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=-3.8 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 EAB5DC4332B for ; Fri, 20 Mar 2020 06:58:03 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C097920773 for ; Fri, 20 Mar 2020 06:58:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584687483; bh=PIsypC08bJWE4+6MHuQaFuvnG+0cWY+CmeuIGkWOgCY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=nZanqcUEIxvDEAEFHfcFR2gWYewvJ80aGxenehd12ryBNGEbNVFD5depbEaVas8rg oJLCGLDk9XhzirV6Rkaem+6l7in+6RhO68gD0MKkf+08sVeSpE5iIztUsj56z4L1UU nSymTS655qIi/biBQ6eYzJjlvgYcm5m7FKA19e2M= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726806AbgCTG6D (ORCPT ); Fri, 20 Mar 2020 02:58:03 -0400 Received: from mail.kernel.org ([198.145.29.99]:58828 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726232AbgCTG6C (ORCPT ); Fri, 20 Mar 2020 02:58:02 -0400 Received: from localhost (83-86-89-107.cable.dynamic.v4.ziggo.nl [83.86.89.107]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 39C7220724; Fri, 20 Mar 2020 06:58:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1584687481; bh=PIsypC08bJWE4+6MHuQaFuvnG+0cWY+CmeuIGkWOgCY=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=HfVVJ8Ed99pmOAmwj9fvwyf8AtF0zak3Pa6CBMSeoWFfBk0ww+GnBdFynv9p6gm8O Fy6/2pfT2jRwoq8pN4MIRj/m2k3sLMyEebmJqP+bRuxZPv5njZTlz5EozE9ZqNGK3T TxJZ4rLXzGdZyLqjHDDtPz0cUacPKSBO+iZegXFY= Date: Fri, 20 Mar 2020 07:57:59 +0100 From: Greg Kroah-Hartman To: Eric Biggers Cc: Jiri Slaby , linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org, syzkaller-bugs@googlegroups.com, Eric Dumazet , Nicolas Pitre Subject: Re: [PATCH v2 1/2] vt: vt_ioctl: fix VT_DISALLOCATE freeing in-use virtual console Message-ID: <20200320065759.GA307955@kroah.com> References: <20200318222704.GC2334@sol.localdomain> <20200318223810.162440-1-ebiggers@kernel.org> <20200318223810.162440-2-ebiggers@kernel.org> <2f762aee-720b-9bec-620f-61129c724de6@suse.com> <20200320051049.GA1315@sol.localdomain> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200320051049.GA1315@sol.localdomain> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Mar 19, 2020 at 10:10:49PM -0700, Eric Biggers wrote: > On Thu, Mar 19, 2020 at 08:36:28AM +0100, Jiri Slaby wrote: > > On 18. 03. 20, 23:38, Eric Biggers wrote: > > > --- a/drivers/tty/vt/vt.c > > > +++ b/drivers/tty/vt/vt.c > > > @@ -1102,6 +1102,9 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */ > > > tty_port_init(&vc->port); > > > INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK); > > > > > > + /* if this wasn't the case, we'd have to implement port->ops.destruct */ > > > + BUILD_BUG_ON(offsetof(struct vc_data, port) != 0); > > > + > > > > This is 3 lines, implementing destruct would be like 4-5 :)? Please > > implement destruct instead. > > > > Otherwise looks good. > > > > Actually implementing destruct would be 12 lines, see below. Remember there is > no tty_port_operations defined yet so we'd have to define it just for destruct. > > Do you still prefer it? > > diff --git a/drivers/tty/vt/vt.c b/drivers/tty/vt/vt.c > index ec34f1f5f3bb5..309a39197be0a 100644 > --- a/drivers/tty/vt/vt.c > +++ b/drivers/tty/vt/vt.c > @@ -1075,6 +1075,17 @@ static void visual_deinit(struct vc_data *vc) > module_put(vc->vc_sw->owner); > } > > +static void vc_port_destruct(struct tty_port *port) > +{ > + struct vc_data *vc = container_of(port, struct vc_data, port); > + > + kfree(vc); > +} > + > +static const struct tty_port_operations vc_port_ops = { > + .destruct = vc_port_destruct, > +}; > + > int vc_allocate(unsigned int currcons) /* return 0 on success */ > { > struct vt_notifier_param param; > @@ -1100,11 +1111,9 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */ > > vc_cons[currcons].d = vc; > tty_port_init(&vc->port); > + vc->port.ops = &vc_port_ops; > INIT_WORK(&vc_cons[currcons].SAK_work, vc_SAK); > > - /* if this wasn't the case, we'd have to implement port->ops.destruct */ > - BUILD_BUG_ON(offsetof(struct vc_data, port) != 0); > - > visual_init(vc, currcons, 1); > > if (!*vc->vc_uni_pagedir_loc) Yes, this is good to have, thanks for doing this. greg k-h