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 B5B81C43458 for ; Tue, 30 Jun 2026 13:45:56 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 29C2410EA15; Tue, 30 Jun 2026 13:45:56 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.b="Jt2Ja/qD"; dkim-atps=neutral Received: from sea.source.kernel.org (sea.source.kernel.org [172.234.252.31]) by gabe.freedesktop.org (Postfix) with ESMTPS id B9CDB10EA15 for ; Tue, 30 Jun 2026 13:45:54 +0000 (UTC) Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) by sea.source.kernel.org (Postfix) with ESMTP id 5A45740100; Tue, 30 Jun 2026 13:45:54 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 140721F000E9; Tue, 30 Jun 2026 13:45:54 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782827154; bh=jLGVe1tT+1Ii95ToR3br/YDPL8BQF6jZu7Qv+ibrAY0=; h=From:Subject:Reply-To:To:Cc:In-Reply-To:References:Date; b=Jt2Ja/qDZh+Fy/Qp8A8UEnPiaqXDVvjYOprX7d/C5iOIrIzlW7GS4XRseTG8lt/VY o4OZU1ASnn5SnyVU8hF6F2DoR05AZlUv6p3IBAedn7DBj0v1T+F5wMQ7KY5sKTUvrK gwSfBPceGd4yC6+eY/e6UokOtk1WOhAahbqLBTJbSPZjRiQ0OCY1+wXrNE9W0RLX/b j+p1JSXo0NHAhnVIwfcwy0MMbiMAzqssKO40+UO0m7YDgHLnwF2aBpUAwavYR4nR1h 1fdmbr4dZCu8kC8+rrfmYq/m9ar1/p6FMSXpZgESovXUpSGyWyHktqIvU38G9J7woZ WSAX5sLjfza7w== From: sashiko-bot@kernel.org Subject: Re: [PATCH v2] drm/vmwgfx: Fix NULL vs error pointer bug in vmw_prime_import_sg_table() To: "Dan Carpenter" Cc: dri-devel@lists.freedesktop.org In-Reply-To: References: Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable Date: Tue, 30 Jun 2026 13:45:53 +0000 Message-Id: <20260630134554.140721F000E9@smtp.kernel.org> X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: sashiko-reviews@lists.linux.dev Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" Thank you for your contribution! Sashiko AI review found 1 potential issue(= s) to consider: Pre-existing issues: - [High] Imported DMA buffers and their scatterlist mappings are leaked bec= ause vmw_gem_object_free() does not call drm_prime_gem_destroy(). -- commit 122b763cb3d6da8120f8ce7568a560873e4c1325 Author: Dan Carpenter drm/vmwgfx: Fix NULL vs error pointer bug in vmw_prime_import_sg_table() The vmw_prime_import_sg_table() function is expected to return error pointers on error and not NULL. Otherwise it leads to a NULL dereference in the caller drm_gem_prime_import_dev(). Propagate the error code from vmw_bo_create(). Fixes: b32233acceff ("drm/vmwgfx: Fix prime import/export") Signed-off-by: Dan Carpenter > diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_gem.c b/drivers/gpu/drm/vmwgfx= /vmwgfx_gem.c > index 39f8c46550c27..93a92ae625f8e 100644 > --- a/drivers/gpu/drm/vmwgfx/vmwgfx_gem.c > +++ b/drivers/gpu/drm/vmwgfx/vmwgfx_gem.c [ ... ] > @@ -201,8 +201,10 @@ struct drm_gem_object *vmw_prime_import_sg_table(str= uct drm_device *dev, > dma_resv_lock(params.resv, NULL); > =20 > ret =3D vmw_bo_create(dev_priv, ¶ms, &vbo); > - if (ret !=3D 0) > + if (ret !=3D 0) { > + gem =3D ERR_PTR(ret); > goto out_no_bo; > + } > =20 > vbo->tbo.base.funcs =3D &vmw_gem_object_funcs; [Severity: High] This is a pre-existing issue, but while reviewing the dmabuf import lifecyc= le, I noticed a potential memory leak in the GEM object free hook. The DRM core contract requires drivers using the generic dmabuf import help= er to call drm_prime_gem_destroy() to unmap and free the dmabuf attachment when the object is freed. Looking at vmw_gem_object_free() in the same file: static void vmw_gem_object_free(struct drm_gem_object *gobj) { struct ttm_buffer_object *bo =3D drm_gem_ttm_of_gem(gobj); if (bo) ttm_bo_fini(bo); } Because this completely omits the drm_prime_gem_destroy() call, does this l= eak the dma_buf_attachment and sg_table? Could an untrusted userspace application trigger a denial-of-service by repeatedly importing and closing dmabufs, permanently pinning the exported buffers in memory? --=20 Sashiko AI review =C2=B7 https://sashiko.dev/#/patchset/akPFZ-e9usvsYgf_@st= anley.mountain?part=3D1