From patchwork Mon May 11 04:45:49 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Al Viro X-Patchwork-Id: 219505 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=-9.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH, MAILING_LIST_MULTI, SIGNED_OFF_BY, SPF_HELO_NONE, SPF_PASS, URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable 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 7E133C54E4A for ; Mon, 11 May 2020 04:46:27 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 66FEC20820 for ; Mon, 11 May 2020 04:46:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728722AbgEKEqZ (ORCPT ); Mon, 11 May 2020 00:46:25 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33444 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1728355AbgEKEp6 (ORCPT ); Mon, 11 May 2020 00:45:58 -0400 Received: from ZenIV.linux.org.uk (zeniv.linux.org.uk [IPv6:2002:c35c:fd02::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id E56C2C061A0C; Sun, 10 May 2020 21:45:57 -0700 (PDT) Received: from viro by ZenIV.linux.org.uk with local (Exim 4.92.3 #3 (Red Hat Linux)) id 1jY0KC-005jJ3-7c; Mon, 11 May 2020 04:45:56 +0000 From: Al Viro To: netdev@vger.kernel.org Cc: davem@davemloft.net, viro@zeniv.linux.org.uk, linux-kernel@vger.kernel.org Subject: [PATCH 15/19] atm: separate ATM_GETNAMES handling from the rest of atm_dev_ioctl() Date: Mon, 11 May 2020 05:45:49 +0100 Message-Id: <20200511044553.1365660-15-viro@ZenIV.linux.org.uk> X-Mailer: git-send-email 2.25.4 In-Reply-To: <20200511044553.1365660-1-viro@ZenIV.linux.org.uk> References: <20200511044328.GP23230@ZenIV.linux.org.uk> <20200511044553.1365660-1-viro@ZenIV.linux.org.uk> MIME-Version: 1.0 Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Al Viro atm_dev_ioctl() does copyin in two different ways - one for ATM_GETNAMES, another for everything else. Start with separating the former into a new helper (atm_getnames()). The next step will be to lift the copyin into the callers. Signed-off-by: Al Viro --- net/atm/ioctl.c | 6 +++- net/atm/resources.c | 88 +++++++++++++++++++++++++++-------------------------- net/atm/resources.h | 1 + 3 files changed, 51 insertions(+), 44 deletions(-) diff --git a/net/atm/ioctl.c b/net/atm/ioctl.c index d955b683aa7c..0b4b07740fe4 100644 --- a/net/atm/ioctl.c +++ b/net/atm/ioctl.c @@ -162,7 +162,11 @@ static int do_vcc_ioctl(struct socket *sock, unsigned int cmd, if (error != -ENOIOCTLCMD) goto done; - error = atm_dev_ioctl(cmd, argp, compat); + if (cmd == ATM_GETNAMES) { + error = atm_getnames(argp, compat); + } else { + error = atm_dev_ioctl(cmd, argp, compat); + } done: return error; diff --git a/net/atm/resources.c b/net/atm/resources.c index 889349c6d90d..a2ab75929eec 100644 --- a/net/atm/resources.c +++ b/net/atm/resources.c @@ -193,61 +193,63 @@ static int fetch_stats(struct atm_dev *dev, struct atm_dev_stats __user *arg, return error ? -EFAULT : 0; } -int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat) +int atm_getnames(void __user *arg, int compat) { void __user *buf; - int error, len, number, size = 0; + int error, len, size = 0; struct atm_dev *dev; struct list_head *p; int *tmp_buf, *tmp_p; - int __user *sioc_len; int __user *iobuf_len; - switch (cmd) { - case ATM_GETNAMES: - if (IS_ENABLED(CONFIG_COMPAT) && compat) { + if (IS_ENABLED(CONFIG_COMPAT) && compat) { #ifdef CONFIG_COMPAT - struct compat_atm_iobuf __user *ciobuf = arg; - compat_uptr_t cbuf; - iobuf_len = &ciobuf->length; - if (get_user(cbuf, &ciobuf->buffer)) - return -EFAULT; - buf = compat_ptr(cbuf); + struct compat_atm_iobuf __user *ciobuf = arg; + compat_uptr_t cbuf; + iobuf_len = &ciobuf->length; + if (get_user(cbuf, &ciobuf->buffer)) + return -EFAULT; + buf = compat_ptr(cbuf); #endif - } else { - struct atm_iobuf __user *iobuf = arg; - iobuf_len = &iobuf->length; - if (get_user(buf, &iobuf->buffer)) - return -EFAULT; - } - if (get_user(len, iobuf_len)) + } else { + struct atm_iobuf __user *iobuf = arg; + iobuf_len = &iobuf->length; + if (get_user(buf, &iobuf->buffer)) return -EFAULT; - mutex_lock(&atm_dev_mutex); - list_for_each(p, &atm_devs) - size += sizeof(int); - if (size > len) { - mutex_unlock(&atm_dev_mutex); - return -E2BIG; - } - tmp_buf = kmalloc(size, GFP_ATOMIC); - if (!tmp_buf) { - mutex_unlock(&atm_dev_mutex); - return -ENOMEM; - } - tmp_p = tmp_buf; - list_for_each(p, &atm_devs) { - dev = list_entry(p, struct atm_dev, dev_list); - *tmp_p++ = dev->number; - } + } + if (get_user(len, iobuf_len)) + return -EFAULT; + mutex_lock(&atm_dev_mutex); + list_for_each(p, &atm_devs) + size += sizeof(int); + if (size > len) { mutex_unlock(&atm_dev_mutex); - error = ((copy_to_user(buf, tmp_buf, size)) || - put_user(size, iobuf_len)) - ? -EFAULT : 0; - kfree(tmp_buf); - return error; - default: - break; + return -E2BIG; } + tmp_buf = kmalloc(size, GFP_ATOMIC); + if (!tmp_buf) { + mutex_unlock(&atm_dev_mutex); + return -ENOMEM; + } + tmp_p = tmp_buf; + list_for_each(p, &atm_devs) { + dev = list_entry(p, struct atm_dev, dev_list); + *tmp_p++ = dev->number; + } + mutex_unlock(&atm_dev_mutex); + error = ((copy_to_user(buf, tmp_buf, size)) || + put_user(size, iobuf_len)) + ? -EFAULT : 0; + kfree(tmp_buf); + return error; +} + +int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat) +{ + void __user *buf; + int error, len, number, size = 0; + struct atm_dev *dev; + int __user *sioc_len; if (IS_ENABLED(CONFIG_COMPAT) && compat) { #ifdef CONFIG_COMPAT diff --git a/net/atm/resources.h b/net/atm/resources.h index 048232e4d4c6..18f8e5948ce4 100644 --- a/net/atm/resources.h +++ b/net/atm/resources.h @@ -14,6 +14,7 @@ extern struct list_head atm_devs; extern struct mutex atm_dev_mutex; +int atm_getnames(void __user *arg, int compat); int atm_dev_ioctl(unsigned int cmd, void __user *arg, int compat);