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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 19219C28B28 for ; Wed, 12 Mar 2025 21:04:58 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id D001210E7AC; Wed, 12 Mar 2025 21:04:57 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=intel.com header.i=@intel.com header.b="lZ0F9bqD"; dkim-atps=neutral Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.15]) by gabe.freedesktop.org (Postfix) with ESMTPS id 0CBCF10E7A9; Wed, 12 Mar 2025 21:04:56 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1741813497; x=1773349497; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=XyD9AP1tNEBR9EtZyXgTn9w2JTabbGJ6HBZQblevDw8=; b=lZ0F9bqD2+1i29x0ozg3FCRThxFERMi6B3uPgRSChFXPnq4CrDqoQ/Rk zujGemXse3xYMM0EtFALxg9mWG+xK+zep5caLxHRIXjCa5nPax1+3mSsk Hb2+3B5JcvnNALGqnfAprCWZ3kVsnF35ezuC599suLQcQEROK2kBeolxa F33Qr+VH8uBYAoKpiTg0BFhz+tdwy0q2Nj2X0pXRWP1528DNPXbR2c6O/ BsT80Zoc4HZq028WJZuKT0ogyXN7dJhtBwRoV8/zFsrFtiv4Gi+rHP1iG 49pWFfsxNjM5fWqzACO6tiO/Xx4R0bvdDm/X8+QhNPkuftZrQIq86UtLM g==; X-CSE-ConnectionGUID: g7xeuJSgSbCsG8EC+AHDAw== X-CSE-MsgGUID: ThFgsfcaTB25eHor+C+MTg== X-IronPort-AV: E=McAfee;i="6700,10204,11371"; a="46562125" X-IronPort-AV: E=Sophos;i="6.14,242,1736841600"; d="scan'208";a="46562125" Received: from fmviesa007.fm.intel.com ([10.60.135.147]) by orvoesa107.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Mar 2025 14:04:56 -0700 X-CSE-ConnectionGUID: VT4MA3OIS3eh8ITamcBxhQ== X-CSE-MsgGUID: ssyW5HIZRNmvqgAUhyX3Dg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.14,242,1736841600"; d="scan'208";a="120791046" Received: from klitkey1-mobl1.ger.corp.intel.com (HELO fedora..) ([10.245.246.73]) by fmviesa007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Mar 2025 14:04:53 -0700 From: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= To: intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org Cc: =?UTF-8?q?Thomas=20Hellstr=C3=B6m?= , himal.prasad.ghimiray@intel.com, apopple@nvidia.com, airlied@gmail.com, Simona Vetter , felix.kuehling@amd.com, Matthew Brost , =?UTF-8?q?Christian=20K=C3=B6nig?= , dakr@kernel.org, "Mrozek, Michal" , Joonas Lahtinen Subject: [RFC PATCH 02/19] drm/xe/svm: Fix a potential bo UAF Date: Wed, 12 Mar 2025 22:03:59 +0100 Message-ID: <20250312210416.3120-3-thomas.hellstrom@linux.intel.com> X-Mailer: git-send-email 2.48.1 In-Reply-To: <20250312210416.3120-1-thomas.hellstrom@linux.intel.com> References: <20250312210416.3120-1-thomas.hellstrom@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-BeenThere: intel-xe@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel Xe graphics driver List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-xe-bounces@lists.freedesktop.org Sender: "Intel-xe" If drm_gpusvm_migrate_to_devmem() succeeds, if a cpu access happens to the range the bo may be freed before xe_bo_unlock(), causing a UAF. Since the reference is transferred, use xe_svm_devmem_release() to release the reference on drm_gpusvm_migrate_to_devmem() failure, and hold a local reference to protect the UAF. Signed-off-by: Thomas Hellström --- drivers/gpu/drm/xe/xe_svm.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/xe/xe_svm.c b/drivers/gpu/drm/xe/xe_svm.c index c305d4c351d7..1a8e17a0005d 100644 --- a/drivers/gpu/drm/xe/xe_svm.c +++ b/drivers/gpu/drm/xe/xe_svm.c @@ -701,11 +701,14 @@ static int xe_svm_alloc_vram(struct xe_vm *vm, struct xe_tile *tile, list_for_each_entry(block, blocks, link) block->private = vr; + xe_bo_get(bo); err = drm_gpusvm_migrate_to_devmem(&vm->svm.gpusvm, &range->base, &bo->devmem_allocation, ctx); - xe_bo_unlock(bo); if (err) - xe_bo_put(bo); /* Creation ref */ + xe_svm_devmem_release(&bo->devmem_allocation); + + xe_bo_unlock(bo); + xe_bo_put(bo); unlock: mmap_read_unlock(mm); -- 2.48.1