From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from greygoose-centos7.csh.rit.edu (greygoose-centos7.csh.rit.edu [129.21.49.170]) (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 5079F1957FC; Thu, 2 Oct 2025 14:34:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=129.21.49.170 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759415652; cv=none; b=hxeNOyn7UyTbTxrIDXSn36s/jxE7vQEbdoOvUZEYAd+niC0QS4gifIjPR7dutbTQ2on/zPH93VyNkt8ZFb3HfnYCj/zImdU+7zk6LNXp7woWq4bkc8yv1/grLvj4hYZOAbxM2ndBgNh7+8WhSWaBmB1LVfKMhJlT/QD80ItK8s8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759415652; c=relaxed/simple; bh=0+hBZlIHCcxmL043sNFgXlbynkcBYvJ/x1ZRv1zYs9Y=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=kFPs0XoTM8GOn+zZMXBRvmVRjenue1Nyc9VzPkolUUEsreoE944yaERAeukpK+ku+Tt3X+HdWzlurxinMqNs0y8hI+IoR2TmO6cdtg2+lKdMpHlFU+Ho7gOczGMfC+932g5KhQLUxMMXMWRkfjq+/JS9p9MiQBo2oRzRBp3cDtg= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=csh.rit.edu; spf=pass smtp.mailfrom=csh.rit.edu; dkim=pass (1024-bit key) header.d=csh.rit.edu header.i=@csh.rit.edu header.b=uyl5NmVU; arc=none smtp.client-ip=129.21.49.170 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=csh.rit.edu Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=csh.rit.edu Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=csh.rit.edu header.i=@csh.rit.edu header.b="uyl5NmVU" Received: from localhost (localhost [127.0.0.1]) by greygoose-centos7.csh.rit.edu (Postfix) with ESMTP id 4300D40EA0BD; Thu, 2 Oct 2025 10:34:09 -0400 (EDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=csh.rit.edu; h= in-reply-to:content-disposition:content-type:content-type :mime-version:references:message-id:subject:subject:from:from :date:date:received:received; s=mail; t=1759415642; x= 1761230043; bh=0+hBZlIHCcxmL043sNFgXlbynkcBYvJ/x1ZRv1zYs9Y=; b=u yl5NmVUyIWFGktDPw5cAzWvHaOSCFRaq67NZGA0UMT1Lv9LhpwEdHeyzthklGKbY MHCgbzczgX0p14POR8IIO2hyJgs9YEIy5fsgLLB4u18NA2ArKEO9aGwPSZKk4kEc kPJqnsd3W5RUvGqZVMkWgz/FrgOdbS3oT2keiEkIFo= X-Virus-Scanned: amavisd-new at csh.rit.edu Received: from greygoose-centos7.csh.rit.edu ([127.0.0.1]) by localhost (mail.csh.rit.edu [127.0.0.1]) (amavisd-new, port 10026) with ESMTP id hvOBuQ72scso; Thu, 2 Oct 2025 10:34:02 -0400 (EDT) Received: from ada.csh.rit.edu (ada.csh.rit.edu [129.21.49.156]) by greygoose-centos7.csh.rit.edu (Postfix) with ESMTPS id CA82B45735E9; Thu, 2 Oct 2025 10:34:02 -0400 (EDT) Date: Thu, 2 Oct 2025 10:34:01 -0400 From: Mary Strodl To: Tzung-Bi Shih Cc: Linus Walleij , linux-kernel@vger.kernel.org, brgl@bgdev.pl, linux-gpio@vger.kernel.org, "Paul E. McKenney" Subject: Re: [PATCH v2 1/3] gpio: mpsse: use rcu to ensure worker is torn down Message-ID: References: <20250923133304.273529-1-mstrodl@csh.rit.edu> <20250923133304.273529-2-mstrodl@csh.rit.edu> Precedence: bulk X-Mailing-List: linux-gpio@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Hello! On Thu, Oct 02, 2025 at 10:03:33PM +0800, Tzung-Bi Shih wrote: > To use revocable API, we need to identify what resources should protect. It > seems there are some UAF possibilities in gpio_mpsse_poll() after unplugging > the device. Yeah, that's what the cancel_work_sync is supposed to protect. This case is a little weird because the task itself is what could get destroyed on unplug, but it could be cool to have some guarantees around accessing `priv` and other resources in the worker? I'm open to suggestions if you have ideas. Thanks!