEON_VM_PAGE_SNOOPED); - if (r) { - radeon_vm_fini(rdev, vm); - kfree(fpriv); - goto out_suspend; - } + if (r) + goto out_vm_fini; } file_priv->driver_priv = fpriv; } + if (!r) + goto out_suspend; + +out_vm_fini: + radeon_vm_fini(rdev, vm); +out_fpriv: + kfree(fpriv); out_suspend: pm_runtime_mark_last_busy(dev->dev); pm_runtime_put_autosuspend(dev->dev); -- 2.34.1