From nobody Sun Feb 8 17:03:49 2026 Received: from sender4-pp-f112.zoho.com (sender4-pp-f112.zoho.com [136.143.188.112]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BD469143748; Tue, 3 Sep 2024 14:51:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=pass smtp.client-ip=136.143.188.112 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725375081; cv=pass; b=QJ39XbYrJ17O0uOTuCOp/CZxGyURw43GRTUO+SaVQPdIfHczpsv1gSsB/bI7hwMOhkSxzZpx5KcmBidyxNDZjYSV9p1YFGxhcg1h1VRv5aAsNwSV36j3P3PtbTuzOl8xqg4e8+X3gXBa+/83OYqZC2ZlwVp2burR+rn+o1xCEy4= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1725375081; c=relaxed/simple; bh=GURumbuGbZwNDQLNlryk1NuoiF2/LxgRiaV2AXJTKfI=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=qwv/GrN4KFFGn30xww6ucWzVnvb7ecT8TfgdvpaAc5IbRKOx+XEYzFO98/IY1AnkMWfRXy8eJf/UL7LH6LwI9B9KKoZ1WYFIwMta0F4ro654G6pe930Kx2agj8aWYLgp082HGcBLNJGesrvU7Ee42D/nu1uWO3JVwHQju+4E/Ws= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (1024-bit key) header.d=collabora.com header.i=mary.guillemard@collabora.com header.b=XDwDpt5Q; arc=pass smtp.client-ip=136.143.188.112 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=collabora.com header.i=mary.guillemard@collabora.com header.b="XDwDpt5Q" ARC-Seal: i=1; a=rsa-sha256; t=1725375061; cv=none; d=zohomail.com; s=zohoarc; b=FFrPtUkgOiHxCnw5NIFs4L068NZikJBaUfWdpeXS5p7z+BA1SJXDM9QtWHcXygywdrvTY9fG0+ZNe+jf2kDUtBIIDjVkyKSwQ2s4ks66GwcZt3ya/I53cL0B7Ot77Dvj/eGDudstvZeePB7/IY3/7R6U+jJu2ADWljIZfyELEEQ= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zohomail.com; s=zohoarc; t=1725375061; h=Content-Transfer-Encoding:Cc:Cc:Date:Date:From:From:MIME-Version:Message-ID:Subject:Subject:To:To:Message-Id:Reply-To; bh=JoZyTngQaWUmJroKbr6Fpr/n3m9/mAYytfSe+YwDYgo=; b=fj6HZLJetex5KjzqzYK4p9o3lgE3f5iCQZOoOAPGkXdg3X345CHOGdX050xdRg5FR9axIZkOBP0L55rBboAe650V30odLGleMC2OcqQS9UvRS3MZZXiG8D78ST8PQOM2ivTFXe3Be7k0b/EtnS5vgwsUZ8JVtChaE23rvhx5OqA= ARC-Authentication-Results: i=1; mx.zohomail.com; dkim=pass header.i=collabora.com; spf=pass smtp.mailfrom=mary.guillemard@collabora.com; dmarc=pass header.from= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; t=1725375061; s=zohomail; d=collabora.com; i=mary.guillemard@collabora.com; h=From:From:To:To:Cc:Cc:Subject:Subject:Date:Date:Message-ID:MIME-Version:Content-Transfer-Encoding:Message-Id:Reply-To; bh=JoZyTngQaWUmJroKbr6Fpr/n3m9/mAYytfSe+YwDYgo=; b=XDwDpt5Qoth2HKrs8RlmZKcgqljZh/a9XFjXM+n8rk/3jI1Atzxf0tlCVwwQovqf XIQVUVYzXBxA+NalBXoIEDeLEdubbGzjATQ2Qoz+A2n/sVeaVtRxLO0AS9pgViOvvam oxgAq+gyQmtvH42EgZvlfbS8INZDM+l7KChfJIoI= Received: by mx.zohomail.com with SMTPS id 1725375058634587.9557627661392; Tue, 3 Sep 2024 07:50:58 -0700 (PDT) From: Mary Guillemard To: linux-kernel@vger.kernel.org Cc: kernel@collabora.com, Mary Guillemard , stable@vger.kernel.org, Boris Brezillon , Steven Price , Liviu Dudau , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , Heiko Stuebner , dri-devel@lists.freedesktop.org Subject: [PATCH] drm/panthor: Restrict high priorities on group_create Date: Tue, 3 Sep 2024 16:49:55 +0200 Message-ID: <20240903144955.144278-2-mary.guillemard@collabora.com> X-Mailer: git-send-email 2.46.0 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-ZohoMailClient: External Content-Type: text/plain; charset="utf-8" We were allowing any users to create a high priority group without any permission checks. As a result, this was allowing possible denial of service. We now only allow the DRM master or users with the CAP_SYS_NICE capability to set higher priorities than PANTHOR_GROUP_PRIORITY_MEDIUM. As the sole user of that uAPI lives in Mesa and hardcode a value of MEDIUM [1], this should be safe to do. Additionally, as those checks are performed at the ioctl level, panthor_group_create now only check for priority level validity. [1]https://gitlab.freedesktop.org/mesa/mesa/-/blob/f390835074bdf162a63deb03= 11d1a6de527f9f89/src/gallium/drivers/panfrost/pan_csf.c#L1038 Signed-off-by: Mary Guillemard Fixes: de8548813824 ("drm/panthor: Add the scheduler logical block") Cc: stable@vger.kernel.org Reviewed-by: Boris Brezillon --- drivers/gpu/drm/panthor/panthor_drv.c | 23 +++++++++++++++++++++++ drivers/gpu/drm/panthor/panthor_sched.c | 2 +- include/uapi/drm/panthor_drm.h | 6 +++++- 3 files changed, 29 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/panthor/panthor_drv.c b/drivers/gpu/drm/pantho= r/panthor_drv.c index b5e7b919f241..34182f67136c 100644 --- a/drivers/gpu/drm/panthor/panthor_drv.c +++ b/drivers/gpu/drm/panthor/panthor_drv.c @@ -10,6 +10,7 @@ #include #include =20 +#include #include #include #include @@ -996,6 +997,24 @@ static int panthor_ioctl_group_destroy(struct drm_devi= ce *ddev, void *data, return panthor_group_destroy(pfile, args->group_handle); } =20 +static int group_priority_permit(struct drm_file *file, + u8 priority) +{ + /* Ensure that priority is valid */ + if (priority > PANTHOR_GROUP_PRIORITY_HIGH) + return -EINVAL; + + /* Medium priority and below are always allowed */ + if (priority <=3D PANTHOR_GROUP_PRIORITY_MEDIUM) + return 0; + + /* Higher priorities require CAP_SYS_NICE or DRM_MASTER */ + if (capable(CAP_SYS_NICE) || drm_is_current_master(file)) + return 0; + + return -EACCES; +} + static int panthor_ioctl_group_create(struct drm_device *ddev, void *data, struct drm_file *file) { @@ -1011,6 +1030,10 @@ static int panthor_ioctl_group_create(struct drm_dev= ice *ddev, void *data, if (ret) return ret; =20 + ret =3D group_priority_permit(file, args->priority); + if (ret) + return ret; + ret =3D panthor_group_create(pfile, args, queue_args); if (ret >=3D 0) { args->group_handle =3D ret; diff --git a/drivers/gpu/drm/panthor/panthor_sched.c b/drivers/gpu/drm/pant= hor/panthor_sched.c index c426a392b081..91a31b70c037 100644 --- a/drivers/gpu/drm/panthor/panthor_sched.c +++ b/drivers/gpu/drm/panthor/panthor_sched.c @@ -3092,7 +3092,7 @@ int panthor_group_create(struct panthor_file *pfile, if (group_args->pad) return -EINVAL; =20 - if (group_args->priority > PANTHOR_CSG_PRIORITY_HIGH) + if (group_args->priority >=3D PANTHOR_CSG_PRIORITY_COUNT) return -EINVAL; =20 if ((group_args->compute_core_mask & ~ptdev->gpu_info.shader_present) || diff --git a/include/uapi/drm/panthor_drm.h b/include/uapi/drm/panthor_drm.h index 926b1deb1116..e23a7f9b0eac 100644 --- a/include/uapi/drm/panthor_drm.h +++ b/include/uapi/drm/panthor_drm.h @@ -692,7 +692,11 @@ enum drm_panthor_group_priority { /** @PANTHOR_GROUP_PRIORITY_MEDIUM: Medium priority group. */ PANTHOR_GROUP_PRIORITY_MEDIUM, =20 - /** @PANTHOR_GROUP_PRIORITY_HIGH: High priority group. */ + /** + * @PANTHOR_GROUP_PRIORITY_HIGH: High priority group. + * + * Requires CAP_SYS_NICE or DRM_MASTER. + */ PANTHOR_GROUP_PRIORITY_HIGH, }; =20 base-commit: a15710027afb40c7c1e352902fa5b8c949f021de --=20 2.46.0