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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15061C7EE24 for ; Tue, 6 Jun 2023 03:29:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231268AbjFFD3A (ORCPT ); Mon, 5 Jun 2023 23:29:00 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42702 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230499AbjFFD3A (ORCPT ); Mon, 5 Jun 2023 23:29:00 -0400 Received: from mail.hallyn.com (mail.hallyn.com [178.63.66.53]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1708711B; Mon, 5 Jun 2023 20:28:46 -0700 (PDT) Received: by mail.hallyn.com (Postfix, from userid 1001) id C18AD1D20; Mon, 5 Jun 2023 22:28:44 -0500 (CDT) Date: Mon, 5 Jun 2023 22:28:44 -0500 From: "Serge E. Hallyn" To: "GONG, Ruiqi" Cc: Serge Hallyn , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Wang Weiyang , Xiu Jianfeng , gongruiqi1@huawei.com Subject: Re: [PATCH] capability: erase checker warnings about struct __user_cap_data_struct Message-ID: <20230606032844.GA628899@mail.hallyn.com> References: <20230602054527.290696-1-gongruiqi@huaweicloud.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230602054527.290696-1-gongruiqi@huaweicloud.com> Precedence: bulk List-ID: On Fri, Jun 02, 2023 at 01:45:27PM +0800, GONG, Ruiqi wrote: > Currently Sparse warns the following when compiling kernel/capability.c: > > kernel/capability.c:191:35: warning: incorrect type in argument 2 (different address spaces) > kernel/capability.c:191:35: expected void const *from > kernel/capability.c:191:35: got struct __user_cap_data_struct [noderef] __user * > kernel/capability.c:168:14: warning: dereference of noderef expression > ...... (multiple noderef warnings on different locations) > kernel/capability.c:244:29: warning: incorrect type in argument 1 (different address spaces) > kernel/capability.c:244:29: expected void *to > kernel/capability.c:244:29: got struct __user_cap_data_struct [noderef] __user ( * )[2] > kernel/capability.c:247:42: warning: dereference of noderef expression > ...... (multiple noderef warnings on different locations) > > It seems that defining `struct __user_cap_data_struct` together with > `cap_user_data_t` make Sparse believe that the struct is `noderef` as > well. Separate their definitions to clarify their respective attributes. > > Signed-off-by: GONG, Ruiqi Seems ok. There's still so much noise in the make C=2 output even just for kernel/capability.c that I'm not sure it's worth it, but no objection. Acked-by: Serge Hallyn > --- > include/uapi/linux/capability.h | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/include/uapi/linux/capability.h b/include/uapi/linux/capability.h > index 3d61a0ae055d..5bb906098697 100644 > --- a/include/uapi/linux/capability.h > +++ b/include/uapi/linux/capability.h > @@ -41,11 +41,12 @@ typedef struct __user_cap_header_struct { > int pid; > } __user *cap_user_header_t; > > -typedef struct __user_cap_data_struct { > +struct __user_cap_data_struct { > __u32 effective; > __u32 permitted; > __u32 inheritable; > -} __user *cap_user_data_t; > +}; > +typedef struct __user_cap_data_struct __user *cap_user_data_t; > > > #define VFS_CAP_REVISION_MASK 0xFF000000 > -- > 2.25.1