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=-6.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,UNWANTED_LANGUAGE_BODY,USER_AGENT_GIT 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 6AEE7C47255 for ; Mon, 11 May 2020 11:59:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 4270A20722 for ; Mon, 11 May 2020 11:59:23 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="D0bz4+3n" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729833AbgEKL7W (ORCPT ); Mon, 11 May 2020 07:59:22 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44130 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1729645AbgEKL7V (ORCPT ); Mon, 11 May 2020 07:59:21 -0400 Received: from bombadil.infradead.org (bombadil.infradead.org [IPv6:2607:7c80:54:e::133]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 94DF9C05BD09; Mon, 11 May 2020 04:59:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20170209; h=Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From:Sender :Reply-To:Content-Type:Content-ID:Content-Description; bh=3KzJfnIrMOX10B1smfo4qeEM4MM1jluWGd/OiMkNXVc=; b=D0bz4+3nUcmIBLGugGcmJZOw/i 2ybM76T3XhoNAhvDG2Vu84QStYUI0Fyf4f98sjlPJp0tj57gvNlkAWGPpFbFlubDHXcf5bJy8nxHU JhWRbvQLZivDClQdADk3KG06vfGJrH3O8535gbUD+Cg9zpQ6py5oJ8iSi2of6tNnhwE4JN3yyYJ0A fp4L99A+npTq6vLDe42/fTjH7MC7ncJcsPa7dW/arNKGVtiuN6ohC+zGqIpa+rRePvMBDMg9tTspu yMZPxgS7WtEo4xw78y1JZd9XxehEg70DIjUQuBxSRFwLgmgIxEDLVBeQiU39DoyR5n/n06aItYQ3b ht20r09w==; Received: from [2001:4bb8:180:9d3f:c70:4a89:bc61:2] (helo=localhost) by bombadil.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jY75a-0007TM-Jf; Mon, 11 May 2020 11:59:19 +0000 From: Christoph Hellwig To: "David S. Miller" , Jakub Kicinski Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH 1/3] net: add a CMSG_USER_DATA macro Date: Mon, 11 May 2020 13:59:11 +0200 Message-Id: <20200511115913.1420836-2-hch@lst.de> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20200511115913.1420836-1-hch@lst.de> References: <20200511115913.1420836-1-hch@lst.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a variant of CMSG_DATA that operates on user pointer to avoid sparse warnings about casting to/from user pointers. Also fix up CMSG_DATA to rely on the gcc extension that allows void pointer arithmetics to cut down on the amount of casts. Signed-off-by: Christoph Hellwig --- include/linux/socket.h | 5 ++++- net/core/scm.c | 4 ++-- 2 files changed, 6 insertions(+), 3 deletions(-) diff --git a/include/linux/socket.h b/include/linux/socket.h index 54338fac45cb7..4cc64d611cf49 100644 --- a/include/linux/socket.h +++ b/include/linux/socket.h @@ -94,7 +94,10 @@ struct cmsghdr { #define CMSG_ALIGN(len) ( ((len)+sizeof(long)-1) & ~(sizeof(long)-1) ) -#define CMSG_DATA(cmsg) ((void *)((char *)(cmsg) + sizeof(struct cmsghdr))) +#define CMSG_DATA(cmsg) \ + ((void *)(cmsg) + sizeof(struct cmsghdr)) +#define CMSG_USER_DATA(cmsg) \ + ((void __user *)(cmsg) + sizeof(struct cmsghdr)) #define CMSG_SPACE(len) (sizeof(struct cmsghdr) + CMSG_ALIGN(len)) #define CMSG_LEN(len) (sizeof(struct cmsghdr) + (len)) diff --git a/net/core/scm.c b/net/core/scm.c index dc6fed1f221c4..abfdc85a64c1b 100644 --- a/net/core/scm.c +++ b/net/core/scm.c @@ -236,7 +236,7 @@ int put_cmsg(struct msghdr * msg, int level, int type, int len, void *data) err = -EFAULT; if (copy_to_user(cm, &cmhdr, sizeof cmhdr)) goto out; - if (copy_to_user(CMSG_DATA(cm), data, cmlen - sizeof(struct cmsghdr))) + if (copy_to_user(CMSG_USER_DATA(cm), data, cmlen - sizeof(*cm))) goto out; cmlen = CMSG_SPACE(len); if (msg->msg_controllen < cmlen) @@ -300,7 +300,7 @@ void scm_detach_fds(struct msghdr *msg, struct scm_cookie *scm) if (fdnum < fdmax) fdmax = fdnum; - for (i=0, cmfptr=(__force int __user *)CMSG_DATA(cm); i