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=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 A43EEC433ED for ; Tue, 27 Apr 2021 12:40:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78BCA613C3 for ; Tue, 27 Apr 2021 12:40:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236039AbhD0Mkn (ORCPT ); Tue, 27 Apr 2021 08:40:43 -0400 Received: from mail.kernel.org ([198.145.29.99]:54886 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235410AbhD0Mkm (ORCPT ); Tue, 27 Apr 2021 08:40:42 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 6A9D3613C2; Tue, 27 Apr 2021 12:39:58 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1619527198; bh=c5N3WbqsojdSsTwqANIzFRqj+y1qdfjxsQVVwX7SktQ=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=A6oPTDnuuxTg+YCpj9Nm7KnWelXw87PIcEo3nOIuK7GSMt2jGL7RyFuMn3ZEfrdDB 0YNRzhZtN/FHQqLfWaPGxjdur9sMcFgV6wZOXfDj+mND5VRHQUzLP9+EIOdts7vhKK hO0c4oRBYDZKS6GfN9rYCVJJuutF61NbnGdDgQRs= Date: Tue, 27 Apr 2021 14:39:56 +0200 From: Greg Kroah-Hartman To: ashish Cc: Joe Perches , Abheek Dhawan , Johannes Weiner , Romain Perier , Waiman Long , Allen Pais , Ivan Safonov , linux-staging@lists.linux.dev, linux-kernel@vger.kernel.org Subject: Re: [PATCH] staging: wlan-ng: silence incorrect type in argument 1 (different address spaces) warning Message-ID: References: <20210420090142.GA4086@ashish-NUC8i5BEH> <20210423152619.GA2469@ashish-NUC8i5BEH> <20210424081529.GA1731@ubuntu> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Apr 27, 2021 at 05:53:30PM +0530, ashish wrote: > On Sat, Apr 24, 2021 at 10:28:27AM +0200, Greg Kroah-Hartman wrote: > > On Sat, Apr 24, 2021 at 01:45:29PM +0530, Ashish Kalra wrote: > > > On Fri, Apr 23, 2021 at 11:11:05PM -0700, Joe Perches wrote: > > > > On Sat, 2021-04-24 at 08:00 +0200, Greg Kroah-Hartman wrote: > > > > > On Fri, Apr 23, 2021 at 08:56:19PM +0530, Ashish Kalra wrote: > > > > > > On Thu, Apr 22, 2021 at 10:43:13AM +0200, Greg Kroah-Hartman wrote: > > > > > > > On Tue, Apr 20, 2021 at 02:31:42PM +0530, Ashish Kalra wrote: > > > > > > > > Upon running sparse, "warning: incorrect type in argument 1 (different address spaces) > > > > > > > > is brought to notice for this file.let's add correct typecast to make it cleaner and > > > > > > > > silence the Sparse warning. > > > > [] > > > > > >  struct p80211ioctl_req { > > > > > >         char name[WLAN_DEVNAMELEN_MAX]; > > > > > > - caddr_t data; > > > > > > + void __user *data; > > > > > > > > > > > > Does this looks ok to you and is there any other check possible if this is ok? > > > > > > > > > > Wait, what is "caddr_t"? Try unwinding that mess first... > > > > > > > > Might not be that simple. > > > > > > > > include/linux/types.h:typedef __kernel_caddr_t caddr_t; > > > > include/uapi/linux/coda.h:typedef void * caddr_t; > > > > include/uapi/asm-generic/posix_types.h:typedef char * __kernel_caddr_t; > > > > > > > > > > > data is part of p80211ioctl_req and is used at two places only inside p80211knetdev_do_ioctl > > > it seems both places it will be used as void __user* only > > > > > > msgbuf = memdup_user(req->data, req->len); > > > > > > if (result == 0) { > > > if (copy_to_user > > > ((void __user *)req->data, msgbuf, req->len)) { > > > result = -EFAULT; > > > } > > > } > > > > > > Will it still be problem if we change it from char * to void *.? > > > > Why do you want to change it to void *? Never use a void * unless it > > has to point to unknown data. That does not seem the case here. > > > > > is there any way to check how caller of this function will be using it? > > > > Look at the code to determine this... > > > > thanks, > > > > greg k-h > Thanks Greg and Joe > I have found that adding __user to data is also fixing this warning, > It should be fine logically to make this change > Please share your opinion and will post v2 for this patch > > --- a/drivers/staging/wlan-ng/p80211ioctl.h > +++ b/drivers/staging/wlan-ng/p80211ioctl.h > @@ -81,7 +81,7 @@ > > struct p80211ioctl_req { > char name[WLAN_DEVNAMELEN_MAX]; > - caddr_t data; > + char __user *data; > u32 magic; > u16 len; > u32 result; > -- > 2.30.2 > > > What do you think, try it and see and if you think it is correct, please submit that change. Don't wait for us... thanks, greg k-h