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 X-Spam-Level: X-Spam-Status: No, score=-8.4 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id BCA90C2D0EC for ; Sun, 12 Apr 2020 20:31:36 +0000 (UTC) Received: from vger.kernel.org (unknown [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 895BD206C3 for ; Sun, 12 Apr 2020 20:31:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="IYa0DR4v" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 895BD206C3 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728101AbgDLUbe (ORCPT ); Sun, 12 Apr 2020 16:31:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.18]:36072 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727315AbgDLUbe (ORCPT ); Sun, 12 Apr 2020 16:31:34 -0400 Received: from us-smtp-delivery-1.mimecast.com (us-smtp-1.mimecast.com [207.211.31.81]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 62DE2C0A3BF0 for ; Sun, 12 Apr 2020 13:31:34 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1586723492; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type; bh=pdGxSItAg1hNt0eqCWfo1nI029akRqxf1Spx/SODDE0=; b=IYa0DR4vZExMDqHF38+mPoE5RZAWX2nZsH80KY0CJcLmOnBTGa0sxl0eEHKihUwENb2fdZ WVaNJS8ZN6sjbLJJGLeLKpXpjDX/3pWyUqj0aOXyR5+y5+YG49ivcZh2on0dEV89a4zgqI 90laz446+EYhP4glxT563+1S8qALPHg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-489-yQDXnCojP_CJE4SAeSV1FA-1; Sun, 12 Apr 2020 16:31:28 -0400 X-MC-Unique: yQDXnCojP_CJE4SAeSV1FA-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id AF766801E53; Sun, 12 Apr 2020 20:31:26 +0000 (UTC) Received: from asgard.redhat.com (unknown [10.36.110.6]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B006610013D9; Sun, 12 Apr 2020 20:31:24 +0000 (UTC) Date: Sun, 12 Apr 2020 22:31:23 +0200 From: Eugene Syromiatnikov To: linux-kernel@vger.kernel.org, Christian Brauner Cc: Andrew Morton , Ingo Molnar , Tejun Heo , Peter Zijlstra , "Dmitry V. Levin" Subject: [PATCH] clone3: add a check for the user struct size if CLONE_INTO_CGROUP is set Message-ID: <20200412203123.GA5869@asgard.redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.22 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Passing CLONE_INTO_CGROUP with an under-sized structure (that doesn't properly contain cgroup field) seems like garbage input, especially considering the fact that fd 0 is a valid descriptor. Signed-off-by: Eugene Syromiatnikov --- kernel/fork.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/kernel/fork.c b/kernel/fork.c index 11bcc7e..8c700f8 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -2639,7 +2639,8 @@ noinline static int copy_clone_args_from_user(struct kernel_clone_args *kargs, !valid_signal(args.exit_signal))) return -EINVAL; - if ((args.flags & CLONE_INTO_CGROUP) && args.cgroup > INT_MAX) + if ((args.flags & CLONE_INTO_CGROUP) && + (args.cgroup > INT_MAX || usize < CLONE_ARGS_SIZE_VER2)) return -EINVAL; *kargs = (struct kernel_clone_args){ -- 2.1.4