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 4EBECD16818 for ; Fri, 9 Jan 2026 12:02:34 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id A455110E8A9; Fri, 9 Jan 2026 12:02:33 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=collabora.com header.i=@collabora.com header.b="VrFMd+0g"; dkim-atps=neutral Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) by gabe.freedesktop.org (Postfix) with ESMTPS id 31B1A10E8A9 for ; Fri, 9 Jan 2026 12:02:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1767960150; bh=wj0vveR25kaX8yWy/lFG+v+P+7tYmaklUTSQKJWmb3c=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=VrFMd+0gHV6qr0oxB+XhSMespbpFK6/MK3HoO5nr04+PnIHYVb2xsa8ePDInLlPq4 xVOzC/k7RGipcJSP/r9SNAfBQ21kc8tNZBsK9r+cEzMK54CzAL0OJozm2DAPt9mpvA SMgbjiuUvjGQWg29AbB4BE6mqQm0iUFa2PPlBKGgQBzafOpsDkRDDvoAJToc/WErmJ /GPpYc1nuZtM6QPgOt1q1BbLm4cC7MEr51yOeDxphbpowN1x5N3HvH9cXhMF0Aca1O 0a6RRrFayVeWtgMvBasM88bFTlkUGMU2TFnFEkfeKT+LieOQNvVYToUzc2DAhzf+w7 BnUdq26lwpgKw== Received: from fedora (unknown [IPv6:2a01:e0a:2c:6930:d919:a6e:5ea1:8a9f]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange ECDHE (prime256v1) server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: bbrezillon) by bali.collaboradmins.com (Postfix) with ESMTPSA id 5060917E1380; Fri, 9 Jan 2026 13:02:30 +0100 (CET) Date: Fri, 9 Jan 2026 13:02:24 +0100 From: Boris Brezillon To: dri-devel@lists.freedesktop.org, David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann Cc: kernel@collabora.com, =?UTF-8?B?TG/Dr2M=?= Molinari Subject: Re: [PATCH] drm/gem: Fix a GEM leak in drm_gem_get_unmapped_area() Message-ID: <20260109130224.741d463f@fedora> In-Reply-To: <20260106164935.409765-1-boris.brezillon@collabora.com> References: <20260106164935.409765-1-boris.brezillon@collabora.com> Organization: Collabora X-Mailer: Claws Mail 4.3.1 (GTK 3.24.51; x86_64-redhat-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable 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: , Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Tue, 6 Jan 2026 17:49:35 +0100 Boris Brezillon wrote: > drm_gem_object_lookup_at_offset() can return a valid object with > filp or filp->f_op->get_unmapped_area set to NULL. Make sure we still > release the ref we acquired on such objects. >=20 > Cc: Lo=C3=AFc Molinari > Fixes: 99bda20d6d4c ("drm/gem: Introduce drm_gem_get_unmapped_area() fop") > Signed-off-by: Boris Brezillon Queued to drm-misc-next. > --- > drivers/gpu/drm/drm_gem.c | 10 ++++++---- > 1 file changed, 6 insertions(+), 4 deletions(-) >=20 > diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c > index 36c8af123877..f7cbf6e8d1e0 100644 > --- a/drivers/gpu/drm/drm_gem.c > +++ b/drivers/gpu/drm/drm_gem.c > @@ -1298,11 +1298,13 @@ unsigned long drm_gem_get_unmapped_area(struct fi= le *filp, unsigned long uaddr, > unsigned long ret; > =20 > obj =3D drm_gem_object_lookup_at_offset(filp, pgoff, len >> PAGE_SHIFT); > - if (IS_ERR(obj) || !obj->filp || !obj->filp->f_op->get_unmapped_area) > - return mm_get_unmapped_area(filp, uaddr, len, 0, flags); > + if (IS_ERR(obj)) > + obj =3D NULL; > =20 > - ret =3D obj->filp->f_op->get_unmapped_area(obj->filp, uaddr, len, 0, > - flags); > + if (!obj || !obj->filp || !obj->filp->f_op->get_unmapped_area) > + ret =3D mm_get_unmapped_area(filp, uaddr, len, 0, flags); > + else > + ret =3D obj->filp->f_op->get_unmapped_area(obj->filp, uaddr, len, 0, f= lags); > =20 > drm_gem_object_put(obj); > =20